Brilliant - thanks for the responses and help - lots to consider.

Hi,

I'm hoping to get some advise on the 6502 BIT instruction, as I can't seem to get it to do what I need.

So I understand that the instruction can be used to check if some bits are set (or not set) and it sets the zero flag accordingly.

I would like to check if bits 6 and 7 of a value stored in ...

Perfect! Thanks for your responses.

(its a 6502 I'm programming for... Also a BBC Micro which uses & for hex...)

Cheers.

Welcome.

There's (ZP,X) addressing, and there's (ZP),Y addressing, but no (ZP),X addressing. The 65c02 also has (ZP) addressing (with no indexing), so you don't need X or Y for this.

Thanks for your response, I found this explanation too:

INDIRECT INDEXED ADDRESSING - In indirect indexed ...

Hi,

Newbie question here!

So I want to store a value at memory location $5940.

I have another routine which calculates this memory location and it stores it in zero page as this

Location $70 = $40
Location $71 = $59

So I thought I could indirectly store to this location using:

LDA value to be ...