82s126 82s129 82s131 adapter board and 82s123

[patzik]

I read in another post that someone needed replacement proms and so I decided to share the gerbers for an adapter board I designed a while ago.
The adapter board takes a winbond 27c512 eeprom, that can be burned with the prom file, no need to adjust the size of the file. On the back of the board are instruction on how to set the solder jumpers.

patzik2021-06-29 23:23:55

 

[patzik]

While I am at it, here's another one for the 82s123

 

[TheDaddy]

Looks good , have you had these printed ?

Dave

 

[MarcoZ]

nice cad. btw. did you know that a 27512 is not as fast engough as a 10ns bipolar PROM ?

 

[sukhbir]

Yeah I agree,most 27512 are nowhere near 10ns and even the winbond type access time is 45ns.best to use the correct proms.buying adapters and eproms the cost will climb.

 

[MarcoZ]

ok I looked up the datasheets:

TS

82S129 (50ns) 6301-1 TBP24S10 HM7611-5 29661 27S21 74S287 3621 MBL8521A

82S129A(27ns) 63S141 TBP34S10 HM7611A - 27S21A - 82S27 27S11

TS 82S123 (50ns) 6331-1 TBP18S030 HM7603-5 - AM27S19 - - 82S123A(25ns) 63S081 - - - AM27S19AC 74S288 - 63LS081 AM27S09 AM27LS09 DM8577

OC Yes if you need opencollector - you can´t use the eprom by far...

82S126 (50ns) 6300-1 24SA10 HM7610-5 29660 27S20 74S387 3601 MBL8520A

82S126A(30ns) 63S140 - HM7610A - 27S20A - - 27S10

OC

82S23 (50ns) 6330-1 TBP18SA030 HM7602-5 - AM27S18 - - 82S23A(25ns) 63S080 - - - AM27A18AC 74S188 - 63LS080 AM27S08 AM27LS08 DM8578

Ref: https://people.zeelandnet.nl/wgeeraert/pdf/TTL-BIPOLAR_PROM-RAM_REFERENCE_GUIDE_V5.pdf

 

[MarcoZ]

the next problem I ran into was the fact that on some pcbs

the proms are so near togheter that you cannot put 2 of the adapter side by side.

And in one case I can´t plug the eprom adapter on top of pcb - because another pcb was stacked on top of mainboard. Not enough space between. I think it was taito ....

Really like your CAD Skillz !! And thank you for gerbers.

Did you try the pcb in a real pcb ?

 

[John Bennett]

Wow, was there really 10 nanosecond PROMs out there in the 80's?! (I know very little about them other than translating one into a GAL for Outrun DLX).
Lovely PCBs

 

[patzik]

Of course if you have the ability to burn the original proms, that would be a better option. But let's face it, most of us don't and in that case this can be a saviour. I have had both boards made and have tested the 26 39 31 adapter in a few boards that I repaired and so far it worked every time. Last board I remember using it for was a crazy kong. Even if a prom is 10ns it doesn't always mean the board really needs this speed. The 123 board I think I haven't used yet, but it should be fine.

 

[MarcoZ]

yes its all about try and error with arcadehobby I know - btw I use my DataIO 29B for this kind of burnjob.

 

[philmurr]

You're very unlikely to need anywhere near 10ns access time in a game of the era that uses such chips

In excess of 100ns is usually fine, and I've never seen an issue when I've used Winbond 45ns EEPROM or Atmel 45ns / 70ns OTP PROMs

 

[GadgetFreak]

Yeah I agree,most 27512 are nowhere near 10ns and even the winbond type access time is 45ns.best to use the correct proms.buying adapters and eproms the cost will climb.

Really! Have you seen the cost of NOS Proms? Most types are in the £5 region. A pcb, header pins and winbond eproms cost much less.

 

[MarcoZ]

yes sure. I buyed my proms in the late 90ties in my electronic store next my apartment. packaged in little sticks a 25pcs as I remember...

at the moment I´m shocked how expensive this little buggers are - c r a z y

btw. I buyed last year some adapter pcbs from a nice member here for

conversion hacking - as I experiment with different Color Lookuptables / Palette datas - for my multigame pcb experiments - and yes for that is the adapter very helpful as I often reprogramm them to test things...

Cheers

MarcoZ2021-07-09 20:21:09

 

[Cbadger]

While I am at it, here's another one for the 82s123

https://www.ukvac.com/forum/data/uploads/6230/82s123_2020-09-29.zip

Hello, Just checking the size...
Uploaded at jlcpcb and the size is 160 mm* 100 mm. Is this correct ?

 

[patzik]

Hello, Just checking the size...
Uploaded at jlcpcb and the size is 160 mm* 100 mm. Is this correct ?

No that's not correct, it doesn't seem to find the outlines correctly. I will look into this and post new berbers when I have time,

 

[Cbadger]

No that's not correct, it doesn't seem to find the outlines correctly. I will look into this and post new berbers when I have time,

Thank you.

 

[qjuk]

I’ve done my own gerbers for a 82s126/9 adapter which I’m happy to pass on the file if you need it.

I’ve also done an adapter for the 82S123, however it’s integrated in a PacMan SBC pcb, so it might not be what you are looking for.

 

[patzik]

Uploaded new gerbers for both boards, these should work now.

 

[fiodena74]

Sorry, to use this adapter with the 82s131 how should the jumpers be set on the back of the PCB? Thank you

 

[qjuk]

Sorry, to use this adapter with the 82s131 how should the jumpers be set on the back of the PCB? Thank you

According to the silkscreen on Patzik’s adapter; pins 2+3 on the top pad are soldered together and pins 1+2 soldered together on the bottom pad.