diff options
Diffstat (limited to 'src/instruction.ts')
| -rw-r--r-- | src/instruction.ts | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/src/instruction.ts b/src/instruction.ts index 1d016aa..8e52a80 100644 --- a/src/instruction.ts +++ b/src/instruction.ts @@ -204,17 +204,23 @@ export function avrInstruction(cpu: ICPU) { /* LDX, 1001 000d dddd 1100 */ if ((opcode & 0xfe0f) === 0x900c) { - /* not implemented */ + cpu.data[(opcode & 0x1f0) >> 4] = cpu.readData(cpu.dataView.getUint16(26, true)); } /* LDX, 1001 000d dddd 1101 */ if ((opcode & 0xfe0f) === 0x900d) { - /* not implemented */ + const x = cpu.dataView.getUint16(26, true); + cpu.data[(opcode & 0x1f0) >> 4] = x; + cpu.dataView.setUint16(26, x + 1, true); + cpu.cycles++; } /* LDX, 1001 000d dddd 1110 */ if ((opcode & 0xfe0f) === 0x900e) { - /* not implemented */ + const x = cpu.dataView.getUint16(26, true) - 1; + cpu.dataView.setUint16(26, x, true); + cpu.data[(opcode & 0x1f0) >> 4] = cpu.readData(x); + cpu.cycles += 2; } /* LDY, 1000 000d dddd 1000 */ @@ -430,15 +436,17 @@ export function avrInstruction(cpu: ICPU) { /* STX, 1001 001r rrrr 1101 */ if ((opcode & 0xfe0f) === 0x920d) { - cpu.writeData(cpu.dataView.getUint16(26, true), cpu.data[(opcode & 0x1f0) >> 4]); - cpu.dataView.setUint16(26, cpu.dataView.getUint16(26, true) + 1, true); + const x = cpu.dataView.getUint16(26, true); + cpu.writeData(x, cpu.data[(opcode & 0x1f0) >> 4]); + cpu.dataView.setUint16(26, x + 1, true); } /* STX, 1001 001r rrrr 1110 */ if ((opcode & 0xfe0f) === 0x920e) { const i = cpu.data[(opcode & 0x1f0) >> 4]; - cpu.dataView.setUint16(26, cpu.dataView.getUint16(26, true) - 1, true); - cpu.writeData(cpu.dataView.getUint16(26, true), i); + const x = cpu.dataView.getUint16(26, true) - 1; + cpu.dataView.setUint16(26, x, true); + cpu.writeData(x, i); cpu.cycles++; } |