Thanks for providing this pinout. I got my hands on a Ms Intellimouse trackball only to discover it won’t work on my 486 unless I have Microsoft 68666 adapter which sells for 5$ plus a thousand dollars shipping on eBay.

I was thinking of getting one of these ps2 bracket headers and modifying it instead for the correct pinout to my i/o cards com port. How cool would it be to be able to buy a bracket that had two 6pin din ps2 ports wired for Microsoft intellimouse and Logitech mouseman. I know there’s many adapters from each manufacturer but something like that would save a lot of headaches!

paradigital wrote on 2021-04-24, 14:03:

maxtherabbit wrote on 2021-04-24, 13:51:

I have several adapters, but none of them are marked. I also don't have a microsoft serial compatible mouse to test with. If you can identify a defining characteristic of the MS one I can see if I have it

From what I can find on the web, the MS adapter for this (and similar era) mouse will have 68666 stamped on it/moulded into the casing.

If you do have one that would be great, thanks.

I finally got my hands on a 68666, as well as what turned out to be an identical X03-55560 - a later version of the exact same adapter.

This pinout shown here is almost perfect but required two slight amendments:

TheMobRules wrote on 2021-04-24, 17:45:

[…]
Show full quote

Copy code to clipboard

1       PS2_1 <--> N/C
2[  RD] PS2_2 <--> DB9_2
3[ GND] PS2_3 <--> DB9_5
4[ RTS] PS2_4 <--> DB9_7
5[ DSR] PS2_5 <--> DB9_6
6       PS2_6 <--> N/C

This is the corrected version:

1       PS2_1 <--> N/C
2[  RD] PS2_2 <--> DB9_2
3[ GND] PS2_3 <--> DB9_5
4[ RTS] PS2_4 <--> DB9_7
5[ DSR] PS2_5 <--> DB9_6
6[ DTR] PS2_5 <--> DB9_4
7[  TD] PS2_6 <--> DB9_3

Thanks for that, so you are saying that pin 5 of the PS/2 connector is actually connected to both pins 6 and 4 of the DB9 serial port? Providing both Data Set Ready and Data Terminal Ready signals.

I'll have to dig out the machine and try again!

paradigital wrote on 2023-10-10, 09:37:

Thanks for that, so you are saying that pin 5 of the PS/2 connector is actually connected to both pins 6 and 4 of the DB9 serial port? Providing both Data Set Ready and Data Terminal Ready signals.

I'll have to dig out the machine and try again!

Yep

Huh, different again from the pinout I got working. Now I'm wondering if this was yet another design, or if I just got somehow lucky. I didn't use DB9 pin 6 at all, maybe it's used as some sort of loopback for the driver? Although Win98 auto-detected the mouse fine with how I wired it up. And I definitely needed RTS connected to both the PS/2 clock and data. I was using a model 45717 ps/2 with serial compatibility mouse, which might make a difference.

snufkin wrote on 2023-10-10, 15:33:

Huh, different again from the pinout I got working. Now I'm wondering if this was yet another design, or if I just got somehow lucky. I didn't use DB9 pin 6 at all, maybe it's used as some sort of loopback for the driver? Although Win98 auto-detected the mouse fine with how I wired it up. And I definitely needed RTS connected to both the PS/2 clock and data. I was using a model 45717 ps/2 with serial compatibility mouse, which might make a difference.

I would suggest you try wiring up that mouse this way and see if it works matching the original MS adapter pinout. I strongly doubt they changed the adapter pinout between generations.

maxtherabbit wrote on 2023-10-10, 18:18:

snufkin wrote on 2023-10-10, 15:33:

Huh, different again from the pinout I got working. Now I'm wondering if this was yet another design, or if I just got somehow lucky. I didn't use DB9 pin 6 at all, maybe it's used as some sort of loopback for the driver? Although Win98 auto-detected the mouse fine with how I wired it up. And I definitely needed RTS connected to both the PS/2 clock and data. I was using a model 45717 ps/2 with serial compatibility mouse, which might make a difference.

I would suggest you try wiring up that mouse this way and see if it works matching the original MS adapter pinout. I strongly doubt they changed the adapter pinout between generations.

Will do, need to get a few other things out of the way first. Agree that within one company I'd expect them to have picked one way and stuck with it.