IRQ Flag
From SnesLab
The IRQ Flag lives at bit 7 of TIMEUP (4211h).
IRQ Handlers should read this flag (which will cause it to automatically be cleared) otherwise the IRQ will fire again immediately after RTI.
The IRQ Flag lives at bit 7 of TIMEUP (4211h).
IRQ Handlers should read this flag (which will cause it to automatically be cleared) otherwise the IRQ will fire again immediately after RTI.