Although this is slated for a bigger upcoming project, I figured it would likely be useful in a stand-alone application as well. Since I have a new compact motherboard design that will require an internal mouse interface with the ability to easily switch between joystick ports, and if desired completely disappear (stealth mode), I began work on a new mouse interface chip for the A8. It could have just as easily been used in an Atari ST, or with a bit of code finagling also made to work in an Amiga. Initially I looked at some of the GPL PS/2 mouse-to-ST/Amiga offerings, thinking that I would simply add what code I needed. However once I dived in, I quickly decided this would not be a good way to go, and so began my journey to write mouse code from scratch in my favorite development application FlowCode. Anyway suffice it to say i am probably 85% done, with the last 15% dedicated to supporting mouse movement acceleration (very tricky stuff).
So here's a look at how this new mouse chip will be implemented in my new project, along with of course a TK-II keyboard chip (this schematic shows part of the I/O section).
Unlike the mouse support that existed on the early versions of TK-II firmware, and then was later abandoned, this one has true ST mouse emulation as its primary goal (plus some enhancements). Yes I know people would love to have a USB mouse instead (as well as a USB keyboard interface), but with all that I have going on I'm afraid this is the best that I can presently do. Especially considering the learning curve required to implement this in USB as well likely needing to switch over to a different processor family to really do it right (yet another learning curve to climb). Besides despite what the rumors would have you believe, there are plenty of NEW PS/2 mice and keyboards still available, as well as some that offer wireless support. And lets face it, PS/2 protocol is a hell of a lot easier to work with. Ohh and did I mention that I get lazy from time to time .
Anyway I doubt if I'll be making any PCBs for stand-alone plug-in usage, but if someone is ambitious, I will be providing the PIC MCU Firmware (in JOY2PIC and Microchip file versions). Stay tuned for more info and eventually the firmware release.
Edited by mytekcontrols, Sun Dec 11, 2016 10:47 PM.