test(instruction): use assembly in tests

Refactored the tests to use AVR assembly instead of hardcoded
bytecode.
This change should make the tests much easier to read and maintain.

Before:
    loadProgram('659a');

Now:
    loadProgram('SBI 0x0c, 5');

1 files changed, 91 insertions, 89 deletions

diff --git a/src/cpu/instruction.spec.ts b/src/cpu/instruction.spec.ts
index 2c5244e..c3508e6 100644
--- a/src/cpu/instruction.spec.ts
+++ b/src/cpu/instruction.spec.ts
@@ -1,5 +1,6 @@
 import { CPU } from './cpu';
 import { avrInstruction } from './instruction';
+import { assemble } from '../utils/assembler';
 
 describe('avrInstruction', () => {
   let cpu: CPU;
@@ -8,15 +9,16 @@ describe('avrInstruction', () => {
     cpu = new CPU(new Uint16Array(0x8000));
   });
 
-  function loadProgram(bytes: string) {
-    const progBuf = cpu.progBytes;
-    for (let i = 0; i < bytes.length; i += 2) {
-      progBuf[i / 2] = parseInt(bytes.substr(i, 2), 16);
+  function loadProgram(...instructions: string[]) {
+    const { bytes, errors } = assemble(instructions.join('\n'));
+    if (errors.length) {
+      throw new Error('Assembly failed: ' + errors);
     }
+    cpu.progBytes.set(bytes, 0);
   }
 
   it('should execute `ADC r0, r1` instruction when carry is on', () => {
-    loadProgram('011c');
+    loadProgram('ADC r0, r1');
     cpu.data[0] = 10; // r0 <- 10
     cpu.data[1] = 20; // r1 <- 20
     cpu.data[95] = 0b00000001; // SREG <- -------C
@@ -28,7 +30,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `ADC r0, r1` instruction when carry is on and the result overflows', () => {
-    loadProgram('011c');
+    loadProgram('ADC r0, r1');
     cpu.data[0] = 10; // r0 <- 10
     cpu.data[1] = 245; // r1 <- 20
     cpu.data[95] = 0b00000001; // SREG <- -------C
@@ -40,7 +42,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `BCLR 2` instruction', () => {
-    loadProgram('a894');
+    loadProgram('BCLR 2');
     cpu.data[95] = 0xff; // SREG <- 0xff
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -49,7 +51,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `BLD r4, 7` instruction', () => {
-    loadProgram('47f8');
+    loadProgram('BLD r4, 7');
     cpu.data[4] = 0x15; // r <- 0x15
     cpu.data[95] = 0x40; // SREG <- 0x40
     avrInstruction(cpu);
@@ -60,7 +62,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `BRBC 0, +8` instruction when SREG.C is clear', () => {
-    loadProgram('20f4');
+    loadProgram('BRBC 0, +8');
     cpu.data[95] = 0b00001000; // SREG: V
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1 + 8 / 2);
@@ -68,7 +70,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `BRBC 0, +8` instruction when SREG.C is set', () => {
-    loadProgram('20f4');
+    loadProgram('BRBC 0, +8');
     cpu.data[95] = 0b00000001; // SREG: C
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -76,7 +78,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `BRBS 3, 92` instruction when SREG.V is set', () => {
-    loadProgram('73f1');
+    loadProgram('BRBS 3, 92');
     cpu.data[95] = 0b00001000; // SREG: V
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1 + 92 / 2);
@@ -84,7 +86,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `BRBS 3, -4` instruction when SREG.V is set', () => {
-    loadProgram('0000f3f3');
+    loadProgram('BRBS 3, -4');
     cpu.data[95] = 0b00001000; // SREG: V
     avrInstruction(cpu);
     avrInstruction(cpu);
@@ -93,7 +95,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `BRBS 3, -4` instruction when SREG.V is clear', () => {
-    loadProgram('f3f3');
+    loadProgram('BRBS 3, -4');
     cpu.data[95] = 0x0; // SREG <- 0x0
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -101,7 +103,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `CBI 0x0c, 5`', () => {
-    loadProgram('6598');
+    loadProgram('CBI 0x0c, 5');
     cpu.data[0x2c] = 0b11111111;
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -110,7 +112,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `CALL` instruction', () => {
-    loadProgram('0e945c00');
+    loadProgram('CALL 0xb8');
     cpu.data[94] = 0;
     cpu.data[93] = 150; // SP <- 50
     avrInstruction(cpu);
@@ -121,7 +123,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `CPC r27, r18` instruction', () => {
-    loadProgram('b207');
+    loadProgram('CPC r27, r18');
     cpu.data[18] = 0x1;
     cpu.data[27] = 0x1;
     avrInstruction(cpu);
@@ -131,7 +133,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `CPC r24, r1` instruction and set', () => {
-    loadProgram('8105');
+    loadProgram('CPC r24, r1');
     cpu.data[1] = 0; // r1 <- 0
     cpu.data[24] = 0; // r24 <- 0
     cpu.data[95] = 0b10000001; // SREG: I-------C
@@ -142,7 +144,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `CPI r26, 0x9` instruction', () => {
-    loadProgram('a930');
+    loadProgram('CPI r26, 0x9');
     cpu.data[26] = 0x8;
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -151,7 +153,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `CPSE r2, r3` when r2 != r3', () => {
-    loadProgram('2310');
+    loadProgram('CPSE r2, r3');
     cpu.data[2] = 10; // r2 <- 10
     cpu.data[3] = 11; // r3 <- 11
     avrInstruction(cpu);
@@ -160,7 +162,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `CPSE r2, r3` when r2 == r3', () => {
-    loadProgram('23101c92');
+    loadProgram('CPSE r2, r3');
     cpu.data[2] = 10; // r2 <- 10
     cpu.data[3] = 10; // r3 <- 10
     avrInstruction(cpu);
@@ -169,7 +171,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `CPSE r2, r3` when r2 == r3 and followed by 2-word instruction', () => {
-    loadProgram('23100e945c00');
+    loadProgram('CPSE r2, r3', 'CALL 8');
     cpu.data[2] = 10; // r2 <- 10
     cpu.data[3] = 10; // r3 <- 10
     avrInstruction(cpu);
@@ -178,7 +180,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `ICALL` instruction', () => {
-    loadProgram('0995');
+    loadProgram('ICALL');
     cpu.data[94] = 0;
     cpu.data[93] = 0x80;
     cpu.dataView.setUint16(30, 0x2020, true); // Z <- 0x2020
@@ -190,7 +192,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `IJMP` instruction', () => {
-    loadProgram('0994');
+    loadProgram('IJMP');
     cpu.dataView.setUint16(30, 0x1040, true); // Z <- 0x1040
     avrInstruction(cpu);
     expect(cpu.cycles).toEqual(2);
@@ -198,7 +200,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `IN r5, 0xb` instruction', () => {
-    loadProgram('5bb0');
+    loadProgram('IN r5, 0xb');
     cpu.data[0x2b] = 0xaf;
     avrInstruction(cpu);
     expect(cpu.cycles).toEqual(1);
@@ -207,7 +209,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `INC r5` instruction', () => {
-    loadProgram('5394');
+    loadProgram('INC r5');
     cpu.data[5] = 0x7f;
     avrInstruction(cpu);
     expect(cpu.data[5]).toEqual(0x80);
@@ -217,7 +219,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `INC r5` instruction when r5 == 0xff', () => {
-    loadProgram('5394');
+    loadProgram('INC r5');
     cpu.data[5] = 0xff;
     avrInstruction(cpu);
     expect(cpu.data[5]).toEqual(0);
@@ -227,14 +229,14 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `JMP 0xb8` instruction', () => {
-    loadProgram('0c945c00');
+    loadProgram('JMP 0xb8');
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(0x5c);
     expect(cpu.cycles).toEqual(3);
   });
 
-  it('should execute `LAC r19` instruction', () => {
-    loadProgram('3693');
+  it('should execute `LAC Z, r19` instruction', () => {
+    loadProgram('LAC Z, r19');
     cpu.data[19] = 0x02; // r19 <- 0x02
     cpu.dataView.setUint16(30, 0x100, true); // Z <- 0x100
     cpu.data[0x100] = 0x96;
@@ -246,8 +248,8 @@ describe('avrInstruction', () => {
     expect(cpu.data[0x100]).toEqual(0x94);
   });
 
-  it('should execute `LAS r17` instruction', () => {
-    loadProgram('1593');
+  it('should execute `LAS Z, r17` instruction', () => {
+    loadProgram('LAS Z, r17');
     cpu.data[17] = 0x11; // r17 <- 0x11
     cpu.data[30] = 0x80; // Z <- 0x80
     cpu.data[0x80] = 0x44;
@@ -259,8 +261,8 @@ describe('avrInstruction', () => {
     expect(cpu.data[0x80]).toEqual(0x55);
   });
 
-  it('should execute `LAT r0` instruction', () => {
-    loadProgram('0792');
+  it('should execute `LAT Z, r0` instruction', () => {
+    loadProgram('LAT Z, r0');
     cpu.data[0] = 0x33; // r0 <- 0x33
     cpu.data[30] = 0x80; // Z <- 0x80
     cpu.data[0x80] = 0x66;
@@ -273,7 +275,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LDI r28, 0xff` instruction', () => {
-    loadProgram('cfef');
+    loadProgram('LDI r28, 0xff');
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(0x1);
     expect(cpu.cycles).toEqual(1);
@@ -281,7 +283,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LDS r5, 0x150` instruction', () => {
-    loadProgram('50905001');
+    loadProgram('LDS r5, 0x150');
     cpu.data[0x150] = 0x7a;
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(0x2);
@@ -290,7 +292,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LD r1, X` instruction', () => {
-    loadProgram('1c90');
+    loadProgram('LD r1, X');
     cpu.data[0xc0] = 0x15;
     cpu.data[26] = 0xc0; // X <- 0xc0
     avrInstruction(cpu);
@@ -301,7 +303,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LD r17, X+` instruction', () => {
-    loadProgram('1d91');
+    loadProgram('LD r17, X+');
     cpu.data[0xc0] = 0x15;
     cpu.data[26] = 0xc0; // X <- 0xc0
     avrInstruction(cpu);
@@ -312,7 +314,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LD r1, -X` instruction', () => {
-    loadProgram('1e90');
+    loadProgram('LD r1, -X');
     cpu.data[0x98] = 0x22;
     cpu.data[26] = 0x99; // X <- 0x99
     avrInstruction(cpu);
@@ -323,7 +325,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LD r8, Y` instruction', () => {
-    loadProgram('8880');
+    loadProgram('LD r8, Y');
     cpu.data[0xc0] = 0x15;
     cpu.data[28] = 0xc0; // Y <- 0xc0
     avrInstruction(cpu);
@@ -334,7 +336,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LD r3, Y+` instruction', () => {
-    loadProgram('3990');
+    loadProgram('LD r3, Y+');
     cpu.data[0xc0] = 0x15;
     cpu.data[28] = 0xc0; // Y <- 0xc0
     avrInstruction(cpu);
@@ -345,7 +347,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LD r0, -Y` instruction', () => {
-    loadProgram('0a90');
+    loadProgram('LD r0, -Y');
     cpu.data[0x98] = 0x22;
     cpu.data[28] = 0x99; // Y <- 0x99
     avrInstruction(cpu);
@@ -356,7 +358,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LDD r4, Y+2` instruction', () => {
-    loadProgram('4a80');
+    loadProgram('LDD r4, Y+2');
     cpu.data[0x82] = 0x33;
     cpu.data[28] = 0x80; // Y <- 0x80
     avrInstruction(cpu);
@@ -367,7 +369,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LD r5, Z` instruction', () => {
-    loadProgram('5080');
+    loadProgram('LD r5, Z');
     cpu.data[0xcc] = 0xf5;
     cpu.data[30] = 0xcc; // Z <- 0xcc
     avrInstruction(cpu);
@@ -378,7 +380,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LD r7, Z+` instruction', () => {
-    loadProgram('7190');
+    loadProgram('LD r7, Z+');
     cpu.data[0xc0] = 0x25;
     cpu.data[30] = 0xc0; // Z <- 0xc0
     avrInstruction(cpu);
@@ -389,7 +391,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LD r0, -Z` instruction', () => {
-    loadProgram('0290');
+    loadProgram('LD r0, -Z');
     cpu.data[0x9e] = 0x66;
     cpu.data[30] = 0x9f; // Z <- 0x9f
     avrInstruction(cpu);
@@ -400,7 +402,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LDD r15, Z+31` instruction', () => {
-    loadProgram('f78c');
+    loadProgram('LDD r15, Z+31');
     cpu.data[0x9f] = 0x33;
     cpu.data[30] = 0x80; // Z <- 0x80
     avrInstruction(cpu);
@@ -411,7 +413,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LPM` instruction', () => {
-    loadProgram('c895');
+    loadProgram('LPM');
     cpu.progMem[0x40] = 0xa0;
     cpu.data[30] = 0x80; // Z <- 0x80
     avrInstruction(cpu);
@@ -421,8 +423,8 @@ describe('avrInstruction', () => {
     expect(cpu.data[30]).toEqual(0x80); // verify that Z was unchanged
   });
 
-  it('should execute `LPM r2` instruction', () => {
-    loadProgram('2490');
+  it('should execute `LPM r2, Z` instruction', () => {
+    loadProgram('LPM r2, Z');
     cpu.progMem[0x40] = 0xa0;
     cpu.data[30] = 0x80; // Z <- 0x80
     avrInstruction(cpu);
@@ -433,7 +435,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LPM r1, Z+` instruction', () => {
-    loadProgram('1590');
+    loadProgram('LPM r1, Z+');
     cpu.progMem[0x40] = 0xa0;
     cpu.data[30] = 0x80; // Z <- 0x80
     avrInstruction(cpu);
@@ -444,7 +446,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `LSR r7` instruction', () => {
-    loadProgram('7694');
+    loadProgram('LSR r7');
     cpu.data[7] = 0x45; // r7 <- 0x45
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -454,7 +456,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `MOV r7, r8` instruction', () => {
-    loadProgram('782c');
+    loadProgram('MOV r7, r8');
     cpu.data[8] = 0x45; // r7 <- 0x45
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -463,7 +465,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `MOVW r26, r22` instruction', () => {
-    loadProgram('db01');
+    loadProgram('MOVW r26, r22');
     cpu.data[22] = 0x45; // r22 <- 0x45
     cpu.data[23] = 0x9a; // r23 <- 0x9a
     avrInstruction(cpu);
@@ -474,7 +476,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `MUL r5, r6` instruction', () => {
-    loadProgram('569c');
+    loadProgram('MUL r5, r6');
     cpu.data[5] = 100; // r5 <- 55
     cpu.data[6] = 5; // r6 <- 5
     avrInstruction(cpu);
@@ -485,7 +487,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `MUL r5, r6` instruction and update carry flag when numbers are big', () => {
-    loadProgram('569c');
+    loadProgram('MUL r5, r6');
     cpu.data[5] = 200; // r5 <- 200
     cpu.data[6] = 200; // r6 <- 200
     avrInstruction(cpu);
@@ -496,7 +498,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `MUL r0, r1` and update the zero flag', () => {
-    loadProgram('019c');
+    loadProgram('MUL r0, r1');
     cpu.data[0] = 0; // r0 <- 0
     cpu.data[1] = 9; // r1 <- 9
     avrInstruction(cpu);
@@ -507,7 +509,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `MULS r18, r19` instruction', () => {
-    loadProgram('2302');
+    loadProgram('MULS r18, r19');
     cpu.data[18] = -5; // r18 <- -5
     cpu.data[19] = 100; // r19 <- 100
     avrInstruction(cpu);
@@ -518,7 +520,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `MULSU r16, r17` instruction', () => {
-    loadProgram('0103');
+    loadProgram('MULSU r16, r17');
     cpu.data[16] = -5; // r16 <- -5
     cpu.data[17] = 200; // r17 <- 200
     avrInstruction(cpu);
@@ -529,7 +531,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `NEG r20` instruction', () => {
-    loadProgram('4195');
+    loadProgram('NEG r20');
     cpu.data[20] = 0x56; // r20 <- 0x56
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -539,14 +541,14 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `NOP` instruction', () => {
-    loadProgram('0000');
+    loadProgram('NOP');
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
     expect(cpu.cycles).toEqual(1);
   });
 
   it('should execute `OUT 0x3f, r1` instruction', () => {
-    loadProgram('1fbe');
+    loadProgram('OUT 0x3f, r1');
     cpu.data[1] = 0x5a; // r1 <- 0x5a
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(0x1);
@@ -555,7 +557,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `POP r26` instruction', () => {
-    loadProgram('af91');
+    loadProgram('POP r26');
     cpu.data[94] = 0;
     cpu.data[93] = 0xff; // SP <- 0xff
     cpu.data[0x100] = 0x1a;
@@ -567,7 +569,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `PUSH r11` instruction', () => {
-    loadProgram('bf92');
+    loadProgram('PUSH r11');
     cpu.data[11] = 0x2a;
     cpu.data[94] = 0;
     cpu.data[93] = 0xff; // SP <- 0xff
@@ -579,7 +581,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `RCALL .+6` instruction', () => {
-    loadProgram('03d0');
+    loadProgram('RCALL 6');
     cpu.data[94] = 0;
     cpu.data[93] = 0x80; // SP <- 0x80
     avrInstruction(cpu);
@@ -590,7 +592,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `RCALL .-4` instruction', () => {
-    loadProgram('0000fedf');
+    loadProgram('NOP', 'RCALL -4');
     cpu.data[94] = 0;
     cpu.data[93] = 0x80; // SP <- 0x80
     avrInstruction(cpu);
@@ -602,7 +604,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `RET` instruction', () => {
-    loadProgram('0895');
+    loadProgram('RET');
     cpu.data[94] = 0;
     cpu.data[93] = 0x90; // SP <- 0x90
     cpu.data[0x92] = 16;
@@ -613,7 +615,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `RETI` instruction', () => {
-    loadProgram('1895');
+    loadProgram('RETI');
     cpu.data[94] = 0;
     cpu.data[93] = 0xc0; // SP <- 0xc0
     cpu.data[0xc2] = 200;
@@ -625,14 +627,14 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `RJMP 2` instruction', () => {
-    loadProgram('01c0');
+    loadProgram('RJMP 2');
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(2);
     expect(cpu.cycles).toEqual(2);
   });
 
   it('should execute `ROR r0` instruction', () => {
-    loadProgram('0794');
+    loadProgram('ROR r0');
     cpu.data[0] = 0x11; // r0 <- 0x11
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -642,7 +644,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `SBCI r23, 3`', () => {
-    loadProgram('7340');
+    loadProgram('SBCI r23, 3');
     cpu.data[23] = 3; // r23 <- 3
     cpu.data[95] = 0b10000001; // SREG <- I------C
     avrInstruction(cpu);
@@ -652,7 +654,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `SBI 0x0c, 5`', () => {
-    loadProgram('659a');
+    loadProgram('SBI 0x0c, 5');
     cpu.data[0x2c] = 0b00001111;
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -661,7 +663,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `SBIS 0x0c, 5` when bit is clear', () => {
-    loadProgram('659b1c92');
+    loadProgram('SBIS 0x0c, 5');
     cpu.data[0x2c] = 0b00001111;
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -669,7 +671,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `SBIS 0x0c, 5` when bit is set', () => {
-    loadProgram('659b1c92');
+    loadProgram('SBIS 0x0c, 5');
     cpu.data[0x2c] = 0b00101111;
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(2);
@@ -677,7 +679,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `SBIS 0x0c, 5` when bit is set and followed by 2-word instruction', () => {
-    loadProgram('659b0e945c00');
+    loadProgram('SBIS 0x0c, 5', 'CALL 0xb8');
     cpu.data[0x2c] = 0b00101111;
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(3);
@@ -685,7 +687,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `STS 0x151, r31` instruction', () => {
-    loadProgram('f0935101');
+    loadProgram('STS 0x151, r31');
     cpu.data[31] = 0x80; // r31 <- 0x80
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(2);
@@ -694,7 +696,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `ST X, r1` instruction', () => {
-    loadProgram('1c92');
+    loadProgram('ST X, r1');
     cpu.data[1] = 0x5a; // r1 <- 0x5a
     cpu.data[26] = 0x9a; // X <- 0x9a
     avrInstruction(cpu);
@@ -705,7 +707,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `ST X+, r1` instruction', () => {
-    loadProgram('1d92');
+    loadProgram('ST X+, r1');
     cpu.data[1] = 0x5a; // r1 <- 0x5a
     cpu.data[26] = 0x9a; // X <- 0x9a
     avrInstruction(cpu);
@@ -716,7 +718,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `ST -X, r17` instruction', () => {
-    loadProgram('1e93');
+    loadProgram('ST -X, r17');
     cpu.data[17] = 0x88; // r17 <- 0x88
     cpu.data[26] = 0x99; // X <- 0x99
     avrInstruction(cpu);
@@ -727,7 +729,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `ST Y, r2` instruction', () => {
-    loadProgram('2882');
+    loadProgram('ST Y, r2');
     cpu.data[2] = 0x5b; // r2 <- 0x5b
     cpu.data[28] = 0x9a; // Y <- 0x9a
     avrInstruction(cpu);
@@ -738,7 +740,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `ST Y+, r1` instruction', () => {
-    loadProgram('1992');
+    loadProgram('ST Y+, r1');
     cpu.data[1] = 0x5a; // r1 <- 0x5a
     cpu.data[28] = 0x9a; // Y <- 0x9a
     avrInstruction(cpu);
@@ -749,7 +751,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `ST -Y, r1` instruction', () => {
-    loadProgram('1a92');
+    loadProgram('ST -Y, r1');
     cpu.data[1] = 0x5a; // r1 <- 0x5a
     cpu.data[28] = 0x9a; // Y <- 0x9a
     avrInstruction(cpu);
@@ -760,7 +762,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `STD Y+17, r0` instruction', () => {
-    loadProgram('098a');
+    loadProgram('STD Y+17, r0');
     cpu.data[0] = 0xba; // r0 <- 0xba
     cpu.data[28] = 0x9a; // Y <- 0x9a
     avrInstruction(cpu);
@@ -771,7 +773,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `ST Z, r16` instruction', () => {
-    loadProgram('0083');
+    loadProgram('ST Z, r16');
     cpu.data[16] = 0xdf; // r2 <- 0xdf
     cpu.data[30] = 0x40; // Z <- 0x40
     avrInstruction(cpu);
@@ -782,7 +784,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `ST Z+, r0` instruction', () => {
-    loadProgram('0192');
+    loadProgram('ST Z+, r0');
     cpu.data[0] = 0x55; // r0 <- 0x55
     cpu.dataView.setUint16(30, 0x155, true); // Z <- 0x155
     avrInstruction(cpu);
@@ -793,7 +795,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `ST -Z, r16` instruction', () => {
-    loadProgram('0293');
+    loadProgram('ST -Z, r16');
     cpu.data[16] = 0x5a; // r16 <- 0x5a
     cpu.data[30] = 0xff; // Z <- 0xff
     avrInstruction(cpu);
@@ -804,7 +806,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `STD Z+1, r0` instruction', () => {
-    loadProgram('0182');
+    loadProgram('STD Z+1, r0');
     cpu.data[0] = 0xcc; // r0 <- 0xcc
     cpu.data[30] = 0x50; // Z <- 0x50
     avrInstruction(cpu);
@@ -815,7 +817,7 @@ describe('avrInstruction', () => {
   });
 
   it('should execute `SWAP r1` instruction', () => {
-    loadProgram('1294');
+    loadProgram('SWAP r1');
     cpu.data[1] = 0xa5; // r1 <- 0xa5
     avrInstruction(cpu);
     expect(cpu.pc).toEqual(1);
@@ -823,8 +825,8 @@ describe('avrInstruction', () => {
     expect(cpu.data[1]).toEqual(0x5a); // r1
   });
 
-  it('should execute `XCH r21` instruction', () => {
-    loadProgram('5493');
+  it('should execute `XCH Z, r21` instruction', () => {
+    loadProgram('XCH Z, r21');
     cpu.data[21] = 0xa1; // r21 <- 0xa1
     cpu.data[30] = 0x50; // Z <- 0x50
     cpu.data[0x50] = 0xb9;