Sinclair ZX80 / ZX81 / Z88 Forums

Thanks for the heads up - I have amended the web page accordingly - Bruno - can you please clarify about the TS2048?

Well, I sell Zaxon's AY interfaces for the ZX Spectrum - see http://www.rwapsoftware.co.uk/spectrum/ ... ounds.html

I also would like to see a version for the ZX81 and have emailed him accordingly

Now if the TS1510 can be used with a ZX81, then there should be a market out there for it - all we need is an easy means of having a cartridge with Flash EPROM, so that it can be used for saving and loading!!

Thanks for the information - very useful - now can someone remind me, what the TS1500 is and how it compares with the ZX81 / Spectrum?

I presume you mean the changes which I have uploaded, which were suggested by Thomas Bent or do you mean all of the changes suggested by the disassembly on Geoff Wearmouth's pages? If you have compiled the amended code, can you please confirm what the corrections are to the highlighted lines please ...

I have now uploaded an article by John Oliger (originally published in the Syntax magazine - Summer 1983) which describes the modifications to enable you to use the 32K-48K RAM area for machine code. This is known as the NOT M1 decoding circuit. This also includes further articles by Jeffrey D. Moor...

Alas there are no binary files as yet - I am not certain about some of the codes!!

I have finished uploading a file based on the suggested improvements to the ZX81 ROM made by Thomas Bent. I have updated the listing changes so that they are based on Geoff Wearmouth’s incomplete disassembly of the ZX81 ROM – see http://www.wearmouth.demon.co.uk/zx81.htm, which itself takes account ...

I have entered the instructions on how to convert a ZX81 ROM Socket to support a 2764 EPROM - this is essential if you want to upgrade the ROM.

Please let me know if any changes are required to the instructions document.

They actually sell well on ebay dependent on a few factors: a) What your ebay reputation is like b) Whether the plastic is still white and intact (some ZX80s suffer with the plastic going brittle) c) Whether it is tested and working. If you like, I can sell it on your behalf for 25% commission as I ...