Implement and test remaining instructions

This commit is contained in:
n loewen 2023-07-26 12:09:11 +01:00
parent a17b7f4ba9
commit 10ada984e6
1 changed files with 156 additions and 12 deletions

View File

@ -1,3 +1,8 @@
// NOTES:
//
// - instructions are two bytes long:
// one byte for the opcode, one for the argument
// STATE
const CPU = {
@ -23,30 +28,114 @@ const Instructions = {
store_lit: (lit) => {
console.log('STO lit#');
CPU.memory[lit] = CPU.acc;
CPU.memory[lit] = CPU.Acc;
logTableTitled(CPU.memory, 'Current memory');
CPU.IP = CPU.IP += 2;
},
store_addr: (addr) => {
console.log('STO addr');
CPU.memory[CPU.memory[addr]] = CPU.acc;
CPU.memory[CPU.memory[addr]] = CPU.Acc;
logTableTitled(CPU.memory, 'Memory');
CPU.IP = CPU.IP += 2;
},
load_lit: (lit) => {
console.log('LDA lit#');
CPU.acc = lit;
CPU.Acc = lit;
CPU.IP = CPU.IP += 2;
},
load_addr: (addr) => {
console.log('LDA addr');
console.log('mem at addr: ', CPU.memory[addr]);
CPU.acc = CPU.memory[addr];
CPU.Acc = CPU.memory[addr];
CPU.IP = CPU.IP += 2;
},
add_lit: (lit) => {
console.log("ADD lit");
let sum = CPU.Acc + lit;
if (sum > 15) {
CPU.CF = 1;
CPU.Acc = (sum % 15) - 1;
} else {
CPU.CF = 0;
CPU.Acc = sum;
}
CPU.IP = CPU.IP += 2;
},
add_addr: (addr) => {
console.log("ADD addr");
let sum = CPU.Acc + CPU.memory[addr];
if (sum > 15) {
CPU.CF = 1;
CPU.Acc = (sum % 15) - 1;
} else {
CPU.CF = 0;
CPU.Acc = sum;
}
CPU.IP = CPU.IP += 2;
},
sub_lit: (lit) => { // TODO: carry flag
console.log("SUB lit");
CPU.Acc = CPU.Acc - lit;
CPU.IP = CPU.IP += 2;
},
sub_addr: (addr) => { // TODO: carry flag
console.log("SUB addr");
CPU.Acc = CPU.Acc - CPU.memory[addr];
CPU.IP = CPU.IP += 2;
},
hop_lit: (lit) => {
console.log("HOP lit");
console.log(` ↳ Memory at IP+2 and +3: ${CPU.memory[CPU.IP+2]}, ${CPU.memory[CPU.IP+3]}`);
if (CPU.Acc === lit) {
CPU.IP += 4;
} else {
CPU.IP += 2;
}
},
hop_addr: (addr) => {
console.log("HOP addr");
if (CPU.Acc === CPU.memory[addr]) {
CPU.IP += 4;
} else {
CPU.IP += 2;
}
},
jump_lit: (lit) => {
console.log("JMP lit");
CPU.IP = lit;
},
jump_addr: (addr) => {
console.log("JMP addr");
CPU.IP = CPU.memory[addr];
},
carry_clear: () => {
console.log("CFC");
CPU.CF = 0;
CPU.IP += 2;
},
carry_hop: () => {
console.log("CHP");
console.log(` ↳ Memory at IP+2 and +3: ${CPU.memory[CPU.IP+2]}, ${CPU.memory[CPU.IP+3]}`);
console.table(CPU.memory);
if (CPU.CF != 0) {
CPU.IP += 4;
} else {
CPU.IP += 2;
}
},
}
const instructionLookupTable = {
@ -55,6 +144,16 @@ const instructionLookupTable = {
2: (arg) => Instructions.store_addr(arg),
3: (arg) => Instructions.load_lit(arg),
4: (arg) => Instructions.load_addr(arg),
5: (arg) => Instructions.add_lit(arg),
6: (arg) => Instructions.add_addr(arg),
7: (arg) => Instructions.sub_lit(arg),
8: (arg) => Instructions.sub_addr(arg),
9: (arg) => Instructions.hop_lit(arg),
10: (arg) => Instructions.hop_addr(arg),
11: (arg) => Instructions.jump_lit(arg),
12: (arg) => Instructions.jump_addr(arg),
13: (arg) => Instructions.carry_clear(arg),
14: (arg) => Instructions.carry_hop(arg),
};
function stepCPU() {
@ -94,7 +193,7 @@ function runCPU() {
function logCPUState() {
console.log();
console.group('CPU state');
console.log( `Acc: ${CPU.acc} IP: ${CPU.IP} CF: ${CPU.CF}  ${CPU.running ? "running" : "halted" }` );
console.log( `Acc: ${CPU.Acc} IP: ${CPU.IP} CF: ${CPU.CF}  ${CPU.running ? "running" : "halted" }` );
console.log();
console.groupEnd('CPU state');
};
@ -116,15 +215,60 @@ logTableTitled = (memory, tableTitle) => {
// RUN IT !
const test_lda_sto = new Uint8Array([
3, 17, // LDA lit ... acc = 17
1, 14, // STO lit ... @14 = acc = 17
3, 16, // LDA lit ... acc = 16
1, 15, // STO lit ... @15 = acc = 16
2, 15, // STO addr ... @[@15] = acc = 16 ... mem[mem[addr]] <- Acc
4, 0, // LDA addr ... acc = @00 = 03
3, 17, // LDA lit ... Acc = 17
1, 14, // STO lit ... @14 = Acc = 17
3, 16, // LDA lit ... Acc = 16
1, 15, // STO lit ... @15 = Acc = 16
2, 15, // STO addr ... @[@15] = Acc = 16 ... mem[mem[addr]] <- Acc
4, 0, // LDA addr ... Acc = @00 = 03
0, 0, // END
0, 0, // DATA
]);
CPU.loadMemory(test_lda_sto);
let test_add_sub_nocarry = new Uint8Array([
5, 6, // ADD lit ... acc = 6
7, 1, // SUB lit ... acc = 5
1, 15, // STO lit ... mem[15] = 5
6, 15, // ADD addr ... acc = 10
8, 15, // SUB addr ... acc = 5
0, 0, // END
0, 0,
0, 0,
]);
let test_hop = new Uint8Array([
5, 8, // ADD lit ... acc = 8
9, 8, // HOP lit ... hop over next op if acc = 8
0, 0, // END ... (hopped over)
7, 8, // SUB lit ... acc = 0
0, 0
]);
let test_jmp = new Uint8Array([
11, 8, // 0 ... JMP lit
0, 0, // 2 ... END ... JMP'd over
0, 0, // 4
0, 0, // 6
5, 8, // 8 ... ADD lit ... acc = 8
0, 0, // 10 ... END
]);
const test_chp = new Uint8Array([
5, 8, // ADD lit ... Acc = 8
14, 0, // CHP ... shouldn't hop (CF = 0)
5, 1, // ADD lit ... Acc = 9
5, 8, // ADD lit ... Acc = 1 and CF = 1
14, 0, // CHP ... hop! (CF = 1)
0, 0, // END
7, 1, // SUB lit ... Acc = 0
13, 0, // CFC ... CF = 0
0, 0, // END
]);
//CPU.loadMemory(test_lda_sto);
//CPU.loadMemory(test_add_sub_nocarry);
//CPU.loadMemory(test_hop);
CPU.loadMemory(test_jmp);
//CPU.loadMemory(test_chp);
runCPU();