ZXmore or the ZX80CORE follow-up

[PokeMon]

Well, it is possible to that some wire looses connection when soldering was not perfect and/or mechanical stress to the wires. And in fact it happened a few times during testing periods, resulting in a hang system which is hard to find with swearing like a trooper while trying to repair. This is not really fun.
But I got it after an hour or so as it sometimes looked like it would take several days to find.

[blittled]

Pokemon, I would be carted off by the men in white to a padded room if I had to wire that board Awesome job! If you make up a kit for the board count me in for one!

[fatbob_gb]

That looks absolutely mental, I would be a gibbering wreck attempting to debug that.

I too am looking forward to getting a finished board when ready.

[Andy Rea]

Good work as alwayd Karl, i love the rats-nest

i would be interested in a board / kit

Regards andy

[olofsen]

(ZX)More than fantastic, Pokemon! I would be interested in a kit as well!

[superfo]

i would be interested in a board / kit

[rune]

I'd be interested in one too.

[PokeMon]

Okay - here is a first bonus - a picture of the draft layout.
It's quite full even through use of a CPLD (see square PLCC socket) but I think it would be routable.
Keyboard maxtrix, edge connector and general size of board and mounting holes are unchanged, so it would fit into the provided acrylic case as well.

I changed something on the connectors, from left to right: Mic, Ear, Video, USB (2 ports/double stacked), power and a reset switch on board.
The reason for placing Mic and Ear left is to allow the easy use of ZXpand as well which normally collides with the video chinch socket - so the chinch socket moved. It is possible to power the board via external power supply or alternatively via USB. I am not 100% sure if USB power supplies are good due to many switched mode power supplys and some terrible noise on 5V which could affect picture quality more than a line regulator but placed an inductor as well on the board. We will see - my home plasma TV with 42 inch shows some nervouse edges on the letters on screen but this may depend on monitor, size and power supply. The power consumption is not hard, would be approx. 110-120 mA.

Finally I added now a RTC device as well (DS1302) for having an accurate date and time in the systems. This is not supported by ZX80, ZX81 and even ZX Spectrum but would be available when using CP/M as well as having accurate time stamps on files created on the USB stick when storing data or programs there. The USB device is placed at the bottom as the one and only SMD component which is premounted/soldered with the board itself when delivered.

The placement of the chips is not final - I have to check and maybe improve when routing the board. We will see soon.

[Andy Rea]

wow thats pretty packed, is it not possible to combine more of the logic into another cpld ?

Regards Andy

[sirmorris]

^ I was wondering that too.

There is no shame in VHDL