Сounter position of the PC mouse

Dear colleagues ! Сongratulation with approaching of New Year ))!

I have troulbe in programming of PC mouse. I need to find the coordinates of the mouse (interface is USB, or PS/2; mouse with a ball inside)
Could you suggest me in programming of this device ? Perhaps, you know code samples in Turbo Pascal or C.

P.S.
Best regards.

There is absolutely tons of info about this on the web

I just googled "Ps2 mouse protocol" and there was pages of the stuff.
Example
**broken link removed**

Pity I work just in Assembler for PIC micros.

https://www.electro-tech-online.com/threads/my-micro-is-conversant-with-the-ps-2-protocol.134700/

Edit to add:

I believe this is 100% accurate. I wrote my software from scratch based just on this.

Bring the extension back to .pdf when downloaded.

Buena suerte.

/Edit

Ian Rogers, atferrari thank you for your assistance.