SP

[darkstone knight]

is there anny way to save SP in a register? LD HL,SP doesnt work

[Ed H]

Maybe if you split that into two load instructions?

[darkstone knight]

nope -.-

i want to save sp so you dont have to clean the stack at the end of the program (saves space...and time, my programs stack usage is a mess)

[calc84maniac]

Just do something like:

[darkstone knight]

it does work

but wabbitemu still crashes when i exit my prog

[Spencer]

In the long run you'll be much better off making sure your stack usage is correct. As for the way you're currently doing it, make sure you didn't change the value of IY. If you did, make sure to save and restore it like you did SP.

[darkstone knight]

i probaly did someting wrong in storing data...

thanks annyway

btw, my stack usage is probaly correct, just to be sure the mistake isnt in my stack

[tr1p1ea]

You arent using interrupts at all?

[darkstone knight]

no... its my first asm prog ever (check sig)

[magicdanw]

I don't really see how this can/should work. If you push data onto the stack, you must always pop it off. If you just reset the stack pointer without popping stuff off the stack, at the very least it'll cause a memory leak, and at most it'll crash the calculator.


You should never be messy about stack usage, especially the SYSTEM stack! If you're just storing data you want to get back later, use a safe area of ram, not the stack. It'll be much easier, trust me.

[brandonw]

[darkstone knight]

it works now, turns out i POP'ed whoutout a PUSH first, eh....

edit: when the program exits, it stays at the graph screen... i want i to return to the home screen, how?

[DarkerLine]

Use bcall(_Disp) to display the home screen (i.e. the ASCII characters stored at (textShadow)). This will not clear the graph buffer, though, you'll have to do that yourself.

[darkstone knight]

thanks :)

program is nearly done, but for some reason, it has memory leaks -.-

[magicdanw]

If you need help figuring out what's wrong, you can post code here, and we'll take a look at it.

[darkstone knight]

the code (first prog, again) kinda sucks

i promise i will make my next program better

comments are dutch btw... most of em

to draw a "box" the box is simpely inverted

[magicdanw]

Hmm. I don't see anything that would obviously cause a memory leak, but one thing I notice is that you don't have very good structure of routines. I'd like to suggest structuring the code that it is obvious what sections are part of specific routines, and use routines that can be called and return, rather than specific ones that you jump to and then proceed to jump somewhere else. This makes it rather hard to follow program flow and to debug the problem.

[DarkerLine]

Some additional tips on routines: I'm going to talk about "wincheck", but what I'm saying may apply to other places in your code too.

First of all, it's good practice to use the "call" instruction when you're calling a routine. Yes, you can sometimes do it with jumps the way you do (although in that case, it's also unclear why make it a routine in the first place, it might as well have been inserted inline). But supposing you want it to be a routine for clarity, it's best to call it using "call", and exit using "ret".

With that in mind, it's often not a good idea for the routine itself to handle things like "exit if there is a win". A better way to approach the problem is to return "did the player win?" in a flag such as Z/NZ, and handle that when the routine exits. For example:

[darkstone knight]

mhh... thanks

the next time i try to make a game, i organize all small routines BEFORE i start programing

[asdf]

@DarkerLine: Btw, "cp 0" and "ld a,b" are unnecessary because "dec b" will set the Z flag if b=0 after decrementing. Also, "ld a,hl" isn't a valid instruction, i think you mean "ld a,(hl)"? And in your mainloop label, be careful with the stack. That code is fine, but take notice that you push hl then jump somewhere else before popping the value back off the stack. The exit label will need to adjust the stack to make sure the program doesn't have stack trouble.