Sinclair ZX80 / ZX81 / Z88 Forums

Hello, does anybody knows how to access DS1302 RTC on zxmore from zx basic ( or C , or assembler)? I see on schematics that is conected to D0, but CE is also conected to RTC (IO1) of CPLD, so there is probably way how to get set time from it? If so, how?

And you could measure frequency at pin 12, IC9. Must be half of 6.410 MHz - so around 3.2 MHz. No, there is nothing there, then i figure out there is no connectivity IC12 pin11 and IC19 PIN11 so i bodged it with wire, after that i finally got stable grey screen 2016-01-18 20.20.34.jpg That should b...

Every now and then i got it to oscillate but it is not stable at all When i remove IC12 ( HCT125) i have firm 6.410 MHz and notice some activity on led when i connect freq meter across pin 12 and ground and got something on screen ( not a picture, some pattern - bars out of sync, but something is h...

Hi gemby, sorry to hear issues with your ZXmore. First: The latest schematic is available in this post: http://sinclairzxworld.com/viewtopic.php?f=6&t=1553&p=17474&hilit=ZXmore+schematic#p17474 Most known issues have been wrong or forgotten setting jumpers, be sure to use the BaseAddr set to A7 and...

Hello gemby, welcome to the forum :D Do ask for help here if you still have problems. If you don't get access to a 'scope, you may want to get a logic probe. A logic probe is much simpler (and so costs a lot less) but can tell you about static and slow speed digital signals, and can give you a "fee...

Hi gemby, sorry to hear issues with your ZXmore. First: The latest schematic is available in this post: http://sinclairzxworld.com/viewtopic.php?f=6&t=1553&p=17474&hilit=ZXmore+schematic#p17474 Most known issues have been wrong or forgotten setting jumpers, be sure to use the BaseAddr set to A7 and...

I have issue on first power up my zxmore :-/ Das not boot. No composite video signal. Nothing, checked with few monitors, and double-checked on original zx81 on them, they are all ok. Voltages are ok, i triple checked all components, i quadriplechecked all soldering points for bed joints and shorts....