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don't overshoot the stack pointer! (pla and plp)

This commit is contained in:
Sam M W 2023-04-15 21:37:47 +01:00
parent 62424070a1
commit 26a2f51bc6
1 changed files with 2 additions and 2 deletions
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4
src/cpu.rs
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@ -433,13 +433,13 @@ impl<M: Bus> CPU<M> {
(Instruction::PLA, OpInput::UseImplied) => {
// Pull accumulator
self.pull_from_stack();
let val: u8 = self.pull_from_stack();
let val: u8 = self.fetch_from_stack();
self.registers.accumulator = val as i8;
}
(Instruction::PLP, OpInput::UseImplied) => {
// Pull status
self.pull_from_stack();
let val: u8 = self.pull_from_stack();
let val: u8 = self.fetch_from_stack();
// The `truncate` here won't do anything because we have a
// constant for the single unused flags bit. This probably
// corresponds to the behavior of the 6502...? FIXME: verify