EL-wire triac switching

Well, after some experiments using a small coil of EL-wire and a 12v inverter, i have found that the MAC97A8 T0-92 TRIACs that i bought are just not fit for purpose... They run for about 30 switches on/off then the gate just dies. Looks like the SMT triacs on the el escudo are more than man enough for the task, but the MAC97's are somehow unsuitable, can't see why as the spec seems about right...

Arduino El Escudo

Well, i got two of these in the post today to help me with my EL-wire light driver project. They are available from Sparkfun here. I gave in and purchased these because my own triac-driving circuit was just not working, and after getting numerous shocks, destroying one strand of EL-wire and burning out 3 triacs I decided to see how others did it... I have yet to rebuild my own triac circuit and figure out just why it didn't work, but i think i might have been commoning grounds when i shouldn't have. Anyway, i made a video of the barbers pole in action!
The EL Escudo is aimed at the Arduino platform, but is essentialy an expensive bunch of triacs on a board, unfortunately the connectors are incompatible with any EL-wire or inverters that i have used so far, but there are pads next to each connector that you can connect up with your own fly leads as i have had to do. Annoyingly for external triggering, the board bereaks the triggers into 2x 10 pin header connectors, there are only 8 channels but they put the first 6 triggers on one connector and the last two on the other, and inexplicably they don't even match the spacing between these connectors so you can use one contigious connector. I had to use some spare proto holes andp ut in my own 8pin header and wire each trigger to each pin in turn. They could have done this a lot better.
Now alli need to do is to re-write the PICaxe 40x1 code to fit on a 28x1 and see if i can fit it onto the proto holes onthis escudo, i don't have the time at the moment to build my own circuit and get it fabbed, to get it to work i'll just have to improvise with these pcbs...
Checkout the youtube video!

Double Dragon finally!

I've been after a Double Dragon JAMMA PCB for ages, but I've not gone out of my way to find one, it has however taken along time for one to appear. Anyway, a recent batch of PCBs came in, and there was a sorry dusty looking PCB with missing legs and problems booting up. I saw that very briefly on booting up I saw a 'ROM 3 error', this turned out to be IC26.
The ROM was labelled differently to what is in Mame, but sadly it gave inconsistent reads, which caused the game to crash soon after reaching the title screen :| Its possible this is some sort of 'European' version, that's a total guess here because it has an 'E' on it... its labelled 21A-2 (with a '3' in biro on the label so '21a-2-3.25' for Mame) - interestingly, this actually romidents as 21j-2-3.25.
Anyhow, I finally found the 'world' revision ROM that corresponded to my set (21J-1-5.26), plugged it in and it fired up and it was fine, no errors! I haven't owned a proper Double Dragon PCB for at least 10 years so I'm keeping this one!

Konami Track n Field JAMMA Adapter

Well, I hate buidling JAMMA adapters, but i have come up with a method that makes it much more painless... I keep getting asked for them on my webstore so i decided to make a couple for stock. The key is to use the JB-3 fingerbaords available at jammaboards.com. The key is, always solder your smaller connector to the same position, and write up a wiring list for an adapter where you translate the JAMMA thru-hole designations to the 36-way connector designations. In this way you aren't constantly referring to several pinout sheets and flipping back and forth checking all the time, thats where most of the time goes! I can now make a plain Konami, or a track n field adapter in about half an hour now, much better!

Konami Hyper Olympic '84 Revision D found?

While working through my pile of Hyper Olympic '84 pcbs today i realised that the rom arrangement is different to Mame... whether the code is different or not i don't know, i'll leave that to the mame guys to figure out. All the roms are noted with a 'D' instead of mame which shows 'C'. Konami were fond of duplicating 99% of the roms across sets, but changing all of the naming. After tracking a bunch of tough problems and replacing way too many chips that didn't fix the fault, the pcb was 99% there... there were just a few bits of garbage left on the pummel horse round in the game character... turned out to be a bad rom at J19! all fixed.

Hyper Olympic '84 fixing

aka Hyper Sports, from Konami in 1984. Its a great game, but the pcbs are quite unreliable. I had one on the bench today that just looked so close to being working but its turned into a bit of a nightmare. Hyper Sports uses an alternating field setup, after spotting some manky looking signals at several custom pins i set about tracing them. I replaced several chips before i realised that Konami doesn't follow the regular rules of signal flow, ie, inputs at the left, outputs at the right, they often snake signals around to make the symbols fit on the schems. Unfortunately i didn't have my thinking head on, and was perplexed by the signals origin. Only once i was looking at the datasheet for a ttl chip did i realise the node in question was an output, hence the problem was in the opposite direction i was heading! It turned out to be no less than three bad 2114 rams (H8, J8, H9). The sprites were still wonky, 4bits bunched up at the left side of the screen but active, the other 4 bits spread all over the screen and static. A bad 74ls163 counter fixed the bunching at the side of the screen, but i can't track down the lack of proper movement on the other 4 bits. I can 'see' the CS of the SRAM isn't right, looks like a clock problem, but my head hurts and i need a rest before i tackle it further. I had sat down to do what i thought was a quick fix, nine chips later and its still not sorted :(

EL-Wire Barbers pole

I have a project on later in the year at a certain arts festival in Nevada that i need to develop some gizmos for. One of which is involving bicycles, and EL-wire... strange bedfellows maybe, but i need to develop a controller that can drive multiple strands of different coloured EL-wire. For development purposes i don't want lots of untidy wire hanging about, so i came up with a low-tech but effective solution, the EL-wire barbers pole!

The connectors for the 9 EL-wires are off to the base at bottom left, these will plug into my controller. The fixing is super low-tech Scotch tape (sellotape :) which is useless for anything long-term, but i don't want this permanently attached. The 'pole' is just a regular mailing tube, i happned to have white one kicking around, so it helps to brighten the el-wire even more!

Next stage, to build the controller, i'm thinking about re-using the code and technology from previous flourescent tube light drivers i built a couple of years ago, or designing from scratch again. I'll probably chicken out and go for a PIC Microcontroller technology i know and trust (and have loads of spares for already) PICAxe.

Blog opens!

> 10 print "hello world"
> RUN