Sinclair ZX80 / ZX81 / Z88 Forums

Is it Wilf Rigter's hires demo? Wilf's "WRX" hires stores its hires image usually at address $2000 in ram (Wilf made and sold a static 8K ram card for that) . About /ROMCS-int (for the interal rom): never drive this line directly by an ic. You should only disable it (by using a diode to drive the li...

The ZX81 can only run software from 0 to 32768 (RT). So there is no possibility to merge the SD-card and sound part of PSG_E16M32 together with XPACK544. If you have an idea how to solve this, please let me know. The ZX81 can also execute code at addresses 32K to 48K, if a "M1NOT" modification is d...

You can make an empty screen with just 1 byte: #E9 = JP (HL) You can use the same byte also to shorten a screen. Display a few lines and then end the screen with JP (HL). Does that also mean, that the program is running faster (no more NOPs need to be executed, less time is "wasted" for display)?

There are some tests pending for an issue with HR graphics, which i hope to finish in the next few days. Hi Sascha what is the ussue with HR graphics? Are some pixels flickering? If yes, that is a timing problem Wilf Writer wrote about: the /MREQ-signal during refresh (while hrg pixels are read fro...

Hello community, Some time ago I've developed a tiny file system and a SD card adapter for the ZX81. The goal was to avoid a extra processor like ATTINY and only depend on hardware that was already available back in the 80's (apart from the SD card itself). The project comes back to my mind because...

I think, the first emu I have seen, is T0M's emu: https://forum.tlienhard.com/phpBB3/view ... p?p=13#p13

I copied my own rom into EO's rom folder and selected it as usual as the rom to be used by EO (instead of the ZX81x2 rom).
EO then behaves as usual as ZX81, but LOAD "" does not work (nothing happens).

No, because the program asked me, what my nationality is (I thought, the language used by the program would switch to German ).
So my first answer was wrong at the first program run ....

mrtinb wrote: ↑Mon Aug 05, 2024 1:57 pm EO containts both regular load and Flash load. Have you tried with both?

Yes, but no success ..

Now it works
My result: 46

Siggi