Thread: Trying to follow C18 interrupt context code...
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Unread 20-12-2006, 22:34
dcbrown dcbrown is offline
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Re: Trying to follow C18 interrupt context code...
52E6 MOVF 0xfe6, F, ACCESS

This instruction, according to the PIC18F manual, should cause the FSR1L to be incremented twice - once upon the reading of the data pointed to by FSR1 through the POSTINC1 pseudo-register and once again upon writing to ram pointed to by FSR1 through POSTINC1.


If the instruction was the following, then FSR1 would only be accessed on the read with the results left in the W register. In this case the FSR1 would be only incremented once.

50E6 MOVF 0xfe6, W, ACCESS

This was the instruction I was expecting to see.

Bud
Last edited by dcbrown : 20-12-2006 at 22:51.