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added the last set of instructions.

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This commit is contained in:
Jason Hilder
2026-05-27 07:16:39 +02:00
parent 6a4ed63138
commit 3876eba050
1 changed files with 70 additions and 8 deletions
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src/machine/cpu.odin
+70 -8
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@@ -1,6 +1,7 @@
package machine
import "core:log"
import "core:math/rand"
import "base:intrinsics"
// CPU.odin -> instructions, fetch, decode, execute, run loop
@@ -51,10 +52,22 @@ cycle :: proc(s: ^System) {
case 0x9: op_skip_reg_condition(s, vx_idx, vy_idx, false)
case 0xA: op_set(s, nnn)
case 0xB: op_jp_offset(s, nnn)
case 0xC: op_rnd(s, vx_idx, kk)
case 0xD: op_draw(s, vx_idx, vy_idx, last_nibble)
case 0xE: {
switch kk {
case 0x9E: op_skip_on_keypress(s, vx_idx)
case 0xA1: op_skip_on_nokeypress(s, vx_idx)
}
}
case 0xF: {
switch kk {
case 0x07: op_ld_dt(s, vx_idx)
case 0x0A: op_get_key(s, vx_idx)
case 0x15: op_set_dt(s, vx_idx)
case 0x18: op_set_st(s, vx_idx)
case 0x1E: op_add_i(s, vx_idx)
case 0x29: op_set_i(s, vx_idx)
case 0x33: op_split_i(s, vx_idx)
case 0x55: op_mem_set(s, vx_idx)
case 0x65: op_mem_get(s, vx_idx)
@@ -194,7 +207,11 @@ op_jp_offset :: proc(s: ^System, nnn: u16) {
s.pc += u16(s.v[0])
}
// Cxkk - RND Vx, byte : @TODO!
// Cxkk - RND Vx, byte
op_rnd :: proc(s: ^System, vx_idx: u16, kk: u8) {
rand_int := u8(rand.int_max(256))
s.v[vx_idx] = (rand_int & kk)
}
// Dxyn - DRW Vx, Vy, nibble
op_draw :: proc(s: ^System, vx_idx, vy_idx, n: u16) {
@@ -233,12 +250,54 @@ op_draw :: proc(s: ^System, vx_idx, vy_idx, n: u16) {
}
}
// Ex9E - SKP Vx : @TODO
// ExA1 - SKNP Vx : @TODO
// Fx07 - LD Vx, DT : @TODO
// Fx0A - LD Vx, K : @TODO
// Fx15 - LD DT, Vx : @TODO
// Fx18 - LD ST, Vx : @TODO
// Ex9E - SKP Vx
op_skip_on_keypress :: proc(s: ^System, vx_idx: u16) {
reg_value := s.v[vx_idx]
if s.keypad[reg_value] {
s.pc += 2
}
}
// ExA1 - SKNP Vx
op_skip_on_nokeypress :: proc(s: ^System, vx_idx: u16) {
reg_value := s.v[vx_idx]
if !s.keypad[reg_value] {
s.pc += 2
}
}
// Fx07 - LD Vx, DT
op_ld_dt :: proc(s: ^System, vx_idx: u16) {
s.v[vx_idx] = s.delay_timer
}
// Fx0A - LD Vx, K
op_get_key :: proc(s: ^System, vx_idx: u16) {
for val, kp_idx in s.keypad {
if val == true {
s.v[vx_idx] = u8(kp_idx)
// return here so it does not decrement
return
}
}
// if loop does not return decrement go into loop
s.pc -= 2
}
// Fx15 - LD DT, Vx
op_set_dt :: proc(s: ^System, vx_idx: u16) {
// set delay timer to value of x register
s.delay_timer = s.v[vx_idx]
}
// Fx18 - LD ST, Vx
op_set_st :: proc(s: ^System, vx_idx: u16) {
// set sound timer to value of x register
s.sound_timer = s.v[vx_idx]
}
// Fx1E - ADD I, Vx
op_add_i :: proc(s: ^System, vx_idx: u16) {
@@ -246,7 +305,10 @@ op_add_i :: proc(s: ^System, vx_idx: u16) {
s.v[0xF] = u8(1) if s.i > 0xFFF else u8(0)
}
// Fx29 - LD F, Vx : @TODO
// Fx29 - LD F, Vx
op_set_i :: proc(s: ^System, vx_idx: u16) {
s.i = u16(s.v[vx_idx]) * 5
}
// Fx33 - LD B, Vx
op_split_i :: proc(s: ^System, vx_idx: u16) {