Hello. I have a problem programming in assebly at 6502 processor. I have a project to give to my lecturer on Tuesday 28 May and I want your help.
Here is the deal:
I have a 2 dimensional table (8 bit) and I want to calculate the sum of it's diagonal and the sums of up and down triangular place. For example:

12 52 61
43 06 12
87 01 76

I want to calculate the sum of No -> 12+06+76
and the sum of the No -> 52+61+12
and also the No -> 43+87+01

I would be gratefull if anyone can help me to this. THANK YOU!!!

Please post your questions only once in the forum. Your duplicate question was deleted.

If you'd like to post your code and ask a specific question I'm sure there are people here who would like to help you.

Regards,
Mike

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- Mike Naberezny (mike@naberezny.com) http://6502.org

I'd use indirect addressing, I've done stuff sorta similar to that before. That way you have 2 axes, the Y register and the address in memory.

I'm sure there's other ways to handle it.

The simplest way would be to put the matrix at a fixed memory location (say somewhere on zero page) and access its values as offsets from the base location, for example

If the values are guaranteed never to add up to a value over 255 then a sequence of CLC / LDA first cell / ADC second cell /ADC third cell will give you the sum for the diagonal or upper/lower triangle. If the sum can be bigger than 255 then keep the low big in the accumulator and use either X or Y to hold the high bytes (hint: after each ADC check for a carry and increment X/Y if needed - remember to clear the carry before the next ADC).

_________________
Andrew Jacobs
6502 & PIC Stuff - http://www.obelisk.me.uk/
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