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add memory writing functions

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This commit is contained in:
Vineet K 2024-06-09 16:07:09 +05:30
parent 4db0a8163e
commit c417bf2276
1 changed files with 18 additions and 4 deletions
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22
cpu.c
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@ -51,20 +51,34 @@ uint8_t program[] = { 0xa9, 0xc0, 0xaa, 0xe8, 0x00 };
uint32_t cycles = 0; uint32_t cycles = 0;
uint8_t static uint8_t
peek(uint16_t addr) peek(uint16_t addr)
{ {
return memory[addr]; return memory[addr];
} }
uint16_t static uint16_t
peek16(uint16_t addr) peek16(uint16_t addr)
{ {
/* bytes are stored in little-endian (low then high) */ /* bytes are stored in little-endian (low then high) */
return (uint16_t)memory[addr] | ((uint16_t)memory[addr + 1] << 8); return (uint16_t)memory[addr] | ((uint16_t)memory[addr + 1] << 8);
} }
uint8_t static void
memwrite(uint16_t addr, uint8_t byte)
{
memory[addr] = b;
}
static void
memwrite16(uint16_t addr, uint16_t word)
{
/* bytes are stored in little-endian (low then high) */
memory[addr] = word & 0xFF;
memory[addr + 1] = (word & 0xFF00) >> 8;
}
static uint8_t
opcode_arg(enum addressing_mode mode) opcode_arg(enum addressing_mode mode)
{ {
uint8_t arg, val; uint8_t arg, val;
@ -597,7 +611,7 @@ unp(uint8_t arg)
/* TODO: complete this */ /* TODO: complete this */
} }
void static void
interpret(void) interpret(void)
{ {
uint8_t opcode; uint8_t opcode;