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https://github.com/st3fan/ewm.git
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Fixes #9 - Implement configurable memory regions
This commit is contained in:
Stefan Arentz
parent
b0972be3c8
commit
670ed8b041
198
cpu.c
198
cpu.c
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@ -20,6 +20,7 @@
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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// SOFTWARE.
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#include <assert.h>
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#include <stdio.h>
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#include <string.h>
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#include <stdint.h>
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@ -32,6 +33,7 @@
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#include "cpu.h"
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#include "ins.h"
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#include "mem.h"
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/* Private API */
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@ -39,30 +41,10 @@ typedef void (*cpu_instruction_handler_t)(struct cpu_t *cpu);
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typedef void (*cpu_instruction_handler_byte_t)(struct cpu_t *cpu, uint8_t oper);
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typedef void (*cpu_instruction_handler_word_t)(struct cpu_t *cpu, uint16_t oper);
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// The following get and set memory directly. There are no checks, so
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// make sure you are doing the right thing. Mainly used for managing
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// the stack, reading instructions, reading vectors and tracing code.
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uint8_t _mem_get_byte(struct cpu_t *cpu, uint16_t addr) {
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return cpu->memory[addr];
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}
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uint16_t _mem_get_word(struct cpu_t *cpu, uint16_t addr) {
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return *((uint16_t*) &cpu->memory[addr]);
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}
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void _mem_set_byte(struct cpu_t *cpu, uint16_t addr, uint8_t v) {
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cpu->memory[addr] = v;
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}
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void _mem_set_word(struct cpu_t *cpu, uint16_t addr, uint8_t v) {
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*((uint16_t*) &cpu->memory[addr]) = v;
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}
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// Stack management.
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void _cpu_push_byte(struct cpu_t *cpu, uint8_t b) {
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_mem_set_byte(cpu, 0x0100 + cpu->state.sp, b);
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_mem_set_byte_direct(cpu, 0x0100 + cpu->state.sp, b);
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cpu->state.sp -= 1;
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}
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@ -73,7 +55,7 @@ void _cpu_push_word(struct cpu_t *cpu, uint16_t w) {
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uint8_t _cpu_pull_byte(struct cpu_t *cpu) {
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cpu->state.sp += 1;
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return _mem_get_byte(cpu, 0x0100 + cpu->state.sp);
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return _mem_get_byte_direct(cpu, 0x0100 + cpu->state.sp);
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}
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uint16_t _cpu_pull_word(struct cpu_t *cpu) {
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@ -107,12 +89,11 @@ void _cpu_set_status(struct cpu_t *cpu, uint8_t status) {
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cpu->state.c = (status & (1 << 0));
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}
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#if 1
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static void cpu_format_instruction(struct cpu_t *cpu, char *buffer) {
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*buffer = 0x00;
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cpu_instruction_t *i = &instructions[cpu->memory[cpu->state.pc]];
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uint8_t opcode = cpu->memory[cpu->state.pc];
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cpu_instruction_t *i = &instructions[mem_get_byte(cpu, cpu->state.pc)];
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uint8_t opcode = mem_get_byte(cpu, cpu->state.pc);
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/* Single byte instructions */
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if (i->bytes == 1) {
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@ -121,12 +102,12 @@ static void cpu_format_instruction(struct cpu_t *cpu, char *buffer) {
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/* JSR is the only exception */
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else if (opcode == 0x20) {
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sprintf(buffer, "%s $%.4X", i->name, _mem_get_word(cpu, cpu->state.pc+1));
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sprintf(buffer, "%s $%.4X", i->name, mem_get_word(cpu, cpu->state.pc+1));
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}
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/* Branches */
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else if ((opcode & 0b00011111) == 0b00010000) {
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int8_t offset = (int8_t) _mem_get_byte(cpu, cpu->state.pc+1);
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int8_t offset = (int8_t) mem_get_byte(cpu, cpu->state.pc+1);
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uint16_t addr = cpu->state.pc + 2 + offset;
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sprintf(buffer, "%s $%.4X", i->name, addr);
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}
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@ -134,28 +115,28 @@ static void cpu_format_instruction(struct cpu_t *cpu, char *buffer) {
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else if ((opcode & 0b00000011) == 0b00000001) {
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switch ((opcode & 0b00011100) >> 2) {
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case 0b000:
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sprintf(buffer, "%s ($%.2X,X)", i->name, cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s ($%.2X,X)", i->name, mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b001:
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sprintf(buffer, "%s $%.2X", i->name, cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b010:
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sprintf(buffer, "%s #$%.2X", i->name, cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s #$%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b011:
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sprintf(buffer, "%s $%.2X%.2X", i->name, cpu->memory[cpu->state.pc+2], cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b100:
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sprintf(buffer, "%s ($%.2X),Y", i->name, cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s ($%.2X),Y", i->name, mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b101:
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sprintf(buffer, "%s $%.2X,X", i->name, cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b110:
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sprintf(buffer, "%s $%.2X%.2X,Y", i->name, cpu->memory[cpu->state.pc+2], cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X%.2X,Y", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b111:
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sprintf(buffer, "%s $%.2X%.2X,X", i->name, cpu->memory[cpu->state.pc+2], cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
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break;
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}
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}
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@ -163,22 +144,22 @@ static void cpu_format_instruction(struct cpu_t *cpu, char *buffer) {
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else if ((opcode & 0b00000011) == 0b00000010) {
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switch ((opcode & 0b00011100) >> 2) {
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case 0b000:
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sprintf(buffer, "%s #$%.2X", i->name, cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s #$%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b001:
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sprintf(buffer, "%s $%.2X", i->name, cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b010:
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sprintf(buffer, "%s", i->name);
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break;
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case 0b011:
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sprintf(buffer, "%s $%.2X%.2X", i->name, cpu->memory[cpu->state.pc+2], cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b101:
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sprintf(buffer, "%s $%.2X,X", i->name, cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b111:
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sprintf(buffer, "%s $%.2X%.2X,X", i->name, cpu->memory[cpu->state.pc+2], cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
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break;
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}
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}
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@ -186,19 +167,19 @@ static void cpu_format_instruction(struct cpu_t *cpu, char *buffer) {
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else if ((opcode & 0b00000011) == 0b00000000) {
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switch ((opcode & 0b00011100) >> 2) {
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case 0b000:
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sprintf(buffer, "%s #$%.2X", i->name, cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s #$%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b001:
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sprintf(buffer, "%s $%.2X", i->name, cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b011:
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sprintf(buffer, "%s $%.2X%.2X", i->name, cpu->memory[cpu->state.pc+2], cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X%.2X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b101:
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sprintf(buffer, "%s $%.2X,X", i->name, cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+1));
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break;
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case 0b111:
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sprintf(buffer, "%s $%.2X%.2X,X", i->name, cpu->memory[cpu->state.pc+2], cpu->memory[cpu->state.pc+1]);
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sprintf(buffer, "%s $%.2X%.2X,X", i->name, mem_get_byte(cpu, cpu->state.pc+2), mem_get_byte(cpu, cpu->state.pc+1));
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break;
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}
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}
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@ -222,11 +203,10 @@ static void cpu_format_stack(struct cpu_t *cpu, char *buffer) {
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*buffer = 0x00;
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for (uint16_t sp = cpu->state.sp; sp != 0xff; sp++) {
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char tmp[8];
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sprintf(tmp, " %.2X", _mem_get_byte(cpu, 0x0100 + sp));
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sprintf(tmp, " %.2X", _mem_get_byte_direct(cpu, 0x0100 + sp));
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buffer = strcat(buffer, tmp);
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}
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}
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#endif
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static mach_timebase_info_data_t timebase_info;
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@ -239,8 +219,6 @@ static uint64_t nanos_to_abs(uint64_t nanos) {
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}
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static int cpu_execute_instruction(struct cpu_t *cpu) {
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/* Trace code - Refactor into its own function or module */
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char trace_instruction[256];
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char trace_state[256];
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@ -250,11 +228,10 @@ static int cpu_execute_instruction(struct cpu_t *cpu) {
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cpu_format_instruction(cpu, trace_instruction);
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}
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uint64_t start_time = mach_absolute_time();
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/* Fetch instruction */
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cpu_instruction_t *i = &instructions[cpu->memory[cpu->state.pc]];
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cpu_instruction_t *i = &instructions[mem_get_byte(cpu, cpu->state.pc)];
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/* Remember the PC since some instructions modify it */
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uint16_t pc = cpu->state.pc;
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@ -270,14 +247,13 @@ static int cpu_execute_instruction(struct cpu_t *cpu) {
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((cpu_instruction_handler_t) i->handler)(cpu);
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break;
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case 2:
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((cpu_instruction_handler_byte_t) i->handler)(cpu, _mem_get_byte(cpu, pc+1));
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((cpu_instruction_handler_byte_t) i->handler)(cpu, mem_get_byte(cpu, pc+1));
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break;
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case 3:
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((cpu_instruction_handler_word_t) i->handler)(cpu, _mem_get_word(cpu, pc+1));
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((cpu_instruction_handler_word_t) i->handler)(cpu, mem_get_word(cpu, pc+1));
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break;
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}
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if (cpu->trace) {
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cpu_format_state(cpu, trace_state);
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cpu_format_stack(cpu, trace_stack); // TODO: This crashes on the hello world test
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@ -285,24 +261,19 @@ static int cpu_execute_instruction(struct cpu_t *cpu) {
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switch (i->bytes) {
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case 1:
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fprintf(stderr, "CPU: %.4X %-20s | %.2X %-20s STACK: %s\n",
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pc, trace_instruction, cpu->memory[pc], trace_state, trace_stack);
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pc, trace_instruction, mem_get_byte(cpu, pc), trace_state, trace_stack);
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break;
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case 2:
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fprintf(stderr, "CPU: %.4X %-20s | %.2X %.2X %-20s STACK: %s\n",
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pc, trace_instruction, cpu->memory[pc], cpu->memory[pc+1], trace_state, trace_stack);
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pc, trace_instruction, mem_get_byte(cpu, pc), mem_get_byte(cpu, pc+1), trace_state, trace_stack);
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break;
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case 3:
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fprintf(stderr, "CPU: %.4X %-20s | %.2X %.2X %.2X %-20s STACK: %s\n",
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pc, trace_instruction, cpu->memory[pc], cpu->memory[pc+1], cpu->memory[pc+2], trace_state, trace_stack);
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pc, trace_instruction, mem_get_byte(cpu, pc), mem_get_byte(cpu, pc+1), mem_get_byte(cpu, pc+2), trace_state, trace_stack);
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break;
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}
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}
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/* Delay */
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if (timebase_info.denom == 0) {
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@ -322,42 +293,88 @@ static int cpu_execute_instruction(struct cpu_t *cpu) {
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return i->opcode;
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}
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static void iom_init(struct iom_t *iom, uint16_t start, uint16_t length, void *obj, iom_read_handler_t read_handler, iom_write_handler_t write_handler) {
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memset(iom, 0x00, sizeof(struct iom_t));
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iom->start = start;
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iom->length = length;
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iom->obj = obj;
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iom->read_handler = read_handler;
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iom->write_handler = write_handler;
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}
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/* Public API */
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void cpu_init(struct cpu_t *cpu) {
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memset(cpu, 0x00, sizeof(struct cpu_t));
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cpu->memory = malloc(64 * 1024);
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}
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void cpu_add_ram(struct cpu_t *cpu, uint16_t start, uint16_t length, uint8_t *data) {
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if (data != NULL) {
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memcpy(cpu->memory + start, data, length);
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}
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/* TODO: Mark pages as RAM */
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void cpu_add_mem(struct cpu_t *cpu, struct mem_t *mem) {
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if (cpu->mem == NULL) {
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cpu->mem = mem;
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mem->next = NULL;
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} else {
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mem->next = cpu->mem;
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cpu->mem = mem;
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}
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// If this is RAM mapped to the zero-page and to the stack then we
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// keep a shortcut to it so that we can do direct and fast access
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// with our _mem_get/set_byte/word_direct functions.
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//
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// This makes two assumptions: when RAM is added, it covers both
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// pages. And that mem->obj points to a block of memory. This is
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// fine for the Apple I and Apple II emulators.
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if (mem->type == MEM_TYPE_RAM) {
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if (mem->start == 0x0000 && mem->length >= 0x200) {
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cpu->memory = mem->obj;
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}
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}
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}
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// RAM Memory
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static uint8_t _ram_read(struct cpu_t *cpu, struct mem_t *mem, uint16_t addr) {
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return ((uint8_t*) mem->obj)[addr - mem->start];
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}
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static void _ram_write(struct cpu_t *cpu, struct mem_t *mem, uint16_t addr, uint8_t b) {
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((uint8_t*) mem->obj)[addr - mem->start] = b;
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}
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void cpu_add_ram(struct cpu_t *cpu, uint16_t start, uint16_t length) {
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struct mem_t *mem = (struct mem_t*) malloc(sizeof(struct mem_t));
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mem->type = MEM_TYPE_RAM;
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mem->obj = malloc(length);
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mem->start = start;
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mem->length = length;
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mem->read_handler = _ram_read;
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mem->write_handler = _ram_write;
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mem->next = NULL;
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cpu_add_mem(cpu, mem);
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}
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// ROM Memory
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static uint8_t _rom_read(struct cpu_t *cpu, struct mem_t *mem, uint16_t addr) {
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return ((uint8_t*) mem->obj)[addr - mem->start];
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}
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void cpu_add_rom(struct cpu_t *cpu, uint16_t start, uint16_t length, uint8_t *data) {
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if (data != NULL) {
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memcpy(cpu->memory + start, data, length);
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}
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/* TODO: Mark pages as ROM */
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struct mem_t *mem = (struct mem_t*) malloc(sizeof(struct mem_t));
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mem->type = MEM_TYPE_ROM;
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mem->obj = data;
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mem->start = start;
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mem->length = length;
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mem->read_handler = _rom_read;
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mem->write_handler = NULL;
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mem->next = NULL;
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cpu_add_mem(cpu, mem);
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}
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void cpu_add_iom(struct cpu_t *cpu, uint16_t start, uint16_t length, void *obj, iom_read_handler_t read_handler, iom_write_handler_t write_handler) {
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struct iom_t *iom = (struct iom_t*) malloc(sizeof(struct iom_t));
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iom_init(iom, start, length, obj, read_handler, write_handler);
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iom->next = (struct iom_t*) cpu->iom;
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cpu->iom = iom;
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/* TODO: Mark pages as IO */
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// IO Memory
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void cpu_add_iom(struct cpu_t *cpu, uint16_t start, uint16_t length, void *obj, mem_read_handler_t read_handler, mem_write_handler_t write_handler) {
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struct mem_t *mem = (struct mem_t*) malloc(sizeof(struct mem_t));
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mem->type = MEM_TYPE_IOM;
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mem->obj = obj;
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mem->start = start;
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mem->length = length;
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mem->read_handler = read_handler;
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mem->write_handler = write_handler;
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mem->next = NULL;
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cpu_add_mem(cpu, mem);
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}
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void cpu_trace(struct cpu_t *cpu, uint8_t trace) {
|
||||
|
|
@ -365,7 +382,8 @@ void cpu_trace(struct cpu_t *cpu, uint8_t trace) {
|
|||
}
|
||||
|
||||
void cpu_reset(struct cpu_t *cpu) {
|
||||
cpu->state.pc = _mem_get_word(cpu, 0xfffc);
|
||||
cpu->state.pc = mem_get_word(cpu, 0xfffc);
|
||||
fprintf(stderr, "CPU: cpu->state.pc = %.4x\n", cpu->state.pc);
|
||||
cpu->state.a = 0x00;
|
||||
cpu->state.x = 0x00;
|
||||
cpu->state.y = 0x00;
|
||||
|
|
@ -383,14 +401,14 @@ void cpu_irq(struct cpu_t *cpu) {
|
|||
_cpu_push_word(cpu, cpu->state.pc);
|
||||
_cpu_push_byte(cpu, _cpu_get_status(cpu));
|
||||
cpu->state.i = 1;
|
||||
cpu->state.pc = _mem_get_word(cpu, 0xfffe);
|
||||
cpu->state.pc = mem_get_word(cpu, 0xfffe);
|
||||
}
|
||||
|
||||
void cpu_nmi(struct cpu_t *cpu) {
|
||||
_cpu_push_word(cpu, cpu->state.pc);
|
||||
_cpu_push_byte(cpu, _cpu_get_status(cpu));
|
||||
cpu->state.i = 1;
|
||||
cpu->state.pc = _mem_get_word(cpu, 0xfffa);
|
||||
cpu->state.pc = mem_get_word(cpu, 0xfffa);
|
||||
}
|
||||
|
||||
void cpu_run(struct cpu_t *cpu) {
|
||||
|
|
|
|||
43
cpu.h
43
cpu.h
|
|
@ -25,15 +25,6 @@
|
|||
|
||||
#include <stdint.h>
|
||||
|
||||
struct iom_t {
|
||||
uint16_t start;
|
||||
uint16_t length;
|
||||
void *obj;
|
||||
void *read_handler;
|
||||
void *write_handler;
|
||||
struct iom_t *next;
|
||||
};
|
||||
|
||||
struct cpu_state_t {
|
||||
uint8_t a, x, y, s, sp;
|
||||
uint16_t pc;
|
||||
|
|
@ -42,16 +33,27 @@ struct cpu_state_t {
|
|||
|
||||
struct cpu_t {
|
||||
struct cpu_state_t state;
|
||||
uint8_t *memory;
|
||||
uint8_t trace;
|
||||
struct iom_t *iom;
|
||||
struct mem_t *mem;
|
||||
uint8_t *memory; // This is pointing to the first 2 pages of memory, zero page and stack.
|
||||
};
|
||||
|
||||
// Private. How do we keep them private?
|
||||
uint8_t _mem_get_byte(struct cpu_t *cpu, uint16_t addr);
|
||||
uint16_t _mem_get_word(struct cpu_t *cpu, uint16_t addr);
|
||||
void _mem_set_byte(struct cpu_t *cpu, uint16_t addr, uint8_t v);
|
||||
void _mem_set_word(struct cpu_t *cpu, uint16_t addr, uint8_t v);
|
||||
#define MEM_TYPE_RAM 0
|
||||
#define MEM_TYPE_ROM 1
|
||||
#define MEM_TYPE_IOM 2
|
||||
|
||||
typedef uint8_t (*mem_read_handler_t)(struct cpu_t *cpu, struct mem_t *mem, uint16_t addr);
|
||||
typedef void (*mem_write_handler_t)(struct cpu_t *cpu, struct mem_t *mem, uint16_t addr, uint8_t b);
|
||||
|
||||
struct mem_t {
|
||||
uint8_t type;
|
||||
uint16_t start;
|
||||
uint16_t length;
|
||||
void *obj;
|
||||
mem_read_handler_t read_handler;
|
||||
mem_write_handler_t write_handler;
|
||||
struct mem_t *next;
|
||||
};
|
||||
|
||||
// Private. How do we keep them private?
|
||||
void _cpu_push_byte(struct cpu_t *cpu, uint8_t b);
|
||||
|
|
@ -63,13 +65,12 @@ uint16_t _cpu_pull_word(struct cpu_t *cpu);
|
|||
uint8_t _cpu_get_status(struct cpu_t *cpu);
|
||||
void _cpu_set_status(struct cpu_t *cpu, uint8_t status);
|
||||
|
||||
typedef uint8_t (*iom_read_handler_t)(struct cpu_t *cpu, void *obj, uint16_t addr);
|
||||
typedef void (*iom_write_handler_t)(struct cpu_t *cpu, void *obj, uint16_t addr, uint8_t b);
|
||||
|
||||
void cpu_init(struct cpu_t *cpu);
|
||||
void cpu_add_ram(struct cpu_t *cpu, uint16_t start, uint16_t length, uint8_t *data);
|
||||
|
||||
void cpu_add_mem(struct cpu_t *cpu, struct mem_t *mem);
|
||||
void cpu_add_ram(struct cpu_t *cpu, uint16_t start, uint16_t length);
|
||||
void cpu_add_rom(struct cpu_t *cpu, uint16_t start, uint16_t length, uint8_t *data);
|
||||
void cpu_add_iom(struct cpu_t *cpu, uint16_t start, uint16_t length, void *obj, iom_read_handler_t read_handler, iom_write_handler_t write_handler);
|
||||
void cpu_add_iom(struct cpu_t *cpu, uint16_t start, uint16_t length, void *obj, mem_read_handler_t read_handler, mem_write_handler_t write_handler);
|
||||
|
||||
void cpu_trace(struct cpu_t *cpu, uint8_t trace);
|
||||
|
||||
|
|
|
|||
4
ewm.c
4
ewm.c
|
|
@ -70,9 +70,9 @@ int main(int argc, char **argv) {
|
|||
|
||||
struct cpu_t cpu;
|
||||
cpu_init(&cpu);
|
||||
cpu_add_ram(&cpu, 0x0000, 0x4000, NULL);
|
||||
cpu_add_iom(&cpu, 0xd000, 0x1000, &pia, pia_read, pia_write);
|
||||
cpu_add_ram(&cpu, 0x0000, 0x4000);
|
||||
cpu_add_rom(&cpu, 0xff00, 0x0100, monitor);
|
||||
cpu_add_iom(&cpu, 0xd000, 0x1000, &pia, pia_read, pia_write);
|
||||
cpu_trace(&cpu, 0);
|
||||
cpu_boot(&cpu);
|
||||
|
||||
|
|
|
|||
89
mem.c
89
mem.c
|
|
@ -20,23 +20,50 @@
|
|||
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
||||
// SOFTWARE.
|
||||
|
||||
#include <assert.h>
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
|
||||
#include "mem.h"
|
||||
|
||||
/* Memory Access */
|
||||
// The following two are our memory primitives that properly set go
|
||||
// through the handler functions for all registered memory. They will
|
||||
// take more time but do the right thing.
|
||||
|
||||
uint8_t mem_get_byte(struct cpu_t *cpu, uint16_t addr) {
|
||||
if (cpu->iom) {
|
||||
/* TODO: Assuming there is only one area of memory mapped io */
|
||||
if (addr >= cpu->iom->start && addr < (cpu->iom->start + cpu->iom->length)) {
|
||||
uint8_t v = ((iom_read_handler_t) cpu->iom->read_handler)((struct cpu_t*) cpu, cpu->iom->obj, addr);
|
||||
//fprintf(stderr, "MEM: GETTING BYTE AT %.4X -> %.2X\n", addr, v);
|
||||
return v;
|
||||
struct mem_t *mem = cpu->mem;
|
||||
while (mem != NULL) {
|
||||
if (addr >= mem->start && (addr <= (mem->start + mem->length))) {
|
||||
if (mem->read_handler) {
|
||||
return ((mem_read_handler_t) mem->read_handler)((struct cpu_t*) cpu, mem, addr);
|
||||
} else {
|
||||
// TODO What to do?
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
mem = mem->next;
|
||||
}
|
||||
//fprintf(stderr, "MEM: GETTING BYTE AT %.4X -> %.2X\n", addr, cpu->memory[addr]);
|
||||
return cpu->memory[addr];
|
||||
return 0; // TODO What should the default be if we read from non-existent memory?
|
||||
}
|
||||
|
||||
void mem_set_byte(struct cpu_t *cpu, uint16_t addr, uint8_t v) {
|
||||
struct mem_t *mem = cpu->mem;
|
||||
while (mem != NULL) {
|
||||
if (addr >= mem->start && (addr <= (mem->start + mem->length))) {
|
||||
if (mem->write_handler) {
|
||||
((mem_write_handler_t) mem->write_handler)((struct cpu_t*) cpu, mem, addr, v);
|
||||
} else {
|
||||
// TODO What to do?
|
||||
}
|
||||
return;
|
||||
}
|
||||
mem = mem->next;
|
||||
}
|
||||
// TODO What should the default be if we read from non-existent memory?
|
||||
}
|
||||
|
||||
// Getters
|
||||
|
||||
uint8_t mem_get_byte_abs(struct cpu_t *cpu, uint16_t addr) {
|
||||
return mem_get_byte(cpu, addr);
|
||||
}
|
||||
|
|
@ -69,21 +96,12 @@ uint8_t mem_get_byte_indy(struct cpu_t *cpu, uint8_t addr) {
|
|||
return mem_get_byte(cpu, mem_get_word(cpu, addr) + cpu->state.y);
|
||||
}
|
||||
|
||||
|
||||
|
||||
void mem_set_byte(struct cpu_t *cpu, uint16_t addr, uint8_t v) {
|
||||
//fprintf(stderr, "MEM: SETTING BYTE AT %.4X -> %.2X (%c)\n", addr, v, v & 0x7f);
|
||||
if (cpu->iom) {
|
||||
/* TODO: Assuming there is only one area of memory mapped io */
|
||||
if (addr >= cpu->iom->start && addr < (cpu->iom->start + cpu->iom->length)) {
|
||||
((iom_write_handler_t) cpu->iom->write_handler)((struct cpu_t*) cpu, cpu->iom->obj, addr, v);
|
||||
return;
|
||||
}
|
||||
}
|
||||
cpu->memory[addr] = v;
|
||||
uint16_t mem_get_word(struct cpu_t *cpu, uint16_t addr) {
|
||||
// TODO Did I do this right?
|
||||
return ((uint16_t) mem_get_byte(cpu, addr+1) << 8) | (uint16_t) mem_get_byte(cpu, addr);
|
||||
}
|
||||
|
||||
|
||||
// Setters
|
||||
|
||||
void mem_set_byte_zpg(struct cpu_t *cpu, uint8_t addr, uint8_t v) {
|
||||
mem_set_byte(cpu, addr, v);
|
||||
|
|
@ -117,6 +135,11 @@ void mem_set_byte_indy(struct cpu_t *cpu, uint8_t addr, uint8_t v) {
|
|||
mem_set_byte(cpu, mem_get_word(cpu, addr)+cpu->state.y, v);
|
||||
}
|
||||
|
||||
void mem_set_word(struct cpu_t *cpu, uint16_t addr, uint16_t v) {
|
||||
mem_set_byte(cpu, addr+0, (uint8_t) v); // TODO Did I do this right?
|
||||
mem_set_byte(cpu, addr+1, (uint8_t) (v >> 8));
|
||||
}
|
||||
|
||||
/* MOD */
|
||||
|
||||
void mem_mod_byte_zpg(struct cpu_t *cpu, uint8_t addr, mem_mod_t op) {
|
||||
|
|
@ -151,12 +174,26 @@ void mem_mod_byte_indy(struct cpu_t *cpu, uint8_t addr, mem_mod_t op) {
|
|||
mem_set_byte_indy(cpu, addr, op(cpu, mem_get_byte_indy(cpu, addr)));
|
||||
}
|
||||
|
||||
/* Words */
|
||||
// The following get and set memory directly. There are no checks, so
|
||||
// make sure you are doing the right thing. Mainly used for managing
|
||||
// the stack, reading instructions, reading vectors and tracing code.
|
||||
|
||||
uint16_t mem_get_word(struct cpu_t *cpu, uint16_t addr) {
|
||||
uint8_t _mem_get_byte_direct(struct cpu_t *cpu, uint16_t addr) {
|
||||
assert(addr <= 0x200);
|
||||
return cpu->memory[addr];
|
||||
}
|
||||
|
||||
uint16_t _mem_get_word_direct(struct cpu_t *cpu, uint16_t addr) {
|
||||
assert(addr <= 0x200);
|
||||
return *((uint16_t*) &cpu->memory[addr]);
|
||||
}
|
||||
|
||||
void mem_set_word(struct cpu_t *cpu, uint16_t addr, uint16_t v) {
|
||||
*((uint16_t*) &cpu->memory[addr]) = v;
|
||||
void _mem_set_byte_direct(struct cpu_t *cpu, uint16_t addr, uint8_t v) {
|
||||
assert(addr <= 0x200);
|
||||
cpu->memory[addr] = v;
|
||||
}
|
||||
|
||||
void _mem_set_word_direct(struct cpu_t *cpu, uint16_t addr, uint16_t v) {
|
||||
assert(addr <= 0x200);
|
||||
*((uint16_t*) &cpu->memory[addr]) = v;
|
||||
}
|
||||
|
|
|
|||
6
mem.h
6
mem.h
|
|
@ -59,4 +59,10 @@ void mem_mod_byte_indy(struct cpu_t *cpu, uint8_t addr, mem_mod_t op);
|
|||
uint16_t mem_get_word(struct cpu_t *cpu, uint16_t addr);
|
||||
void mem_set_word(struct cpu_t *cpu, uint16_t addr, uint16_t v);
|
||||
|
||||
// Private. How do we keep them private?
|
||||
uint8_t _mem_get_byte_direct(struct cpu_t *cpu, uint16_t addr);
|
||||
uint16_t _mem_get_word_direct(struct cpu_t *cpu, uint16_t addr);
|
||||
void _mem_set_byte_direct(struct cpu_t *cpu, uint16_t addr, uint8_t v);
|
||||
void _mem_set_word_direct(struct cpu_t *cpu, uint16_t addr, uint16_t v);
|
||||
|
||||
#endif
|
||||
|
|
|
|||
8
pia.c
8
pia.c
|
|
@ -61,8 +61,8 @@ void pia_trace(struct pia_t *pia, uint8_t trace) {
|
|||
pia->trace = trace;
|
||||
}
|
||||
|
||||
uint8_t pia_read(struct cpu_t *cpu, void *obj, uint16_t addr) {
|
||||
struct pia_t *pia = (struct pia_t*) obj;
|
||||
uint8_t pia_read(struct cpu_t *cpu, struct mem_t *mem, uint16_t addr) {
|
||||
struct pia_t *pia = (struct pia_t*) mem->obj;
|
||||
uint8_t result = 0;
|
||||
switch (addr) {
|
||||
case 0xd010: /* KBD */
|
||||
|
|
@ -96,8 +96,8 @@ uint8_t pia_read(struct cpu_t *cpu, void *obj, uint16_t addr) {
|
|||
return result;
|
||||
}
|
||||
|
||||
void pia_write(struct cpu_t *cpu, void *obj, uint16_t addr, uint8_t b) {
|
||||
struct pia_t *pia = (struct pia_t*) obj;
|
||||
void pia_write(struct cpu_t *cpu, struct mem_t *mem, uint16_t addr, uint8_t b) {
|
||||
struct pia_t *pia = (struct pia_t*) mem->obj;
|
||||
if (pia->trace) {
|
||||
fprintf(stderr, "PIA: WRITING BYTE %.2X TO %.4X\n", b, addr);
|
||||
}
|
||||
|
|
|
|||
4
pia.h
4
pia.h
|
|
@ -36,7 +36,7 @@ struct pia_t {
|
|||
|
||||
void pia_init(struct pia_t *pia);
|
||||
void pia_trace(struct pia_t *pia, uint8_t trace);
|
||||
uint8_t pia_read(struct cpu_t *cpu, void *obj, uint16_t addr);
|
||||
void pia_write(struct cpu_t *cpu, void *obj, uint16_t addr, uint8_t b);
|
||||
uint8_t pia_read(struct cpu_t *cpu, struct mem_t *mem, uint16_t addr);
|
||||
void pia_write(struct cpu_t *cpu, struct mem_t *mem, uint16_t addr, uint8_t b);
|
||||
|
||||
#endif
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user