I've been having a lot of homework lately, and before that, it was mostly C/TI-BASIC, but I'm starting to get more into assembly again (and I'm a bit rusty, so I'm not completely sure of a few things). Anyway, I only have one question at the moment, but I'll probably have a few others soon. The question: if I do

ld hl,(label)

Then, does "h" contain (label) and "l" contain (label+1)? For example, if I had:

label:

.db 1,2

Would "h" be 1 and "l" be 2?

No, it would be the other way around (little-endian)

When do I need to reset the keyport when using direct port input for key testing? If I am testing for arrow keys and a few other keys, such as 2ND, could I just reset the keyport right before testing for the keys? Could I just do something like:


Code:



Also, does anybody know what registers _VPutS destroys? I've looked and looked and haven't found anything, even on WikiTI.

EDIT:

If I had strings set up like this:

strings:
.db "String1",0
.db "String2",0

And I did ld hl,strings \ bcall(_VPuts), then would hl point to the beginning of "String2"?

EDIT AGAIN:

It appears as if that is the case (that hl points to the beginning of the next string after calling _VPutS, which makes perfect sense)

Also, what should I do to flush out the key port so that if the user was already pressing 2ND, for example, he/she would have to press it again? The following doesn't seem to do the job:


Code:


Should I do some sort of dummy read with "in" instead?

Think about it this way: The key port keeps track of the keysets it's reading. When you output a value, it ands it with the current keyset value, thereby adding it to the list. When you output $ff to the keyport, it clear the list.

Incorrect. (hl) would contain a POINTER to 1,2. You'd have to bcall(_ldhlind) to get 2 in h and 1 in l.

Notice he wrote

ld hl,(label)

not

ld hl,label