Sinclair ZX80 / ZX81 / Z88 Forums

Here's a head-to-head comparison between the ZXSimulator and the Spectrum ZX81-Emulator running the BANNER.BAS program (square pattern through normal and inverted for a full loop) with EightyOne running in 50Hz PAL mode. ZXSimulator on unexpanded QL: 100 seconds 97 seconds (fixed a small bug that sl...

Also the PLOT coordinates are different. BTW, I figured out how the ZX81 handles the PLOT coordinates. It does not use the character map for it but does try to work with the existing character map. When it is about to plot its 4x4 "pixel" into an 8x8 square it first checks each 4x4 quadrants to see...

The file starts with a convertor to alter .P into TAP. Second program is the emulator, so just BREAK and load again. Hi, So I got it loaded and running in the EightyOne emulator under Spectrum 48K modem. EightyOne does have some weird behaviors that I'm hoping you can help me with: It loads the ZX8...

This one.. https://www.worldofspectrum.org/infoseek.cgi?regexp=^ZX81%2dEmulator$&pub=^YRS$ So a few questions. When I go to the page there is a ZX81Emul.tap file and when I put EightyOne into ZX Specturm 48K mode I can load that in and it seems to be a tape loader program. Where is the ZX81 Emulato...

My ZX81 emulator uses another way since I didn’t have so much memory on a ZX Spectrum. This is slower but still is the quickest way on a ZX Spectrum. Same routine is used on Galaksija-emulator for the SAM Coupe. Which one is your ZX81 emulator? Sorry if that's a dumb question. I'm newer to the ZX81...

So Z80 has 252 instructions and you are saying that using 2 bytes per for 252x256 which equals 64512 (or the full 256x256 for efficiency at a full 64K) so that each instruction is a memory address of the high byte (which means some memory is completely unused assuming not all opcodes need 256 bytes ...

Oh that's very sad to hear. I've seen the Xtricator running and it looks like a very sophisticated and a polished piece of software. I was trying to run it on the Q68 but hadn't set up my directory environment properly. My ZXSimulator won't be as compatible as that since it won't emulate the Z80 and...

Yes, I've seen them all on the QL. I may upgrade the ZXSimulator to a full blown Speccy once I get it up and running and working for this first phase. I'll have to learn Speccy BASIC to see how many new things it adds. The Commodore 64 has one so I figure the QL ought to be able to support most of w...

Thank you. Yes, I should head there. I need to dig out my ZX81 from my closet. I do have a TS1000 handy but I have an old mod'ed ZX81 (in a homemade case an all with real keyboard) that I should resurrect. With the current version of ZXSimulator I wrote some simple BASIC programs: ball_bas which is ...

Hi folks, My first post on this board. The ZX81 was my first ever computer when I got it in 1982 back in the US and is the computer that introduced me to coding both BASIC and machine code. I have very fond memories of it. At the end of the 80's I upgraded to a Sinclair QL and then in the mid 90's l...