Pac90 (silly noob question).

[sebastian17]

I have an old World Cup 90 (original Tecmo board) which I wish to change into a Pac90. While I have noted the roms/eproms that need replacing on the board could someone tell me if this is correct (as below)? Moreover, now the really dumb question, I have noticed that the ic85, 1c50 and ic60 chips are soldered onto the board - do I need to completely replace these chips?? i.e. resolder them whenever I want to 'switch' between games?

ic87
ic67
ic54
ic85
ic50
ic60
ic82

[mikejmoffitt]

You'd want to socket those chips if they aren't already.

Pac90 is interesting, but it has a few bugs in the ghost AI that the original does not have. Just keep that in mind.

[mastercello]

You can save your work and just buy mine here: http://shmups.system11.org/viewtopic.php?f=4&t=54697

[sebastian17]

In regards to the socket chips - I'm guessing I am going to have to resolder some of the chips on my board? Did you [mastercello] have to resolder chips on your PAC90 board?

[mastercello]

Here is a picture of mine (one side) - all the stuff is on sockets now, so you need to solder in sockets or solder in the new EPROMs.
https://wshdyw-db3pap001.files.1drv.com ... jpg?psid=1

[sebastian17]

Thank-you, I was worried about the soldering - I'm actually really bad at it!!! Moreover, I needed to practice my eprom programming, so I thought I'll reprogramme the board (I think I will get a friend to resolder!!). I have uploaded images of the 'soldered' chips, these seem to be the 'only' chips that I need to change which are soldered to the board.

[mastercello]

Why would you change them?
This are TTL logic IC's - you only need to change the program code which is on the ROMs, EPROMs!
The ones with the white label in my picture.

[sebastian17]

oh, ok - I get it now, so the 'only' eproms that need changing on the board are ic82, ic54, ic67, ic87. I got muddled up when I downloaded the pac90 MAME rom and saw the 'other' chips: ic85, ic50, ic60!

A really big thank-you!!!

[mastercello]

You have to change them too, IC85, IC50, IC60 are on the other pcb....they are also ROM's or EPROM's

[sebastian17]

Got it... was looking on the wrong side...

I have uploaded two images 'top' side and 'bottom' side, of the eproms numbered (that I need to change) I have coloured these in red.


Top Side:


Bottom Side:

[mastercello]

Exactly....i guess they are all in sockets...so no Need to desoler/solder something

[sebastian17]

Thank-you, I got there in the end... and no soldering either

Do any of the eproms need taken from the board? I only ask because I have seen two images and both have eproms missing (compared to a standard World Cup 90 board)?

I have highlighted the 'missing roms' in blue.

Top Side:


Bottom Side:

[mastercello]

I guess so yes....mine on the top board has them neither...

[sebastian17]

ok thanks... that's it - all sorted

Thank-you!!