Posted By
 Csabo on 2014-08-02 10:12:48
| Re: Some programming help. Crash on CHROUT, maybe?
To acknowledge the IRQ, you must both read and write to $FF09. The most common way is to do LDA $FF09 / STA $FF09 (the value itself doesn't matter), or with one instruction as INC $FF09 (or equivalent). I think that might be the issue.
Otherwise, you should probably post the full code, or at least a working partial code which you've seen crash. |