Commando incorrect sprites

[stevebm1]

So the commando,I managed to bring back from the dead the other week has now developed a fault,where it is showing the incorrect sprites,the 2114 rams were all socketed,so I have already tried swapping them out,but still have the same issue,im guessing it’s something to do with sprite selection,any idea’s what chips to start probing?

 

[LHantz]

Schematics are included in the Manual, should shed some light...

http://pdf.textfiles.com/manuals/ARCADE/A-J/Commando%20[Instructions]%20[English].pdf

 

[stevebm1]

yes I already have the manual,I just need to know what chips are involved with sprite selection,other than the ram

 

[Ace`]

Commando PCB Repair

After replacing all the nasty sockets (single wipe rubbish) this Commando board worked but had vertical lines through the player and enemy s...

notinmame.blogspot.com

I fixed a sprite issue years ago which was down to a bad 74LS163, also suspect any fujitsu branded ttl in the same area (bottom board near the 2114 rams).

 

[stevebm1]

thanks mate,I will have a poke around with the probe,and see what I find

 

[stevebm1]

FIXED!,it was a bad 157 above the 4 ram chips in the middle of the bottom board,out of intrest does the bootleg not play the death sound when you shoot the soldiers?,all other sounds are present except that one?,I did notice the boot only uses one yamaha sound chip instead of 2 like the original board,despite having the space for it to be fitted

 

[sukhbir]

Well done! Those 157’s usually output the address bits to the rams so it seems there was an address issue.