Sinclair ZX80 / ZX81 / Z88 Forums

Ah yes thats it! Thanks!
I was feeding this with the address to the actual assembly code, but it needed to point to the basic command.
Good, this works! Thanks again!

Thanks so far for the information; Im getting the hang of it! I have another question; for my develop -> assemble -> run cycle time, Id like to make a .p file that automatically starts running after loading the program. (Now I have to type RUN and press enter). Is there a way to include this into th...

Ok, Ive spend a few evenings trying to digest whats being mentioned here. It seems to me that one of the tricks to gain more CPU for user program per frame is to display less `lines' of memory, e.g. have the CPU active less lines. I am still very much a Z80 noob, but from the code listings, I kind o...

Awesome, thanks, I will!

Thank you for the explanation. I knew the gist of it, but you uncovered a few very interesing points, like the custom display mode change the ratio of cpu spent on display mode. I was not aware this was possible.

Would you be able to point me to some more in depth resources regarding this?

I got this from the zx81Assembly.pdf; but it does not run correctly. Could it be that pushing and popping hl omitted and that PRINT taints it? It seems to run correctly when I wrap push/pop around the print. The other alternative is that I translated the PRINT call wrongly; I mapped it to BIOS (I gu...

Thanks!

Thanks! that is most definitely useful!

Ive started with ZX81Assembly.pdf by Timothy Swenson firstly, and Ill get through these as well!

Regarding CPU cycles (or are they called TStates here?); if the display is active, how many cycles does the ZX81 have for calculations each frame?

Regards,
Wietze

Ah right, I forgot that I had to push the play button on the tape manager to load the .p file.

It seems all is well. I can assemble the test program and run it!

Time to learn some z80!
Regards,
Wietze

Hi there guys, Ive been looking around on the forum for a bit, and decided to try my luck by just posting the questions ;). I am looking to code assembly for the ZX81. My computer is on 64bit OSX, and so far Ive installed EigthyOne using wine/emulation and Ive compile pasmo. I was wondering if anyon...