Why mod.. when you can make?

User Tools

Site Tools


Table of Contents

Zik80 (and related) Revisions

This page is for actual pcbs that have been made (sent to boardhouse or home etched); for the 'mini prototyes' - the per component simple test rigging that are done on perfboard or breadboard, the only real documentation is in the code repo's comments ('wiring.txt' or 'hookup.txt' sort of notes, code) and photos. Naturally there have been dozens of the mini prototypes to try out the SRAM options, EEPROM options, keyboard, sound chip, each of the candidate mcu's, buffer switching etc and so on. But actual pcbs have been few, as the design gels.

And yes, its confusing, as over the years various phases of the project have been named Zikzak, or Zik80 (branched over to Z80 processor), to Zikzak SBC (single board computer variant) … and include side projects like Zikburner (for dedicated cart burner), Zikshield (add-on board for Zikzak SBC), Zok (atmega experiment board), Zikpower (power supply board), and others.

Component Revision and make Date Colour Notes
Zik cart rev1 at Elecrow Feb 2014 Green See blog posting - turned out quite well, with only minor things I'd correct for next time.
Zik power rev1 at Elecrow May 2014 Green Works well! Dual half-amp power outs for feeding into the other boards and keeping the upstream power supply from spiking and killing it all
Zik gpu rev1 at Elecrow May 2014 Green Works well but had 1 pin assignment error, easy worked around with a single jumper wire. Not fully tested, but basics work great.
Zik gpu rev2 at Elecrow June 2014 Blue tbd
Zik base rev1 at Elecrow June 2014 Red Works very well, but needs to have ps/2 keyb pullups added
Zik80 SBC rev1 at Elecrow August 2014 Red Works nearly perfectly but realized did not test sound + graphics before at same time; the AY-3-8912 fights with the bus and causes bad RAM reads; need another revision and probably change to AY-3-8913 with a proper /chipselect pin
Zik80 SBC rev2 at Elecrow Sept 2014 Red Process changes? font is differently rendered, board seems somehow different; seems the change to AY-3-8913 didn't take perfectly.. it is all wired up right, but things seem 'too fast' or otherwise noisy on the data bus, so the -8913 is not emitting sound. Moving the chip off to breadboard and jumping over from PCB socket to BB, and using GPIO-B for data bus to audio instead of the real data bus, and it works fine. (Argh!) .. I guess theres a rev3 in the future. Perhaps a RAM size upgrade as well, for lulz.
Zikzak SBC rev3 from Elecrow Nov 2014 Red Working perfectly .. audio is fixed; some other board revisions for convenience .. rotated the two ISP programming headers around, added some USB pads should they be desired in the future, and some other simple improvements. Quite pleased!
Zikshield rev1 from Elecro May 2016 Red Building tests now, working great so far; this add-on bord for zikza sbc rev3 will add actual jacks (such as vga jacks) to the system instead of relying on the ZZr3 base boards pinheaders; also adds audio amp, FTDI for usb↔serial without another board.
/home/skeezix/public_html/zikzak.ca/zikzak.ca/dokuwiki/__data/pages/zzrevs.txt · Last modified: 2017/11/11 02:58 (external edit)