Sinclair ZX80 / ZX81 / Z88 Forums

The Z80 CPU always runs at approx 3.25MHz. To keep costs low, Sinclair came up with a way to get the CPU to fetch screen data for display from memory. So there is no video processor in the ZX81. The CPU and ULA work together to do this task. So in the (normal) "SLOW" mode, the CPU has to produce th...

Ha, ha!

Yes I can see how a bit of "sliding" across the keyboard would be in order!


JR

Thank you!


JR

The "Why Wait" circuit will speed up SLOW mode by 10%. I have implemented this and sure enough it works. If I understand them correctly other hardware changes that have been implemented can improve the speed as well. 1. Clock doubler for use between screen refreshes 2. Switching to PAL 50 hz video ...

The 1000 hit the stores in mid 1982. Timex pulled out of the market in early 1984: https://books.google.com/books?id=kS4EAAAAMBAJ&pg=PA16&lpg=PA16&dq=timex+sinclair+1000+infoworld&source=bl&ots=mv50fveUwu&sig=FxobdjTBdQ38Pwy3l0xi-5fiMK4&hl=en&sa=X&ved=0ahUKEwiCx8qV2KPOAhWGFR4KHRDhAjsQ6AEIODAI#v=one...

You may want to look here, too: https://archive.org/details/@factus10 I remember when the VIC-20 and TS1000 shared space at Kmart... and at the local stereo shop. Fun times. Cool, you remember it too! What a great time that was! Computers were so new! I wonder was it 1981? 1982? 1983? Can't quite r...

Wow!

Getting used to typing on the TS1000 is quite a learning experience.

On one hand I love it and on the other I want to scream! Ha, ha!


I guess eventually it will become "second nature"...


Till then....


JR

mrtinb wrote:Great books:

• Sinclair ZX81 BASIC Programming
• The Ins and Outs of the Timex TS1000 & ZX81
• Hints and Tips for the ZX81
• The Complete Timex TS1000 / Sinclair ZX81 ROM Disassembly

Repositories:

• World of Spectrum Books
• wos.meulie.net

Thanks! SUPER helpful!

JR

Hi all, I tried searching on this topic in the forum and may have missed this answer (if it exists). A lot of retro computer's have a known website where many PDF books are stored that pertain to that machine. I have seem Commodore websites dedicated to PDF books to help with C64 learning. Is there ...

<Newbie Alert> I was reading in the original T/S 1000 manual last night about the slow/fast commands. I found this quite interesting and reminded me of my college days when the Pentium 386 was very popular. I remember some intel machines in that era had a "turbo" button. Slow/Fast, seems like a "tur...