@Ashbad, colons may not be necessary, but they increase the readability of your code and help when people are trying to help you with it. Not to mention, it is a nice style and makes your code prettier (which happens to be a big thing with me )

@David, I still don't really like the hEx thing, because it seems like you are doing so much more work than is necessary. But, to the xor a thing. xor REG8 takes an 8 bit register, and xors it with A. So when you do xor a, you are doing this: A = A xor A. If A is 10110010, then you are doing:
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Does that make sense?

Exclusive Or, yeah it xors a

Thanks a lot.

yeah, maybe I should add the colons when I post example code but I personally find the lack of them comforting much like how I adore uppercase.

Uppercase mnemonics make me sad :/ It is difficult to work on code when I keep thinking it is yelling at me.

To set where we place a string we can do:


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Can we directly do:


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It doesn't make you cool or manly to try to do things the hardest way possible. I feel like you really are making your life as hard as possible. What reason could you have for not wanting to use labels? @_player: I prefer uppercase mnemonics to no mnemonics.

no, we unfortunately cannot load constants directly into places in memory we have to settle for loading it in a supported 8 bit register first.

Not again.

Thanks Ashbad.

I have a new question!

ld (hl),l

This saves the address of hl in l right? Or does it save what's stored in hl?

I never really got the parentheses thing.

It loads L into the location pointed to by HL.

If the two byte memory addresses are next to eachother in memory you could perform a single 16-bit load to write to both at once. curRow appears before curCol, so you could do this:


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Remember that the Z80 is little-endian, i.e. the least-significant byte appears at the lower memory address.

it stored l into the address in memory pointed to by HL -- so if HL is equal to 50000, then it loads the value stored into L to the 50000th place in memory

I gave a bad example, I meant something like

ld l,(hl)

Does it store the address of hl in l?

Or for a more realistic example: if HL = $1245, ld (hl),l loads 45 into RAM at the location $1245.

Re: your earlier question. David, you have the storage order backwards. ld ($BBBB),a loads register a into memory address $BBBB, while ld a,($BBBB) loads the contents of memory at $BBBB into the accumulator.

Re: your new question: ld l,(hl) retrieves the contents of the memory named in hl, and stores that byte in l.

scout, yes, it stores the byte at the value pointed to by HL into L -- however, I don't know if L is a supported argument.

Yes, that is valid. For example, the four-byte way to do (infinitely faster) the three-byte opcode bcall(_ldhlind):


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Yes, L is a supported argument to ld reg8,(hl). I, too, would like to know why you dislike labels, btw.

Parentheses usually refer to indirection; rather than meaning "the value of X" they mean "the value stored in memory at address X".


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The one exception to this rule is jp (hl) which (confusingly) jumps to the value of hl; it's effectively ld pc,hl.

Thanks you all I got it. What if I did something like:


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Are the last two lines the same thing?

Actually, ld l,(a) doesn't exist But is there something like it?

ld l,(a) would be like:
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