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GoodToGo!
29th October 2008, 07:46 PM
Howdy all!
Long time lurker, first time poster!

Anyways, some repair log stuff.

Commando Bootleg.
Purchased amongst a batch of boards. It’s a 3 board stack basically identical to the original Capcom boardset, except a lot of jumper wires for where the manufacturer’s stuffed up the copper traces. (Wrong connections, missing connections etc.)The Custom chip is replaced with a plug in PCB populated with other chips.
Id’ed the EPROMS, found position 9M on middle board no good. New one burnt.

Adaptor made and board powered up with the following graphic faults.
The background graphics were all corrupt, The whole lot being exactly the same. Game play ok. Fault traced to dead 2016 RAM at position 2B on top board. (Was getting very hot!)
Next fault to rear its head, there were yellow dots appearing in every other line in the helicopter at the start. This was traced to a broken jumper wire at pin 6 of the 6148 RAM at position 9M on the lower board. Wire re-soldered and dots now have gone….. only to be replaced with…….
Every 2nd line in the characters were now missing! (Trees, helicopter, etc.) Well, the RAM at 9L (again a 6148) had gone the way of the dodo. RAM replaced and now THAT fault was fixed.
After a bit of game play, I noticed the graphics were freezing up, but the gameplay continued in the background. After a heap of troubleshooting, I found the fault could be reproduced by flexing the lower board. Unfortunately this is where most of the jumper wires are soldered in. After careful examination of the board and all connections, and re-soldering many suspect dry joints, the fault was eventually traced to pin 20 of LS245 at 1E being actually bent under the chip and not through the solder pad on the board! Therefore it was only making intermittent contact. I de-soldered the IC, straightened the offending pin and re-soldered it back into the board.

Game she all work good now!

(Edited due to friggin' IE 8 has trouble with the 'enter' key!)

Cheers!

GoodToGo!

Womble
29th October 2008, 08:54 PM
Nice work, its a great feeling to bring a board back from the dead, dangerously addictive I find.

Davefjedi
30th October 2008, 07:27 AM
Yeah good work I used to love Commando so bad even on the C64 it rocked