EEPROM error on Dragon Blaze

[jessiewonka]

I have a Dragon Blaze PCB that's giving an EEPROM error on startup. It played fine for a while, but eventually freezes and restarts. Sometimes after turning on it just gives a bunch of frozen blue vertical lines and has to be turned off and on.

Someone with a Gunbird 2 PCB had the same error - http://shmups.system11.org/viewtopic.php?f=6&t=45866. The hardware is probably pretty similar, but I don't see the same EEPROM chip on the board that they suggested he buy, which did fix it for him.

http://jessiejohnson.net/arcade/2015-06-17-dragonblaze.jpg

[iankellogg]

U44 is the eeprom
its a 93C56 from microchip
You can buy that at just about any place since its still in production
http://www.mouser.com/ProductDetail/Microchip-Technology/93C56-E-P/?qs=cC9UkDmCsZvEW3U6q0LnNQ%3D%3D
for example.

[jessiewonka]

U44 is the eeprom
its a 93C56 from microchip
You can buy that at just about any place since its still in production
http://www.mouser.com/ProductDetail/Microchip-Technology/93C56-E-P/?qs=cC9UkDmCsZvEW3U6q0LnNQ%3D%3D
for example.

Hot damn. What about the one suggested in the other forum?

http://www.ebay.com/itm/251086240993

[iankellogg]

Yep the atmel one will work just fine. But that is coming from china so thats like 3 week delivery, mouser  is like 2 day delivery.

[jessiewonka]

Yep the atmel one will work just fine. But that is coming from china so thats like 3 week delivery, mouser  is like 2 day delivery.

I saw "factory lead time: 4 weeks" but they do seem in stock. Fingers crossed that a .75 cent part will be the fix! Thanks again Ian. 

Hope I don't botch such a tiny solder.

[iankellogg]

do you have solder wick and what soldering iron do you have? it isn't a dip chip and if you haven't done surface mount before you might want to slow down a bit and do some research.

[jessiewonka]

I have this Weller - http://www.amazon.com/gp/product/B00004W463

I do not have solder wick. I'll research while the chip ships.

[iankellogg]

You can buy solderwick from mouser. you will want noclean type and fairly thin. Do you have a thin chisel or thin conical tip? The iron should be okay.

[jessiewonka]

Yeah I may as well get solderwick there -- noclean, fairly thin. Mouser has 4 pages of solderwick!

I have the tip it came with and this one - http://www.amazon.com/gp/product/B00DK2D0MU

[iankellogg]

http://www.mouser.com/ProductDetail/Chemtronics/80-1-5/?qs=sGAEpiMZZMuzEnlwMwYUNp%2fXreKBr04MCjmpCIcPsIc%3d

That is very thin, which i prefer but you might want 80-2-5. I just like the thinner stuff since it seems easier to heat up.
Mouser doesn't seem to carry no-clean so this is rosin, which is way better than no-clean for actual work but it leaves behind a bit of a mess.

The tip will be fine. you might want to watch a bit on youtube to see how to do the work. if you need help though i am always available to help.

[jessiewonka]

I'll get this and get a no-clean elsewhere to try them both.

Already watching tutorials. And I'll practice on an old board first.

Thanks again Ian!

[iankellogg]

You'll only need one. The no-clean is nice because it won't leave behind a sticky mess but it doesn't work quite as well as rosin does. When you are done you will want to try to wash it off with alcohol or something.

[jessiewonka]

Noooo...



What I needed was 93LC56/SN.    Ordered.

[jessiewonka]

While waiting on the chips I pulled the existing eeprom. I took off as much solder as I could, but a little must have remained. When I got the chip to budge it pulled up two pads. Fortunately they just lifted, so it seems like they should solder back down ok. I hope.

[jessiewonka]

Replaced the eeprom, but now the board boots to a "security ng!" message...