xamidev/dumb8
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

OUT/IN instructions

Browse Source
This commit is contained in:
xamidev
2024-10-19 20:58:05 +02:00
parent b46bfc38e1
commit 15b524a436
2 changed files with 47 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

47
cpu.c
View File

@@ -38,6 +38,10 @@ typedef enum
AND = 0xC1,
XOR = 0xC2,
// 0xD? -> Input/output operations
OUT = 0xD0,
IN = 0xD1,
// 0xE? -> Jump and comparisons
JMP = 0xE0,
JEQ = 0xE1,
@@ -152,7 +156,14 @@ void cpu_exec(uint8_t opcode)
cpu.equal_flag = (cpu.reg[reg1] == cpu.reg[reg2]);
cpu.flag_clear_delay = 2;
break;
// TODO: complete instruction set
case OUT:
reg1 = cpu.memory[cpu.pc++];
putchar(cpu.reg[reg1]);
break;
case IN:
reg1 = cpu.memory[cpu.pc++];
cpu.reg[reg1] = getchar();
break;
default:
printf("Unknown instruction: 0x%02X\n", opcode);
cpu.halted = true;
@@ -203,6 +214,7 @@ void assemble(const char* filename)
}
else if (sscanf(line, "%s %[^,], %s", instruction, reg1, reg2) == 3)
{
//printf("SS1");
int reg1_n = reg1[1] - '0';
int reg2_n = reg2[1] - '0';
@@ -247,6 +259,7 @@ void assemble(const char* filename)
}
} else if (sscanf(line, "%s %[^,], %d", instruction, reg1, &addr) == 2)
{
//printf("SS2");
int reg1_n = reg1[1] - '0';
if (strncmp(instruction, "JEQ", 3) == 0)
@@ -257,14 +270,33 @@ void assemble(const char* filename)
}
else if (sscanf(line, "%s %d", instruction, &addr) == 2)
{
//printf("SS3");
if (strncmp(instruction, "JMP", 3) == 0)
{
cpu.memory[mem_index++] = JMP;
cpu.memory[mem_index++] = addr;
}
}
else if (sscanf(line, "%s %s", instruction, reg1) == 2)
{
//printf("SS4");
int reg1_n = reg1[1] - '0';
if (strncmp(instruction, "OUT", 3) == 0)
{
cpu.memory[mem_index++] = OUT;
cpu.memory[mem_index++] = reg1_n;
}
if (strncmp(instruction, "IN", 2) == 0)
{
cpu.memory[mem_index++] = IN;
cpu.memory[mem_index++] = reg1_n;
}
}
}
else if (strncmp(line, "HLT", 3) == 0)
{
cpu.memory[mem_index++] = HLT;
@@ -283,11 +315,13 @@ void assemble(const char* filename)
void cpu_run()
{
printf("\n[BEGIN CPU OUTPUT]\n");
while (!cpu.halted)
{
uint8_t opcode = cpu.memory[cpu.pc++];
cpu_exec(opcode);
}
printf("\n[END CPU OUTPUT]\n");
}
/*
@@ -336,6 +370,10 @@ void mem_dump()
case 0xc2:
printf("\e[45m%02x\e[0m ", cpu.memory[i]);
break;
case 0xd0:
printf("\e[46m%02x\e[0m ", cpu.memory[i]);
break;
case 0xe0:
case 0xe1:
@@ -386,8 +424,9 @@ int main(int argc, char* argv[])
// Dumping our program
mem_dump();
reg_write(1, 0x12);
reg_write(2, 0x10);
reg_write(1, 0x68);
reg_write(2, 0x69);
reg_write(3, 0x21);
cpu_run();
// Post-mortem analysis