Sinclair ZX80 / ZX81 / Z88 Forums

Yes, it works not perfectly, but good enough to autostart my web-server: it executes a LOAD "a" to load an autostart program to initialize the serial port of the server, load a filesystem into high ram and to start the server program. But my rom code does not initialize all BASIC system variables (n...

Hi Andy, the code of the NMI test is OUT ($FE),A ; start the NMI generator. ; Note that if this is a ZX81 then the NMI will increment AF'. ;; LOOP-11 L0216: DJNZ L0216 ; self loop to give the NMI a chance to kick in. ; = 16*13 clock cycles + 8 = 216 clock cycles. So if your ULA would immediately for...

I would second being able to autorun a program (unless a specific key was held down). If an autorun ("AUTOEXEC.P" ;-) ) program is started, it could also check itself some specific keys to STOP (so this keys need not to be checked in ROM). And if that specific key is "BREAK", no additional check wo...

see the thing with clock doubling is the short test in the rom to see if there is an NMI gen or not is too short when running clock doubled so 9 times out of 10 it thinks there is no NMI gen. Hi Andy, just a thought how to solve that problem: once Sinclair had a problem with an error in their ZX81 ...

Hi Zsolt I tested with the old SPONZY rom: What's happen if you (without tape recorder/cables) enter LOAD "" only? That gives also a completely white screen on my Zeddy (EO shows a black screen!). Loading with the Zeddy rom without any signal input gives a screen with a lot of white (broad) and blac...

Hi Zsolt, I did the same save/load test with a tape recorder and had the same behaviour (white screen during load). And I had some other problem, which I could reproduce with EO V0.52 (ZX81 with 48K ram and /M1-circuit enabled): when I enter the following program 10 for f=32 to 255 20 print chr$ f; ...

So... If anyone wants to lend a hand..I'm all ears. I just don't want to move too far away from the 'roots' if you will. That's why I haven't bumped the RAM to 64k. There is little software written for more than 16k so I haven't focused much on that area yet. Hi GTB welcome back ;-) Yes, there are ...

interestingly unmodified it does not work on eightyone if you have more than 16K ram installed, don't know why ? rgeards Andy "zxtricate" uses a complete different hires routine than other hires programs, which is NOT compatilbe with "standard 32K/48" Zeddie's hardware: the ram decoder remaps the 4...

Hi Zsolt I tried also SAVE and LOAD onto an MD-recorder instead of a cassette recorder. The MD-recorder works fine with my ZX81. I tried SAVE "test" and saw then black an white stripes on the screen. And something was written to the MD-recorder Then I did NEW LOAD "test" and tried to load the saved ...

Fred's programs present problems with real hardware. I've never been able to get them to run on anything other than an emulator. Perhaps someone here can shed some light on this? I would like to see them running as much as anyone. Hmm, I didn't have any problems to run a lot of Fred's programs (Bi-...