Introducing FLEP adapters! These are intended to help you replace your broken or missing Bipolar PROM for arcade PCBs and other projects.

I had trouble finding a way to program old PROMs, often used on older boards for color information, so I decided to come up with a solution. FLEP stands for FLash/EProm, supporting 39SF010A (or equivalent) 1Mbit Flash or 27C010 (or equivalent) EPROM. The hard part is finding chips fast enough since the original PROMs were very fast. I have been using 55ns SST39SF010A so far with perfect results on older arcade game PCBs.

Available types:

FLEP-82S123-L and FLEP-82S123-R: 32 x 8 PROMs. Replaces 82S123, 82S123A, 63S081, 6331-1, 18S030, 7603-5, 27S19AC, 74S288, 5610, 7051. Also open collector variants 82S23, 6330-1, 18SA030, 7602-5, 27A18AC, 74S188, 82S23A. 

FLEP-82S129-L and FLEP-82S129-R: 256 x 4 and 512 x 4 PROMs. Replaces 82S126, 82S129, 82S130, 82S131 and their variants. 82S129, 6301-1, 24S10, 7611-5, 29661, 27S21, 74S287, 3621, 82S129A, 63S141, 7611A, 27S21A, 7052, 82S126, 6300-1, 24SA10, 7610-5, 29660, 27S20, 74S387, 3601, 82S126A, 63S140, 7610A, 27S20A, 82S131, 6306-1, 7621-5, 29611, 27S13, 74S571, 3622, 82S131A, 63S241, 7621A, 27S13A, 74S571A, 3622A, 82S130, 6305-1, 7620-5, 29610, 27S12, 74S570, 3602, 82S130A, 63S240, 7620A-5, 27S12A, 74S570A, 3602A.

FLEP-82S137-L and FLEP-82S137-R: 1024 x 4 PROMs. Replaces 82S137 and variants. 82S137, 6353-1, 24S41, 7643-5, 29641, 27S33, 74S573, 3625, 82S137A, 63S441, 7643A, 74S573A, 82S137B, 63S441A, 7643B, 27S33A, 74S573B, 7054.

All cross-reference data from Mike's Arcade.

A FLEP-82S123-L replacing an 82S123 at 6L on a Galaxian.

A FLEP-82S123-L and a FLEP-82S123-R replacing 63S081s at IC6 and IC7.


The page will be updated as I test more and more boards.

Game PROM 55ns? 70ns? Suggested Kits
Nibbler 2x 63S081 (82S123) Works Not Tested 1x FLEP-82S123-R
1x FLEP-82S123-L
Galaxian 1x 82S123 Works Not Tested 1x FLEP-82S123-L
Dig Dug 1x 82S123 (1R)
1x 82S129 (4G)
Works Not Tested 1x FLEP-82S123-R
1x FLEP-82S129-L

Price is $15 USD per unit, with a programmed chip, preassembled, plus shipping from Ontario, Canada. Contact me at This email address is being protected from spambots. You need JavaScript enabled to view it. for more information or to make an order.