VOGONS


First post, by mixedjames

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I'm currently assembling a retro PC system and, would you believe it, the mouse is causing me the most trouble. Not what I expected at all...

The Problem
The mouse does not move vertically. (Horizontal works fine, the buttons work fine)

My setup
Microsoft Intellimouse (the original shiny one with a wheel)
Dell PS/2 keyboard via AT adapter
Windows 95 OSR 2
Pentium 166MHz socket 7 in a Zida 5VDX motherboard with 8Mb of EDO SIMM
S3 Trio 64+ graphics

What I've tried so far
(1) Use the mouse in serial mode (the bottom suggests it is a dual protocol device) - doesn't work at all; searching here suggests that these old Intelli mice only worked with the MS 68666 adapter part. These seem to be hard to come by a no-one seems to publish the diagram.

(2) Taking the ball out and moving the rollers by hand - no change.

(3) Trying to use CTmouse - same problem.

(4) Taking the mouse apart and cleaning any adherent crap out. I've also had the pin-wheels (is that what they're called?) out and given the optical sensors a brief clean. I also can't see any obvious loose connectors - no change, and tbh not much crud to clean out anyway.

(5) Installing the Intellimouse drivers (though this seems mostly todo with the wheel) - no change

I had some trouble getting the PS/2 interface working - the 5DVX had a header but didn't come with a port so I had to get one. The pinouts are not standardised it seems so I got that wrong at first and it kept disabling the keyboard for some reason. Anyway, I think I had reversed the clock and data lines as switching these fixed the keyboard and Windows 95 suddenly detected a PS/2 mouse.

My current thoughts
To me this sounds like a problem with the mouse/sensor itself. I can't see why a problem with the port/header/mobo would specifically break vertical movement.

I guess I may just have to get a new PS/2 mouse. This seems like a shame since the Intellimouse was a lovely piece of kit and a lot of other dual mode mice seem to be much less high quality. Does anyone have any ideas of other things I could try before giving up?

Reply 1 of 6, by paradigital

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The pinout was confirmed by member “Snufkin” in my previous thread about the Microsoft 68666 adapter:

Re: Microsoft PS/2 to serial pinout?

Reply 2 of 6, by mixedjames

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Thanks paradigital.

I missed that. I guess I just need to find a full 6 pin adapter or try and cobble something together myself.

I'm not sure that's going to fix the issue though - has anyone else had this problem?

Reply 3 of 6, by chinny22

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You sure it's the mouse and not the PS2 port at fault?
I'd either try another PS2 mouse or test that mouse in a different computer just to be sure

Reply 4 of 6, by mixedjames

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Hi chinny22,

So I did some loft mining and found an old optical Intellimouse (circa 2000 I think) but which was dual protocol PS/2 & USB but missing the USB to PS/2 adapter. By shear good fortune my otherwise uninteresting local PC shop had an original Microsoft one knocking about.

This mouse works perfectly so the issue has to be the other mouse I think.

Anyway with the discovery of the "new" mouse my problem is largely solved. I'd still be interested if anyone's had any luck repairing an Intellimouse as I'd love to own a serial-capable mouse for the future. A new ps/2-serial adapter has arrived today so if it's a 7-wire one I'll see if I can try Snufkin's pinout for the 68666.

Reply 5 of 6, by weedeewee

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mixedjames wrote on 2021-07-15, 20:37:
The Problem The mouse does not move vertically. (Horizontal works fine, the buttons work fine) ... […]
Show full quote

The Problem
The mouse does not move vertically. (Horizontal works fine, the buttons work fine)
...

My current thoughts
To me this sounds like a problem with the mouse/sensor itself. I can't see why a problem with the port/header/mobo would specifically break vertical movement.

if possible, and you have a soldering iron, you could swap the sensor (led & photodiode) for the horizontal movement with the one for the vertical movement.
or just desolder'm and do some continuity test.
best case it's a faulty sensor, worst case it's the sensor input pin of the chip.

Right to repair is fundamental. You own it, you're allowed to fix it.
How To Ask Questions The Smart Way
Do not ask Why !
https://www.vogonswiki.com/index.php/Serial_port

Reply 6 of 6, by BitWrangler

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It's not unknown for the emitter or detector to go dead, but it's usually a rare occurrence.

Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.