Sinclair ZX80 / ZX81 / Z88 Forums

I think most programming started with a hex loader. A good place to start is Mastering Machine Code on Your ZX81 or ZX80, chapter 2. This chapter explains how to enter programs even on 1k. In this book, ZX80 is referred to as the "OLD ROM".

You need to use the Windows program to find which patterns are possible.

Two first words in my collection.

On the same home page, you can find the Celebration Demo. On this page your can download the Lightning Pseudo Hires Driver Source. With this source you can use many of the same tricks from the games. Try it out.

Andre wrote: ↑Mon Jun 07, 2021 4:17 am ANDRE***

Great to see you back at the forum. I personally love ZX91 magazines you’ve created.

Sorry I haven’t followed this thread. Big delivery at work. I haven’t made any special hardware to load files. I simply have a home made TZXduino, which standard firmware outputs 0V or 5V on a pin. This is fed directly into the EAR of ZX81. If you measure this on playback you’ll get the average 2.5V...

You don’t need GOTO 100, to restart, as the program will continue where it left off.

ZX81 does not support data files. But if you SAVE within a program, the state of the variables and program position is saved as well. When the program is loaded, the program continues, where it left off. Third party hardware might support saving any memory location to a file. Like ZXpand, ZXblast, ...

Maybe if it's always page $15, that is giving the error, you can post SCR15.F, and Alan can see what gets corrupted?

I’m glad you reread my question, because this was exactly an answer to my question. The “monitor” is a cheap B/W TV with no composite input, the signal is via the antenna socket. (Currently I’m working on building a ZX81 into a small French Minitel terminal. You can read a little about it on another...