matze79 - it is nice to see someone actually has time to invest in this. Your efforts are most appreciated. I have a few questions for you.
1) How is the tracking quality of the conversion? A handfull of companies have made these PS/2-to-serial protocal converters over the years, namely Raritan, Vetra Systems, and a few KVM companies. The problem I found with their conversion was the loss of tracking quality, which translated into lagged hand-to-pointer movement, particularly with acceleration, and somewhat jumpy pointer motion. This problem was amplified with increasing screen resolution.
2) Could you do an analysis of tracking quality when using the native PS/2 mouse port and compare that when using your protocal converter on the serial port? Is there any human noticable loss of tracking quality? What about at resolutions of 1280x1024 or higher?
3) As another forum member pointed out, we did have a go at this project from another member in this thread, PS/2 to Serial Mouse protocol converter . This was programmed in assembly using a Microchip PIC microcontroller and would presumably have minimal loss of tracking quality. Unfortunately, only the author was able to get it working. I tried for weeks to get his schematic functional on my breadboard, but failed. I suspect there was an issue with importing the code to my PIC devices, but I could not find any evidence of this. Would you be able to provide the programmed microcontroller chips to reduce this uncertainty? Or will there be a place to purchase the whole kit, whereby the user need only solder the components onto the PCB?
4) Do you have a Logitech MouseMan M-S38 to test with your protocal converter? Although it is a trackball PS/2 mouse, it is the mouse I have been addicted to since '98 and is still the only mouse I use.
5) What have you set your sampling rate at which efforts have you made to optimise this?
As a result of my frusturation from all other PS/2-to-serial protocal converters, I decided to modify several of my motherboards to accept native PS/2 mouse control by modifying the onboad keyboard controller circuit. Reference this thread, Native PS/2 mouse implementation for 386/486 boards using the keyboard controller However, I have only been able to successfully perform this modification on AWARD-based motherboards containing a DIP KBC. Modifying the AWARD BIOS to allow for PS/2 mouse KBC support is rather straight-forward, but not with AMI BIOSes. As such, if your converter contains no noticeable tracking quality at 1280x1024 or 1024x768, I would be very interested in reproducing your circuit for use on my AMI-based boards.