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Consider the following instructions: lda firstVar cmp secondVar b?? somewhereElse The cmp instruction sets up the flags such that the following instructions (which replace b?? above) do the following: For bcc (branch if carry clear): Jump if the value at address firstVar is less than the value at s...

tokumaru wrote:Sounds correct.

REALLY?! ...THAT SIMPLE ANSWER?!...

......??!

Anyway, so this gets the opposite if it were BNE, correct? or BNE is not compatible with CMP? What else is CMP not compatible or is compatible?

CMP compares two values, modifying the CPU flags accordingly, and you can use that information to make decisions in you program (branch or not branch based on the state of the different flags). I'm going to have to figure out ways to make drawings of it so it would be easier to understand.... So CM...

Expanding tepples' cmp explanation: Let's say you want to branch somewhere if Happy == 255. You might use: lda Happy cmp #255 beq somewhere ... somewhere: Though, for me, it's usually much better to change that branch to "bne +" and place the code you want run directly afterward. That way...

I don't know why no responses on other things that could help give insights; a lot of teachers in the past is willing to answer different questions that could help out students more. Being there for students even most ridiculous questions [at least in topic] raises confidences, curiosity, and trust....

No problem ;) If you want to use 6502 asm only it's fine too. What I just meant is C could have been easier if you just want to make a game. When you know enough 6502 you can try to use your 6502 with some C and that will be quite interesting to do! Knowing how 6502 and nes work is quite useful whe...

Help me help you. What specifically don't you understand about the concepts? Assume whenever I make a post, I feel I have already made it as simple and clear as I can. So telling me the explanation is complicated is not really feedback I can use beyond trying to explain some different way which may...

@DocWaluigean If your goal is to make a nes game only then you don't need to write code in asm: you can write it in C too. This is a lot easier to write actually. Even though I understand enough 6502 asm, I write my code in C and asm based on my need. For experimenting with the nes, you don't need ...

as you did say it's exactly as it's exampled, Except for the ldx #$1F above it. Like I said, you did not initialize X above the HATLOOP label. Compare: LDA #$04 LDX #$1F TOPHAT1: STA $0200, X DEX BNE TOPHAT1 to HATLOOP: STA $03A0, X DEX BNE HATLOOP At the TOPHAT1 label, X is #$1F, so it draws 31 pi...

Help me help you. What specifically don't you understand about the concepts? Assume whenever I make a post, I feel I have already made it as simple and clear as I can. So telling me the explanation is complicated is not really feedback I can use beyond trying to explain some different way which may...

I/easy6502/Nerdy Nights/whatever think way more about how to present information than I think you give us credit for. To be really frank, I do not think the simplest explanations are the ones that have had the most success here. "LDA will never change the value stored at an address." is a...

Whenever it seems complicated, take a step back. The mnemonic is separate from the addressing mode. LDA always copies a new number into A. It reads, rather than writes. It does nothing else. So LDA absolutely anything will never change a value stored at an address. (Well... in some specific hardwar...

Sorry for looong time. You pretty much know why. It's bad luck days for me earlier. Could you give me another examples or mnemonics about the ,x ,y stuff? I been reading it and I don't get it. --- -So the ,x ,y situations is that it allows you to copy from one Address Code into another Address Code ...

Let see if I got at least 99% right on it... ********************************************************************************************************* ********************************************************************************************************* *******************************************...

That's kind of true, I was going to say I was only speaking truth about my life but, now I realize that you ment, "That's kind of true about me," :) Also, thanks on never giving up! And praise God too. You're welcome. :) And :D P.S. I don't trust Lumosity who uses knowledges and brain tra...