Re: [cc65] c64 question

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From: MagerValp (MagerValp_at_cling.gu.se)
Date: 2001-03-07 23:25:40 

>>>>> "AN" == Arvid Norberg <c99ang_at_cs.umu.se> writes:

AN> What happens when the 6502 gets an interrupt? I've always imagined
AN> that the folowing steps are performed by the CPU: 1. CPU registers
AN> were pushed onto the stack (a, x, y, pc).

Nope, only the PC and the status register (P) is pushed on the stack.
You have to push a, x, and y manually.

AN> 2. execution jumped to the interrupt handler

Yup.

AN> 3. when rti is reached, the resgisters are popped back and
AN> execution continues where it was interrupted.

Have to pop back a, x, and y manually.

-- 
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