OKay, I totally rushed it, but I've built a zikburner eeprom burner onto perfboard; this is a second one, a rush one -- the first attempt I started the other day was going great, but I was stupid and hooked up Vcc/GND swapped during late night test and made it unstable .. so I dismantled it all and rebuilt one nice and solid.
Its a poor arrangement (lesson: use a much larger perfboard than you need, so you have space to work in), which lead right to a poor solder job (so many wires in such a small area, that can't manueaver right and do a good solder job); they're solid, but it won't last forever.. I'm sure some wire will get loose eventually; I'll lay down some thick tape or epoxy on this sucker maybe, reduce the chance of that
Stick it into a project box maybe, so nothing touches the wire-side.
Something that keeps biting me when I make perfboards is ... order of operations; you need to plan where the components go (just like for a etched PCB), and its non-intuitive; you need to figure out how to place them to make wiring it up later easier; you need to wire in the right order, so as to not cover up parts of the board you need to work in later. For instance.. with RAM and EEPROMs and mcu's, youi've got a lot of wiring, all close together and often crossing over. Given 2 ICs that hook up like this on a board: A B B A, you should do B-to-B and then A-to-A, right? But its never that clear cut. As you can see, I ended up with abotu 3 layers of wiring, and it forced my hand for part placement. You'll notice that I used an 'ftdi basic' clone (as noted above why), and if you look at top side of board, you'll see I could have turned the hookup female eader for that 90deg, so it'd face out towards the LED and not stick out side of board; that was the plan .. but to do that, I should've put _that_ on first. Instead, I did all the work and obscured the perfboard region near there, so I had to turn it 90deg so I had somewhere to place it and reasonable access to solder it.
Also note .. the two headers on the side for cable hookups, are unused; this pcb was actually the start of a zikzak r3-r4 cpu or gpu board; the goal at _that_ time was to simplify the pcb wiring for the big zikzak r3 (the dual framebuffer crossing over schematic one); in this particular arrangement, you could have cpu boards, interconnect/crossover boards, gpu boards, and I/O boards; then you could hook up some combination with cables to make a computer, or reconfigure it in a few ways; a neat design, but in the end I moved to zikzak r4 'mini', which dropped a lot of features (no dual framebuffer or page flipping), but reduced the chipcount to something like 10 ICs, much more doable for us hobbyists hacking around
Annnyway, without further ado, here are 3 pics .. and I know, looks like shit.
But sort of awesome, no?
_and it works first time!_ --> jack in the FTDI; board takes all power from usb port, and talks usb/serial to PC; command line tool does dumps and burns, and you can use a terminal like minicom to use the command line interface in the firmware to do various functions.
Firmware and source, pics, schematics, etc are all up in the github:
https://github.com/skeezix/zikburner
Top-side photo, hooked up with usb:
Bottom (wire) side, the full mess; I have no shame
And a clearer top side shot, unhooked up:
What do you think?
jeff
