feat: LDY/LDZ/LDDY/LDDZ instructions + tests

2 files changed, 142 insertions, 22 deletions

diff --git a/src/instruction.spec.ts b/src/instruction.spec.ts
index f804a85..29c9a49 100644
--- a/src/instruction.spec.ts
+++ b/src/instruction.spec.ts
@@ -72,11 +72,11 @@ describe('avrInstruction', () => {
   it('should execute `LD r17, X+` instruction', () => {
     loadProgram('1d91');
     cpu.data[0xc0] = 0x15;
-    cpu.data[26] = 0xc0; // X <- 0x9a
+    cpu.data[26] = 0xc0; // X <- 0xc0
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
     expect(cpu.cycles).toEqual(2);
-    expect(cpu.data[0xc0]).toEqual(0x15);
+    expect(cpu.data[17]).toEqual(0x15);
     expect(cpu.data[26]).toEqual(0xc1); // verify that X was incremented
   });
 
@@ -91,6 +91,94 @@ describe('avrInstruction', () => {
     expect(cpu.data[26]).toEqual(0x98); // verify that X was decremented
   });
 
+  it('should execute `LD r8, Y` instruction', () => {
+    loadProgram('8880');
+    cpu.data[0xc0] = 0x15;
+    cpu.data[28] = 0xc0; // Y <- 0xc0
+    avrInstruction(cpu);
+    expect(cpu.pc).toEqual(1);
+    expect(cpu.cycles).toEqual(1);
+    expect(cpu.data[8]).toEqual(0x15);
+    expect(cpu.data[28]).toEqual(0xc0); // verify that Y was unchanged
+  });
+
+  it('should execute `LD r3, Y+` instruction', () => {
+    loadProgram('3990');
+    cpu.data[0xc0] = 0x15;
+    cpu.data[28] = 0xc0; // Y <- 0xc0
+    avrInstruction(cpu);
+    expect(cpu.pc).toEqual(1);
+    expect(cpu.cycles).toEqual(2);
+    expect(cpu.data[3]).toEqual(0x15);
+    expect(cpu.data[28]).toEqual(0xc1); // verify that Y was incremented
+  });
+
+  it('should execute `LD r0, -Y` instruction', () => {
+    loadProgram('0a90');
+    cpu.data[0x98] = 0x22;
+    cpu.data[28] = 0x99; // Y <- 0x99
+    avrInstruction(cpu);
+    expect(cpu.pc).toEqual(1);
+    expect(cpu.cycles).toEqual(3);
+    expect(cpu.data[0]).toEqual(0x22);
+    expect(cpu.data[28]).toEqual(0x98); // verify that Y was decremented
+  });
+
+  it('should execute `LDD r4, Y+2` instruction', () => {
+    loadProgram('4a80');
+    cpu.data[0x82] = 0x33;
+    cpu.data[28] = 0x80; // Y <- 0x80
+    avrInstruction(cpu);
+    expect(cpu.pc).toEqual(1);
+    expect(cpu.cycles).toEqual(3);
+    expect(cpu.data[4]).toEqual(0x33);
+    expect(cpu.data[28]).toEqual(0x80); // verify that Y was unchanged
+  });
+
+  it('should execute `LD r5, Z` instruction', () => {
+    loadProgram('5080');
+    cpu.data[0xcc] = 0xf5;
+    cpu.data[30] = 0xcc; // Z <- 0xcc
+    avrInstruction(cpu);
+    expect(cpu.pc).toEqual(1);
+    expect(cpu.cycles).toEqual(1);
+    expect(cpu.data[5]).toEqual(0xf5);
+    expect(cpu.data[30]).toEqual(0xcc); // verify that Z was unchanged
+  });
+
+  it('should execute `LD r7, Z+` instruction', () => {
+    loadProgram('7190');
+    cpu.data[0xc0] = 0x25;
+    cpu.data[30] = 0xc0; // Z <- 0xc0
+    avrInstruction(cpu);
+    expect(cpu.pc).toEqual(1);
+    expect(cpu.cycles).toEqual(2);
+    expect(cpu.data[7]).toEqual(0x25);
+    expect(cpu.data[30]).toEqual(0xc1); // verify that Y was incremented
+  });
+
+  it('should execute `LD r0, -Z` instruction', () => {
+    loadProgram('0290');
+    cpu.data[0x9e] = 0x66;
+    cpu.data[30] = 0x9f; // Z <- 0x9f
+    avrInstruction(cpu);
+    expect(cpu.pc).toEqual(1);
+    expect(cpu.cycles).toEqual(3);
+    expect(cpu.data[0]).toEqual(0x66);
+    expect(cpu.data[30]).toEqual(0x9e); // verify that Y was decremented
+  });
+
+  it('should execute `LDD r15, Z+31` instruction', () => {
+    loadProgram('f78c');
+    cpu.data[0x9f] = 0x33;
+    cpu.data[30] = 0x80; // Z <- 0x80
+    avrInstruction(cpu);
+    expect(cpu.pc).toEqual(1);
+    expect(cpu.cycles).toEqual(3);
+    expect(cpu.data[15]).toEqual(0x33);
+    expect(cpu.data[30]).toEqual(0x80); // verify that Z was unchanged
+  });
+
   it('should execute `RJMP 2` instruction', () => {
     loadProgram('01c0');
     avrInstruction(cpu);
@@ -137,14 +225,14 @@ describe('avrInstruction', () => {
     cpu.data[28] = 0x9a; // Y <- 0x9a
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
-    expect(cpu.cycles).toEqual(2);
+    expect(cpu.cycles).toEqual(1);
     expect(cpu.data[0x9a]).toEqual(0x5b);
     expect(cpu.data[28]).toEqual(0x9a); // verify that Y was unchanged
   });
 
   it('should execute `ST Y+, r1` instruction', () => {
     loadProgram('1992');
-    cpu.data[1] = 0x5a; // r1 <- 5a
+    cpu.data[1] = 0x5a; // r1 <- 0x5a
     cpu.data[28] = 0x9a; // Y <- 0x9a
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -155,7 +243,7 @@ describe('avrInstruction', () => {
 
   it('should execute `ST -Y, r1` instruction', () => {
     loadProgram('1a92');
-    cpu.data[1] = 0x5a; // r1 <- 5a
+    cpu.data[1] = 0x5a; // r1 <- 0x5a
     cpu.data[28] = 0x9a; // Y <- 0x9a
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -166,7 +254,7 @@ describe('avrInstruction', () => {
 
   it('should execute `STD Y+17, r0` instruction', () => {
     loadProgram('098a');
-    cpu.data[0] = 0xba; // r0 <- ba
+    cpu.data[0] = 0xba; // r0 <- 0xba
     cpu.data[28] = 0x9a; // Y <- 0x9a
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -181,7 +269,7 @@ describe('avrInstruction', () => {
     cpu.data[30] = 0x40; // Z <- 0x40
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
-    expect(cpu.cycles).toEqual(2);
+    expect(cpu.cycles).toEqual(1);
     expect(cpu.data[0x40]).toEqual(0xdf);
     expect(cpu.data[30]).toEqual(0x40); // verify that Z was unchanged
   });
diff --git a/src/instruction.ts b/src/instruction.ts
index 6eafb19..7eaa105 100644
--- a/src/instruction.ts
+++ b/src/instruction.ts
@@ -210,7 +210,7 @@ export function avrInstruction(cpu: ICPU) {
   /* LDX, 1001 000d dddd 1101 */
   if ((opcode & 0xfe0f) === 0x900d) {
     const x = cpu.dataView.getUint16(26, true);
-    cpu.data[(opcode & 0x1f0) >> 4] = x;
+    cpu.data[(opcode & 0x1f0) >> 4] = cpu.readData(x);
     cpu.dataView.setUint16(26, x + 1, true);
     cpu.cycles++;
   }
@@ -225,42 +225,68 @@ export function avrInstruction(cpu: ICPU) {
 
   /* LDY, 1000 000d dddd 1000 */
   if ((opcode & 0xfe0f) === 0x8008) {
-    /* not implemented */
+    cpu.data[(opcode & 0x1f0) >> 4] = cpu.readData(cpu.dataView.getUint16(28, true));
   }
 
   /* LDY, 1001 000d dddd 1001 */
   if ((opcode & 0xfe0f) === 0x9009) {
-    /* not implemented */
+    const y = cpu.dataView.getUint16(28, true);
+    cpu.data[(opcode & 0x1f0) >> 4] = cpu.readData(y);
+    cpu.dataView.setUint16(28, y + 1, true);
+    cpu.cycles++;
   }
 
   /* LDY, 1001 000d dddd 1010 */
   if ((opcode & 0xfe0f) === 0x900a) {
-    /* not implemented */
+    const y = cpu.dataView.getUint16(28, true) - 1;
+    cpu.dataView.setUint16(28, y, true);
+    cpu.data[(opcode & 0x1f0) >> 4] = cpu.readData(y);
+    cpu.cycles += 2;
   }
 
-  /* LDY, 10q0 qq0d dddd 1qqq */
-  if ((opcode & 0xd208) === 0x8008) {
-    /* not implemented */
+  /* LDDY, 10q0 qq0d dddd 1qqq */
+  if (
+    (opcode & 0xd208) === 0x8008 &&
+    (opcode & 7) | ((opcode & 0xc00) >> 7) | ((opcode & 0x2000) >> 8)
+  ) {
+    cpu.data[(opcode & 0x1f0) >> 4] = cpu.readData(
+      cpu.dataView.getUint16(28, true) +
+        ((opcode & 7) | ((opcode & 0xc00) >> 7) | ((opcode & 0x2000) >> 8))
+    );
+    cpu.cycles += 2;
   }
 
   /* LDZ, 1000 000d dddd 0000 */
   if ((opcode & 0xfe0f) === 0x8000) {
-    /* not implemented */
+    cpu.data[(opcode & 0x1f0) >> 4] = cpu.readData(cpu.dataView.getUint16(30, true));
   }
 
   /* LDZ, 1001 000d dddd 0001 */
   if ((opcode & 0xfe0f) === 0x9001) {
-    /* not implemented */
+    const z = cpu.dataView.getUint16(30, true);
+    cpu.data[(opcode & 0x1f0) >> 4] = cpu.readData(z);
+    cpu.dataView.setUint16(30, z + 1, true);
+    cpu.cycles++;
   }
 
   /* LDZ, 1001 000d dddd 0010 */
   if ((opcode & 0xfe0f) === 0x9002) {
-    /* not implemented */
+    const z = cpu.dataView.getUint16(30, true) - 1;
+    cpu.dataView.setUint16(30, z, true);
+    cpu.data[(opcode & 0x1f0) >> 4] = cpu.readData(z);
+    cpu.cycles += 2;
   }
 
-  /* LDZ, 10q0 qq0d dddd 0qqq */
-  if ((opcode & 0xd208) === 0x8000) {
-    /* not implemented */
+  /* LDDZ, 10q0 qq0d dddd 0qqq */
+  if (
+    (opcode & 0xd208) === 0x8000 &&
+    (opcode & 7) | ((opcode & 0xc00) >> 7) | ((opcode & 0x2000) >> 8)
+  ) {
+    cpu.data[(opcode & 0x1f0) >> 4] = cpu.readData(
+      cpu.dataView.getUint16(30, true) +
+        ((opcode & 7) | ((opcode & 0xc00) >> 7) | ((opcode & 0x2000) >> 8))
+    );
+    cpu.cycles += 2;
   }
 
   /* LPM, 1001 0101 1100 1000 */
@@ -473,7 +499,10 @@ export function avrInstruction(cpu: ICPU) {
   }
 
   /* STDY, 10q0 qq1r rrrr 1qqq */
-  if ((opcode & 0xd208) === 0x8208) {
+  if (
+    (opcode & 0xd208) === 0x8208 &&
+    (opcode & 7) | ((opcode & 0xc00) >> 7) | ((opcode & 0x2000) >> 8)
+  ) {
     cpu.writeData(
       cpu.dataView.getUint16(28, true) +
         ((opcode & 7) | ((opcode & 0xc00) >> 7) | ((opcode & 0x2000) >> 8)),
@@ -504,7 +533,10 @@ export function avrInstruction(cpu: ICPU) {
   }
 
   /* STDZ, 10q0 qq1r rrrr 0qqq */
-  if ((opcode & 0xd208) === 0x8200) {
+  if (
+    (opcode & 0xd208) === 0x8200 &&
+    (opcode & 7) | ((opcode & 0xc00) >> 7) | ((opcode & 0x2000) >> 8)
+  ) {
     cpu.writeData(
       cpu.dataView.getUint16(30, true) +
         ((opcode & 7) | ((opcode & 0xc00) >> 7) | ((opcode & 0x2000) >> 8)),