Oct 252015
 

Another board from my friend ‘robotype’ and another quick fix.

I got from him  this Chelnov – Atomic Runner board :

Chelnov_PCB

It was stuck on this garbage screen:

boot_stuck

Main 68000 CPU busses were silent, no activity.Between 68000 and WORK RAMs (two 62256) there were some 74LS245 for communication between data buses.When I went to probe the one @F11, its pin 19 (output enable) was silent.I traced back this to another 74LS245 @E10 :

74LS245@E10

I piggybacked it and board booted fine :

successful_boot

I removed the IC and tested it out-of-circuit where il failed (it was from Fujitsu manufacturer):

74LS245@E10jpg

Board 100% fixed.

P.S.

For the uninitiated there is also an unreleased Sega Saturn port of this game (a copy has been afterwards located and disc image has been shared online).You can read more about here:

http://www.retrocollect.com/News/unreleased-sega-saturn-port-of-chelnov-atomic-runner-preserved-online.html

 Posted by at 9:11 am