Why do you need to use a USB mouse?

Does your 486 happen to have PCI?

smeezekitty wrote:

Why do you need to use a USB mouse?

Does your 486 happen to have PCI?

Because I'm using my 486 on a KVM switch, which is shared with a modern computer. I don't have the room to have a separate desk for my old retro computer, and I really don't want to use two physical mice on the same desk.

It does not have PCI.

This is a common problem. Lots of threads here on Vogons. No one has been able to come up with a cheap and good solution.

I've seen this device suggested here in the forums before. Not cheap, and someone suggested it doesn't have the best tracking in the world, but it is the only thing I can think of.
Alas if you are really desperate and good at programming you could get something like a PIC24 and make an active adapter yourself... but this isn't exactly trivial

How about simply obtaining a mouse that is a real (and modern) PS/2 combo mouse? The mouse could be used with an active PS/2 to USB adapter on a modern computer, and normal (dumb) PS/2 to serial converter on the old computer.

PS/2 to USB adapters are highly unreliable from my experience. 😉

I wonder if you could do something with a microcontroller like an Arduino or a Raspberry Pi that accepts a USB mouse and spits out a serial connection through the GPIO pins.

There is also this (Raritan Computer APSSM):

I bought it about 2 years ago from Amazon as used. I certainly works, but the cursor speed is sickeningly slow, so it practically useless when it comes to games and such. My active retro rigs which are connected to the KVM setup has all PS/2 mouse capability, but I still use an additional serial mouse whenever I want to play with my 386s, instead of this gadget (my 486 was also PS/2 capable before its death a year ago).

Thanks for the suggestions. Slow latency or other issues that affect gaming are simply not acceptable.

How about a PS/2 interface ISA expansion card? Does that exist? What are they called?

If it does exist, I could just use that to add PS/2 ports to my 486 and the problem would be solved.

How about a PS/2 interface ISA expansion card?

Lots of people have looked but it appears not to exist.

I have heard of a mod that lets you connect a PS/2 mouse through the keyboard controller but I don't know anything about it.

Here is an ISA USB card: http://www.simtec.co.uk/products/EB1161ISA/gallery.html

But it appears to be unobtainium

An ISA usb card would also need a usb stack/driver that would suck both memory and cpu time. Not a good solution.
I also have the Raritan , it seems OK in low resolutions like 320x200 games , the lag becomes more apparent in higher windows resolutions.

Let's not forget that sklawz created a serial->ps2 mouse adapter as well: PS/2 to Serial Mouse protocol converter
I never came to build it though, so I can't personally comment on it's efficiency. I don't see it having problems though, especially in DOS.

We have a cheap solution for boards based on Award BIOS, but at present it requires quite a bit of skill to get it working. User "feipoa" figured out a way to hack the keyboard controller and BIOS, but his solution requires modification to the motherboard. I adapted this to an adapter that fits under the keyboard controller, but it's still a little rough around the edges. I am planning to build a second prototype in the near future. We know for sure it works with a modded AWARD BIOS, and it may also work with MR-BIOS.

Unfortunately AMI BIOS is still a major issue. The mouse support in the BIOS needs to be enabled, but we don't yet know how to defeat or recalculate the checksum. However, on the internets there is source code floating around for an AMI BIOS, and for someone with software skills it might be pretty easy to writea program like modbin for AMI BIOS. Or if somebody has old copies of AMIBCP we could use that as well, but my searches have been fruitless. I think we need V2.1P and earlier (for hi flex bios)

There is this: PS/2 to Serial Mouse protocol converter

I bet the design could be adapted to work with a USB mouse.

As AC pointed out, the best approach thus far is with modifying the KBC, as shown in this thread, Native PS/2 mouse implementation for 386/486 boards using the keyboard controller
I finally renamed the thread to something more fitting, "Native PS/2 mouse implementation for 386/486 boards using the keyboard controller"

I have been waiting for someone else to attempt sklawz's PS/2-to-serial protocal converter. I spent A LOT of time trying to replicate his efforts, but to no avail. This adapter has promise to be faster than those commercial units with poor tracking quality (Raritan, Vetra, various KVM's), but there will always be some loss of tracking fluidity.

From what I understand, that ISA USB card is without Windows/DOS drivers. I had the opportunity to get some at one point, but decided it wasn't worth the risk.

I beleive the best approach for now is for native PS/2 mouse implementation via the keyboard controller. While AC has an alpha prototype of a plug-in module for this design, I beleive it may be too tall if your KBC socket is in front of a needed ISA slot. Ideally, it would be desirable to relocate the PS/2 module to an ISA card, making such a design platform independent.

I had the opportunity to get some at one point, but decided it wasn't worth the risk.

At what price?

Based on that reaction I would guess rather $$$

Do optical/laser mice of today actually support serial mode function?
I thought only old ball PS/2 supported it...

tayyare wrote:

There is also this (Raritan Computer APSSM): […]
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There is also this (Raritan Computer APSSM):

Anonymous Coward, is this the device you use on your ultimate 8088 (er, V30) system? I've been meaning to ask after reading about it.

Yes. that's the same adapter I have. Since games on these old machines run slow and I don't normally use graphics resolution higher than 320x200 (in the rare case 640x480) I find this adapter more than suitable for my needs.

I think it might be possible to get enough clearance for my sandwich module by using surface mount chips. I plan to tackle that issue eventually. Fortunately for me only one of my boards has the KBC behind the ISA slots.

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