repos/simple16: src/cpu.c annotate

annotate src/cpu.c @ 5:18b66690ae13

Removed redundant definitino of some exception register instructinos in spec

author	Michael Pavone <pavone@retrodev.com>
date	Sat, 26 Mar 2016 23:30:50 -0700
parents	6204c81e2933
children	74a6d629b78f

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
2 6204c81e2933 Revert changes to handling of immediate versions of bitwise instructions. Replace asri with cmpi. Michael Pavone <pavone@retrodev.com> parents: 0 diff changeset	219 uint16_t format_immediate(uint16_t val)
0 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 if (!val) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	225 val = 8;
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 return 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
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	230 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	231 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	232 switch(op)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	233 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	234 case RETI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	235 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	236 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	237 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	238 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	239 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	240 case TRAP:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	241 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	242 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	243 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	244 case TRAPI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	245 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	246 context->exception = dst;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	247 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	248 case GETEPC:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	249 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	250 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	251 case SETEPC:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	252 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	253 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	254 case GETESR:
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_sr;
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 SETESR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	258 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	259 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	260 case GETEUR:
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_ur;
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 SETEUR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	264 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	265 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	266 case GETENUM:
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;
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 SETENUM:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	270 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	271 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	272 default:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	273 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	274 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	275 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	276 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	277 if (dst == REG_PC) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	278 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	279 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	280 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	281
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	282 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	283 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	284 uint32_t tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	285 uint8_t shift;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	286 switch(op)
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 case MOVE:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	289 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	290 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	291 case NEG:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	292 tmp = -context->regs[a];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	293 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	294 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	295 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	296 case NOT:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	297 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	298 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	299 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	300 case CMP:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	301 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	302 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	303 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	304 case CALL:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	305 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	306 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	307 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	308 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	309 case SWAP:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	310 tmp = context->regs[dst];
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[a];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	312 context->regs[a] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	313 if (a == REG_PC) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	314 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	315 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	316 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	317 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	318 case IN:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	319 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	320 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	321 case OUT:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	322 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	323 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	324 case INI:
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, 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 OUTI:
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, 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 ADDI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	331 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	332 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	333 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	334 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	335 case ANDI:
2 6204c81e2933 Revert changes to handling of immediate versions of bitwise instructions. Replace asri with cmpi. Michael Pavone <pavone@retrodev.com> parents: 0 diff changeset	336 context->regs[dst] = context->regs[dst] & format_immediate(a);
0 7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	337 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	338 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	339 case ORI:
2 6204c81e2933 Revert changes to handling of immediate versions of bitwise instructions. Replace asri with cmpi. Michael Pavone <pavone@retrodev.com> parents: 0 diff changeset	340 context->regs[dst] = context->regs[dst] \| format_immediate(a);
0 7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	341 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	342 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	343 case LSI:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	344 shift = a & 7;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	345 if (!shift) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	346 shift = 8;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	347 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	348 if (a & 8) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	349 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	350 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	351 } else {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	352 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	353 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	354 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	355 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	356 break;
2 6204c81e2933 Revert changes to handling of immediate versions of bitwise instructions. Replace asri with cmpi. Michael Pavone <pavone@retrodev.com> parents: 0 diff changeset	357 case CMPI:
6204c81e2933 Revert changes to handling of immediate versions of bitwise instructions. Replace asri with cmpi. Michael Pavone <pavone@retrodev.com> parents: 0 diff changeset	358 tmp = a;
6204c81e2933 Revert changes to handling of immediate versions of bitwise instructions. Replace asri with cmpi. Michael Pavone <pavone@retrodev.com> parents: 0 diff changeset	359 if (a & 8) {
6204c81e2933 Revert changes to handling of immediate versions of bitwise instructions. Replace asri with cmpi. Michael Pavone <pavone@retrodev.com> parents: 0 diff changeset	360 a \|= 0xFFF0;
0 7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	361 }
2 6204c81e2933 Revert changes to handling of immediate versions of bitwise instructions. Replace asri with cmpi. Michael Pavone <pavone@retrodev.com> parents: 0 diff changeset	362 tmp = context->regs[dst] - a;
0 7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	363 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	364 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	365 case SINGLE_REG:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	366 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	367 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	368 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	369 if (dst == REG_PC) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	370 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	371 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	372 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	373
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	374 char * mnemonics[] = {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	375 "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	376 };
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	377
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	378 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	379 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	380 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	381 fetch_instruction(context);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	382 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	383 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	384 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	385 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	386 uint32_t tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	387 switch (op)
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 case LDIM:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	390 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	391 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	392 case LDIMH:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	393 context->regs[dst] &= 0xFF;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	394 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	395 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	396 case LD8:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	397 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	398 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	399 case LD16:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	400 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	401 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	402 case STR8:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	403 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	404 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	405 case STR16:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	406 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	407 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	408 case ADD:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	409 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	410 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	411 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	412 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	413 case ADC:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	414 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	415 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	416 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	417 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	418 case AND:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	419 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	420 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	421 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	422 case OR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	423 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	424 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	425 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	426 case XOR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	427 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	428 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	429 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	430 case LSL:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	431 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	432 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	433 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	434 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	435 case LSR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	436 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	437 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	438 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	439 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	440 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	441 case ASR:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	442 tmp = context->regs[a];
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	443 if (tmp & 0x8000) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	444 tmp \|= 0xFFFF0000;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	445 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	446 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	447 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	448 context->regs[dst] = tmp;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	449 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	450 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	451 case BCC:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	452 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	453 return;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	454 case SINGLE_SOURCE:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	455 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	456 return;
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 if (dst == REG_PC) {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	459 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	460 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	461 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	462
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	463 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	464 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	465 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	466 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	467 switch (context->state)
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	468 {
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	469 case STATE_NEED_FETCH:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	470 fetch_instruction(context);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	471 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	472 case STATE_NORMAL:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	473 run_instruction(context);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	474 break;
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	475 case STATE_EXCEPTION_START:
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	476 vector_fetch(context);
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	477 break;
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 }
7e44f7d5810b Initial commit. CPU working well enough for simple hello world program. Michael Pavone <pavone@retrodev.com> parents: diff changeset	480 }

Mercurial > repos > simple16

annotate src/cpu.c @ 5:18b66690ae13