Arcade board repairs, the odd console, vintage computer and general retro tinkering.
Friday, 12 March 2010
Converting Turbo Outrun to original Outrun
I made these pages for personal reference when I did the conversion but someone else may find them useful.
Outrun is a very flaky board due to it's age and being operated for decades. Working boards still fetch good money so some times it's cheaper to buy a turbo board and convert it.
From memory I halved the graphics roms and used 27512 eproms, and changed some 0 ohm resistor / jumper(s) to restrap the board. It was a long time ago, so cannot remember the details exactly.
I've got some Outrun boards to look at once I make a jamma adapter so will update with all the details when I have them.
After going through my faulty boards I've come to the conclusion that I used original maskroms from dead boards when doing turbo conversions.
That being said it is possible to use eproms either 32 27256s (ouch) or 16x 27512s with the data split and a PLD (PLS153) found on certain Turbo boards that allows eproms.
Mark @ retroclinic.com made a custom PLD that he sells which allows 27512s to be used and it doesn't require any jumper changes.
How did you manage to burn the Masked 1mb roms? As far as I know there is not 28 pin 1mb EPROM out there. (chips 1 - 8 on the video board).
ReplyDeleteFrom memory I halved the graphics roms and used 27512 eproms, and changed some 0 ohm resistor / jumper(s) to restrap the board. It was a long time ago, so cannot remember the details exactly.
ReplyDeleteI've got some Outrun boards to look at once I make a jamma adapter so will update with all the details when I have them.
After going through my faulty boards I've come to the conclusion that I used original maskroms from dead boards when doing turbo conversions.
ReplyDeleteThat being said it is possible to use eproms either 32 27256s (ouch) or 16x 27512s with the data split and a PLD (PLS153) found on certain Turbo boards that allows eproms.
Mark @ retroclinic.com made a custom PLD that he sells which allows 27512s to be used and it doesn't require any jumper changes.