repos/simple16: src/cpu.c annotate

annotate src/cpu.c @ 0:7e44f7d5810b

Initial commit. CPU working well enough for simple hello world program.

author	Michael Pavone <pavone@retrodev.com>
date	Tue, 22 Mar 2016 22:44:02 -0700
parents
children	6204c81e2933

rev	line source
0 7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	1 #include <stdint.h>
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	2 #include <stdlib.h>
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	3 #include <string.h>
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	4 #include <stdio.h>
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	5 #include "cpu.h"
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	6
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	7 enum {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	8 EXCEPTION_INTERRUPT_0,
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	9 EXCEPTION_INTERRUPT_1,
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	10 EXCEPTION_UNALIGNED_READ,
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	11 EXCEPTION_INVALID_INSTRUCTION
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	12 };
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	13
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	14 enum {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	15 STATE_NEED_FETCH,
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	16 STATE_NORMAL,
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	17 STATE_EXCEPTION_START
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	18 };
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	19
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	20 #define STATUS_INT0_ENABLE 1
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	21 #define STATUS_INT1_ENABLE 2
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	22 #define FLAG_Z 4
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	23 #define FLAG_C 8
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	24 #define FLAG_N 16
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	25
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	26 #define REG_PC 14
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	27 #define REG_SR 15
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	28
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	29 cpu* alloc_cpu(uint32_t clock_divider, uint32_t num_regions, memory_region *regions)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	30 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	31 size_t alloc_size = sizeof(cpu) + sizeof(memory_region) * num_regions;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	32 cpu *context = malloc(alloc_size);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	33 memset(context, 0, alloc_size);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	34 context->clock_inc = clock_divider;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	35 context->num_mem_regions = num_regions;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	36 memcpy(context->mem_regions, regions, num_regions*sizeof(memory_region));
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	37
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	38 return context;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	39 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	40
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	41 uint16_t cpu_read_16(cpu *context, uint16_t address)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	42 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	43 context->cycles += context->clock_inc;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	44 if (address & 1) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	45 context->exception = EXCEPTION_UNALIGNED_READ;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	46 context->state = STATE_EXCEPTION_START;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	47 return 0xFFFF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	48 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	49 memory_region *cur = context->mem_regions;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	50 for (memory_region *end = cur + context->num_mem_regions; cur < end; cur++)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	51 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	52 if (address >= cur->start && address <= cur->end && (cur->flags & MEM_READ)) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	53 return cur->base[address - cur->start] << 8 \| cur->base[address - cur->start + 1];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	54 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	55 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	56 return 0xFFFF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	57 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	58
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	59 uint8_t cpu_read_8(cpu *context, uint16_t address)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	60 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	61 context->cycles += context->clock_inc;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	62 memory_region *cur = context->mem_regions;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	63 for (memory_region *end = cur + context->num_mem_regions; cur < end; cur++)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	64 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	65 if (address >= cur->start && address <= cur->end && (cur->flags & MEM_READ)) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	66 return cur->base[address - cur->start];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	67 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	68 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	69 return 0xFF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	70 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	71
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	72 void cpu_write_16(cpu *context, uint16_t address, uint16_t value)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	73 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	74 context->cycles += context->clock_inc;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	75 if (address & 1) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	76 context->exception = EXCEPTION_UNALIGNED_READ;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	77 context->state = STATE_EXCEPTION_START;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	78 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	79 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	80 memory_region *cur = context->mem_regions;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	81 for (memory_region *end = cur + context->num_mem_regions; cur < end; cur++)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	82 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	83 if (address >= cur->start && address <= cur->end && (cur->flags & MEM_WRITE)) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	84 cur->base[address - cur->start] = value >> 8;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	85 cur->base[address - cur->start + 1] = value;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	86 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	87 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	88 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	89 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	90
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	91 void cpu_write_8(cpu *context, uint16_t address, uint8_t value)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	92 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	93 context->cycles += context->clock_inc;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	94 memory_region *cur = context->mem_regions;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	95 for (memory_region *end = cur + context->num_mem_regions; cur < end; cur++)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	96 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	97 if (address >= cur->start && address <= cur->end && (cur->flags & MEM_WRITE)) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	98 cur->base[address - cur->start] = value;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	99 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	100 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	101 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	102 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	103
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	104 uint16_t cpu_read_port(cpu *context, uint8_t port)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	105 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	106 port &= 0xF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	107 if (context->port_handlers[port].read) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	108 return context->port_handlers[port].read(context, port);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	109 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	110 return 0xFFFF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	111 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	112
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	113 void cpu_write_port(cpu *context, uint8_t port, uint16_t value)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	114 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	115 port &= 0xF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	116 if (context->port_handlers[port].write) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	117 context->port_handlers[port].write(context, port, value);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	118 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	119 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	120
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	121 void fetch_instruction(cpu *context)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	122 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	123 context->prefetch = cpu_read_16(context, context->regs[REG_PC]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	124 context->regs[REG_PC] += 2;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	125 context->state = STATE_NORMAL;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	126 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	127
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	128 void vector_fetch(cpu *context)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	129 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	130 context->exception_pc = context->regs[REG_PC] - 2;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	131 context->exception_sr = context->regs[REG_SR];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	132 context->regs[REG_SR] &= ~(STATUS_INT0_ENABLE \| STATUS_INT1_ENABLE);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	133 context->regs[REG_PC] = cpu_read_16(context, context->vector_base + context->exception);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	134 context->state = STATE_NEED_FETCH;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	135 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	136
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	137 uint16_t sign_extend(uint16_t val)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	138 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	139 if (val & 0x80) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	140 return val \| 0xFF00;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	141 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	142 return val;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	143 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	144
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	145 void update_flags_arith(cpu *context, uint32_t result)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	146 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	147 context->regs[REG_SR] &= ~(FLAG_N\|FLAG_C\|FLAG_Z);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	148 if (!(result & 0xFFFF)) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	149 context->regs[REG_SR] \|= FLAG_Z;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	150 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	151 if (result &= 0x8000) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	152 context->regs[REG_SR] \|= FLAG_N;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	153 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	154 if (result &= 0x10000) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	155 context->regs[REG_SR] \|= FLAG_C;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	156 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	157 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	158
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	159 void update_flags_bitwise(cpu *context, uint32_t result)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	160 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	161 context->regs[REG_SR] &= ~(FLAG_N\|FLAG_Z);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	162 if (!(result & 0xFFFF)) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	163 context->regs[REG_SR] \|= FLAG_Z;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	164 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	165 if (result &= 0x8000) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	166 context->regs[REG_SR] \|= FLAG_N;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	167 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	168 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	169
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	170 void run_bcc(cpu *context, uint8_t condition, uint8_t a, uint8_t b)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	171 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	172
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	173 uint8_t doit = 0;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	174 switch (condition)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	175 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	176 case COND_ALWAYS:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	177 doit = 1;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	178 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	179 case COND_NEVER:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	180 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	181 case COND_ZERO:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	182 doit = context->regs[REG_SR] & FLAG_Z;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	183 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	184 case COND_NZERO:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	185 doit = !(context->regs[REG_SR] & FLAG_Z);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	186 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	187 case COND_NEG:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	188 doit = context->regs[REG_SR] & FLAG_N;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	189 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	190 case COND_POS:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	191 doit = !(context->regs[REG_SR] & FLAG_N);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	192 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	193 case COND_CARRY:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	194 doit = context->regs[REG_SR] & FLAG_C;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	195 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	196 case COND_NCARRY:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	197 doit = context->regs[REG_SR] & FLAG_C;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	198 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	199 case COND_GREATER:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	200 //not zero and not carry
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	201 doit = !(context->regs[REG_SR] & FLAG_Z) \|\| !(context->regs[REG_SR] & FLAG_C);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	202 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	203 case COND_LEQ:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	204 //zero or carry
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	205 doit = (context->regs[REG_SR] & FLAG_Z) \|\| (context->regs[REG_SR] & FLAG_C);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	206 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	207 default:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	208 context->exception = EXCEPTION_INVALID_INSTRUCTION;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	209 context->state = STATE_EXCEPTION_START;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	210 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	211 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	212
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	213 if (doit) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	214 context->regs[REG_PC] += sign_extend(a << 4 \| b) * 2;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	215 context->state = STATE_NEED_FETCH;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	216 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	217 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	218
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	219 uint16_t format_immediate_bitwise(uint16_t val)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	220 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	221 if (val & 8) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	222 val \|= 0xFFF0;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	223 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	224 return val;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	225 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	226
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	227 uint16_t format_immediate(uint16_t val)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	228 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	229 val = format_immediate_bitwise(val);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	230 if (!val) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	231 val = 8;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	232 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	233 return val;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	234 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	235
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	236 void run_single_reg(cpu *context, uint8_t dst, uint8_t op)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	237 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	238 switch(op)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	239 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	240 case RETI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	241 context->regs[dst] = context->exception_ur;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	242 context->regs[REG_PC] = context->exception_pc;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	243 context->regs[REG_SR] = context->exception_sr;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	244 context->state = STATE_NEED_FETCH;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	245 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	246 case TRAP:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	247 context->state = STATE_EXCEPTION_START;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	248 context->exception = context->regs[dst];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	249 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	250 case TRAPI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	251 context->state = STATE_EXCEPTION_START;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	252 context->exception = dst;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	253 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	254 case GETEPC:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	255 context->regs[dst] = context->exception_pc;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	256 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	257 case SETEPC:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	258 context->exception_pc = context->regs[dst];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	259 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	260 case GETESR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	261 context->regs[dst] = context->exception_sr;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	262 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	263 case SETESR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	264 context->exception_sr = context->regs[dst];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	265 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	266 case GETEUR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	267 context->regs[dst] = context->exception_ur;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	268 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	269 case SETEUR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	270 context->exception_ur = context->regs[dst];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	271 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	272 case GETENUM:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	273 context->regs[dst] = context->exception;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	274 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	275 case SETENUM:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	276 context->exception = context->regs[dst];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	277 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	278 default:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	279 context->state = STATE_EXCEPTION_START;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	280 context->exception = EXCEPTION_INVALID_INSTRUCTION;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	281 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	282 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	283 if (dst == REG_PC) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	284 context->state = STATE_NEED_FETCH;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	285 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	286 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	287
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	288 void run_single_source(cpu *context, uint8_t dst, uint8_t a, uint8_t op)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	289 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	290 uint32_t tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	291 uint8_t shift;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	292 switch(op)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	293 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	294 case MOVE:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	295 context->regs[dst] = context->regs[a];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	296 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	297 case NEG:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	298 tmp = -context->regs[a];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	299 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	300 update_flags_arith(context, tmp);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	301 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	302 case NOT:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	303 context->regs[dst] = ~context->regs[a];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	304 update_flags_bitwise(context, context->regs[dst]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	305 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	306 case CMP:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	307 tmp = context->regs[dst] - context->regs[a];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	308 update_flags_arith(context, tmp);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	309 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	310 case CALL:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	311 context->regs[dst] = context->regs[REG_PC] - 2;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	312 context->regs[REG_PC] = context->regs[a];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	313 context->state = STATE_NEED_FETCH;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	314 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	315 case SWAP:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	316 tmp = context->regs[dst];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	317 context->regs[dst] = context->regs[a];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	318 context->regs[a] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	319 if (a == REG_PC) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	320 context->state = STATE_NEED_FETCH;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	321 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	322 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	323 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	324 case IN:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	325 context->regs[dst] = cpu_read_port(context, context->regs[a]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	326 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	327 case OUT:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	328 cpu_write_port(context, context->regs[a], context->regs[dst]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	329 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	330 case INI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	331 context->regs[dst] = cpu_read_port(context, a);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	332 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	333 case OUTI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	334 cpu_write_port(context, a, context->regs[dst]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	335 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	336 case ADDI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	337 tmp = context->regs[dst] + format_immediate(a);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	338 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	339 update_flags_arith(context, tmp);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	340 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	341 case ANDI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	342 context->regs[dst] = context->regs[dst] & format_immediate_bitwise(a);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	343 update_flags_bitwise(context, context->regs[dst]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	344 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	345 case ORI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	346 context->regs[dst] = context->regs[dst] \| format_immediate_bitwise(a);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	347 update_flags_bitwise(context, context->regs[dst]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	348 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	349 case LSI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	350 shift = a & 7;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	351 if (!shift) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	352 shift = 8;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	353 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	354 if (a & 8) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	355 tmp = context->regs[dst] >> shift;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	356 tmp \|= (context->regs[dst] >> (shift - 1)) << 16 & 0x10000;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	357 } else {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	358 tmp = context->regs[dst] << (a & 7);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	359 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	360 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	361 update_flags_arith(context, tmp);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	362 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	363 case ASRI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	364 shift = a;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	365 if (!shift) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	366 shift = 16;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	367 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	368 tmp = context->regs[dst];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	369 if (tmp & 0x8000) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	370 tmp \|= 0xFFFF0000;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	371 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	372 tmp = tmp >> shift & 0xFFFF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	373 tmp \|= (context->regs[dst] >> (context->regs[shift] - 1)) << 16 & 0x10000;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	374 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	375 update_flags_arith(context, tmp);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	376 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	377 case SINGLE_REG:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	378 run_single_reg(context, dst, a);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	379 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	380 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	381 if (dst == REG_PC) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	382 context->state = STATE_NEED_FETCH;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	383 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	384 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	385
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	386 char * mnemonics[] = {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	387 "ldim", "ldimh", "ld8", "ld16", "str8", "str16", "add", "adc", "and", "or", "xor", "lsl", "lsr", "asr", "bcc", "single"
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	388 };
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	389
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	390 void run_instruction(cpu *context)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	391 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	392 uint16_t instruction = context->prefetch;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	393 fetch_instruction(context);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	394 uint8_t dst = instruction >> 12;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	395 uint8_t a = instruction >> 8 & 0xF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	396 uint8_t b = instruction >> 4 & 0xF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	397 uint8_t op = instruction & 0xF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	398 uint32_t tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	399 switch (op)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	400 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	401 case LDIM:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	402 context->regs[dst] = sign_extend(a << 4 \| b);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	403 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	404 case LDIMH:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	405 context->regs[dst] &= 0xFF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	406 context->regs[dst] \|= a << 12 \| b << 8;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	407 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	408 case LD8:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	409 context->regs[dst] = cpu_read_8(context, context->regs[a] + context->regs[b]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	410 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	411 case LD16:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	412 context->regs[dst] = cpu_read_16(context, context->regs[a] + context->regs[b]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	413 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	414 case STR8:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	415 cpu_write_8(context, context->regs[a] + context->regs[b], context->regs[dst]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	416 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	417 case STR16:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	418 cpu_write_16(context, context->regs[a] + context->regs[b], context->regs[dst]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	419 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	420 case ADD:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	421 tmp = context->regs[a] + context->regs[b];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	422 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	423 update_flags_arith(context, tmp);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	424 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	425 case ADC:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	426 tmp = context->regs[a] + context->regs[b] + (context->regs[REG_SR] & FLAG_C ? 1 : 0);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	427 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	428 update_flags_arith(context, tmp);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	429 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	430 case AND:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	431 context->regs[dst] = context->regs[a] & context->regs[b];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	432 update_flags_bitwise(context, context->regs[dst]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	433 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	434 case OR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	435 context->regs[dst] = context->regs[a] \| context->regs[b];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	436 update_flags_bitwise(context, context->regs[dst]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	437 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	438 case XOR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	439 context->regs[dst] = context->regs[a] ^ context->regs[b];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	440 update_flags_bitwise(context, context->regs[dst]);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	441 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	442 case LSL:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	443 tmp = context->regs[a] << context->regs[b];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	444 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	445 update_flags_arith(context, tmp);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	446 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	447 case LSR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	448 tmp = context->regs[a] >> context->regs[b];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	449 tmp \|= (context->regs[a] >> (context->regs[b] - 1)) << 16 & 0x10000;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	450 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	451 update_flags_arith(context, tmp);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	452 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	453 case ASR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	454 tmp = context->regs[a];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	455 if (tmp & 0x8000) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	456 tmp \|= 0xFFFF0000;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	457 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	458 tmp = tmp >> context->regs[b] & 0xFFFF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	459 tmp \|= (context->regs[a] >> (context->regs[b] - 1)) << 16 & 0x10000;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	460 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	461 update_flags_arith(context, tmp);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	462 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	463 case BCC:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	464 run_bcc(context, dst, a, b);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	465 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	466 case SINGLE_SOURCE:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	467 run_single_source(context, dst, a, b);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	468 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	469 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	470 if (dst == REG_PC) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	471 context->state = STATE_NEED_FETCH;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	472 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	473 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	474
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	475 void run_cpu(cpu *context, uint32_t target_cycle)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	476 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	477 while (context->cycles < target_cycle)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	478 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	479 switch (context->state)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	480 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	481 case STATE_NEED_FETCH:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	482 fetch_instruction(context);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	483 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	484 case STATE_NORMAL:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	485 run_instruction(context);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	486 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	487 case STATE_EXCEPTION_START:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	488 vector_fetch(context);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	489 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	490 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	491 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	492 }

Mercurial > repos > simple16

annotate src/cpu.c @ 0:7e44f7d5810b