I read a few documents and was trying to understand what happens to PC and PSW during interrupt, and it seems like there are contradictions in the documents:
On p.6, it says
"...when the interrupt fires the CPU takes the interrupt and starts by saving the current processing context. These steps are automatically done by the CPU.- First, the Program Counter and Program Status Word are pushed onto the stack.- The stack pointer is switched from the User Stack Pointer to the Interrupt Stack Pointer by clearingthe U bit in the PSW."
It seems like implying PC and PSW are pushed onto User Stack, then stack pointer is switched to Interrupt Stack
On p.258, Figure 5.2, it shows:
for exception other than the fast interrupt
- PC->Preserved on the stack (ISP)
- PSW->Preserved on the stack (ISP)
So what is going on here?
In reply to FrankL:
In reply to swoo.quek: