Sega FFB drive board compatibility

[chris2922]

Question about Sega force feedback drive boards - the notoriously prone to failure boards with the 7-SEG LED displays that show error codes.

According to this very interesting table (link below) the hardware that provides FFB control from Scud Race through to 18 Wheeler uses the same Drive Board just with different EPROMS and jumper settings.

On my F355 Twin for example one side uses the 838-13843 the table (and manual) says it should have. But the other side has a 838-13481 from a Daytona 2. The EPROM and jumpers have been changed to work with F355 and it’s fine.

So my question is are ALL of these hardware revisions interchangeable if the correct EPROM and jumper settings are used? Has anyone gone to the extreme of using the oldest revision in the newest game for example?

When searching for replacement parts is it ok to go for any of these ‘Type C’ drive boards?

Compatability_Tablechris29222021-12-14 21:50:31

 

[chris2922]

838-13366 also works with F355 despite being used in Sega Rally 2 and NASCAR.
So it looks like all are interchangeable regardless of game hardware.

 

[Anonymouse]

I have had a look into these board a little. These board use photocouplers as input relays which are prone to failure over the years. Maybe these are one of the weak links that are causing mass failure rates. I wont be home for a month and a half but I may consider replacing the photocouplers on one of my faulty boards.

 

[RenegadeR]

So did anyone find out what the issues are with these boards? I have a Scudrace Twin and both boards are bad!
The light comes on but 7SEG display shows nothing I took a board out of a spare Daytona 2 and replaced the roms, and now one side works fine but I rather have the boards repaired.

 

[Sbdesign]

So did anyone find out what the issues are with these boards? I have a Scudrace Twin and both boards are bad!
The light comes on but 7SEG display shows nothing I took a board out of a spare Daytona 2 and replaced the roms, and now one side works fine but I rather have the boards repaired.

welcome to the forum

 

[Retroman839]

As said above
The photo couplers relays look like a weak link,

Cn1. 10 pin header &. Cn3 13 pin header. Connect to

16 of em 16 smd resistors

Looks like 8 for player 1 8 for player 2

looks like the photocouplers convert the midi voltages into logic freindly
Output. driving the
Ic 17 -14 & 27 On the underside.

Could the 16 resistors be used to drive down the incoming voltage ?

and not be sufficient enough to protect the photcoupler from blowing?

Or is it just the photocoupler is a low grade quality. Simply not up to job over prolonged periods.( more likley)

Would be good if this board could be probed incuircuit and see if these parts have indeed failed ..

 

[RenegadeR]

welcome to the forum

Thanks! I'm happy to join this forum and meet you all. I can't wait to learn from your experiences and share mine. I'll post more about myself later today.

 

[RenegadeR]

As said above
The photo couplers relays look like a weak link,

Cn1. 10 pin header &. Cn3 13 pin header. Connect to

16 of em 16 smd resistors

Looks like 8 for player 1 8 for player 2

looks like the photocouplers convert the midi voltages into logic freindly
Output. driving the
Ic 17 -14 & 27 On the underside.

Could the 16 resistors be used to drive down the incoming voltage ?

and not be sufficient enough to protect the photcoupler from blowing?

Or is it just the photocoupler is a low grade quality. Simply not up to job over prolonged periods.( more likley)

Would be good if this board could be probed incuircuit and see if these parts have indeed failed ..

So i have at least 2 boards that failed and 1 that is working on which I can do some testing. What I noticed when connecting the bad ones to a power supply one of them there is the led quite bright and this one sometimes shows something on the display the other one is much dimmer so voltage drops down a lot more? And this one never shows anything on the display.

 

[Retroman839]

Prob showing er for error or an error code
Error codes are in the game manual

 

[Retroman839]

would be good to get voltage reading
From working and rest faulty one
And compare

 

[RenegadeR]

So what exactly you want me to measure? Should I attach the boards to scudrace or just power them with 5v?

 

[Retroman839]

Let’s find the schematics data sheet of the photo coupler
So we need the info of which photo coupler it is..
So yeh first ident the photocoupler
Then find data sheet
Then measure the output side of the photo couplers and compre good with
Known bad and see if we get differing results … if we do then we might
Be on to something.

Im not sure which leg is outputting
As I can’t tell which photocopler this is..
Looks ceramic ? Is it a Toshiba ?
It’s only a four leg so pretty basic
Assuming IC type photocopler

You could also take voltage readings
From the resisters and compare
From know good and known bad and compare..

I think ( Iv never done this ) Best to go into ffb test in game
Options..
So you can check ffb
And measure same signals each time
For consistency

Great info here

Force Feedback Translator - Sega MIDI, Sega RS422 and Namco RS232

I'm just kind of thinking out loud with this idea. I don't know when I'll take time to dig into it. I currently own an OutRun 2 Special Tours driving cabinet and have both the Chihiro and NAOMI 2 for loading up several different driving games. OutRun2 (Chihiro) and Initial D (NAOMI 2) utilize...

www.arcade-projects.com

 

[RenegadeR]

so both boards got different types one has 6G: P521 G making on it and other board has a single one that has 4 inside with marking 9706 TLP 512G-4 G2 tomorrow I will check on the machine.

 

[Retroman839]

The FFB has an opto isolator near its CN2 header where the wiring from the game motherboard connects. The opto isolator is a PC457L. Per the datasheet, here is a pinout:

Cathode is the signal output

 

[Retroman839]

Cathode is the output

The FFB has an opto isolator near its CN2 header where the wiring from the game motherboard connects. The opto isolator is a PC457L. Per the datasheet, here is a pinout:

Cathode is the signal output

So if you can identify the cathode leg
On the opto isolator I would say that’s where you want to take value readings from to compare

 

[Retroman839]

Cathode is the output

So if you can identify this leg
On the opto isolator I would say that’s where you want to read values