Help identifying PS/2 board

[tony359]

Hi all,

In my PS/2 model 30 8086 (ISA) I found this board. It's not serial or parallel - at least CheckIt doesn't see any additional serial or parallel ports - and there is nothing on it to say what it could be.

Any ideas?

Thanks!

 

[NeXT]

I was going to say it's an IBM 5250 or Enhanced 5250 emulation card but that has an extra metal cap on it.

Edit: "7373647 brings up a page of a guy decapping a similarly marked chip inside an IBM 5291 twinax terminal, so it might still likely be some form of a terminal emulation card if this was IBM sharing the chip between devices (and I'm reading the part number correctly)

 

[tony359]

Ah, I see thank you. So it'll just sit inside my PS/2 doing nothing! Too bad as it covers most of the motherboard!

Thanks for that!

 

[NeXT]

I'm not positive on that, FYI. IBM's chip markings were often inconsistent so I could still be wrong.

 

[tony359]

I shall take a look under the shield!

 

[NeXT]

Do not decap the chip.

 

[IBMMuseum]

Hi all,

In my PS/2 model 30 8086 (ISA) I found this board. It's not serial or parallel - at least CheckIt doesn't see any additional serial or parallel ports - and there is nothing on it to say what it could be.

Any ideas?

Thanks!

Sorry for the late reply - That is the initial 5250 emulation adapter, as reported. See the line at the bottom of the "silver-cap" ASIC starting '18440...'? As Ken Shirriff discovered, '1' is for the location of pin 1, then '84' is the year, '40' is the week (as is standard in the industry).

I think that is a single-session adapter (later IBM adapters were as much as four display/printer sessions) - but was unaware of the same ASIC being used in the 5291 terminal (since I am just having one sent to me).

 

[IBMMuseum]

Do not decap the chip.

Or send it to Ken Shirriff to do - thanks for the quicker reply than mine was. I have these 8-bit 5250 emulation adapters pictured at https://ibmmuseum.com/Adapters/5250/IBM/8-bit/

 

[tony359]

Thank you - and sorry for the delay! I haven't touched it, it lives inside the PS/2 (at least it doesn't take space). I guess I'll never know if it works! Thanks for the links @IBMMuseum !

 

[IBMMuseum]

Thank you - and sorry for the delay! I haven't touched it, it lives inside the PS/2 (at least it doesn't take space). I guess I'll never know if it works! Thanks for the links @IBMMuseum !

I have the diagnostic diskette for the later adapters at https://ibmmuseum.com/5250Emul/IBM/Diagnostic/ (the PNG image just shows what the diskette looks like; I should reduce it in size) - It should work for the earlier adapters since the I/O addresses are the same.