0xrsydn/gameboy-rust
1
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

fix(timers): retain shared free-running prescaler phase

Browse source
This commit is contained in:
0xrsydn 2026-10-06 22:04:59 +07:00
commit 27806ccf9e
13 changed files with 459 additions and 32 deletions
Download patch file Download diff file Expand all files Collapse all files

11
crates/gba-core/tests/timers.rs
View file

@ -100,7 +100,7 @@ fn all_prescalers_retain_fractional_cycles_between_advances() {
}
#[test]
fn clock_source_changes_and_restart_reset_provisional_phase() {
fn clock_source_changes_and_restart_keep_the_shared_phase() {
let mut bus = memory();
bus.write32(TIMER_BASE, 0x0081_0000).unwrap(); // /64
bus.advance_cycles(63);
@ -108,16 +108,17 @@ fn clock_source_changes_and_restart_reset_provisional_phase() {
bus.advance_cycles(1);
assert_eq!(bus.read16(TIMER_BASE).unwrap(), 1);
bus.advance_cycles(63);
bus.write16(TIMER_BASE + 2, 0x82).unwrap(); // /256 resets phase
bus.advance_cycles(255);
bus.write16(TIMER_BASE + 2, 0x82).unwrap(); // t=127: next shared /256 edge is t=256.
bus.advance_cycles(128);
assert_eq!(bus.read16(TIMER_BASE).unwrap(), 1);
bus.advance_cycles(1);
assert_eq!(bus.read16(TIMER_BASE).unwrap(), 2);
bus.write16(TIMER_BASE + 2, 0).unwrap();
bus.advance_cycles(255);
bus.advance_cycles(255); // t=511; disabled time still advances the divider.
bus.write16(TIMER_BASE + 2, 0x82).unwrap();
bus.advance_cycles(255);
assert_eq!(bus.read16(TIMER_BASE).unwrap(), 0);
bus.advance_cycles(1);
assert_eq!(bus.read16(TIMER_BASE).unwrap(), 1);
}
#[test]