PS/2 Interace

Over Christmas, I've been writing the software for the PS/2 interface, this will run on an stm8s003f3 
from Mouser, they are an eyewatering £0.67 in the TSSOP package and £0.325 QFN but as I cannot solder QFN by hand it will by the TSSOP. They run at 16MHz which is faster than the base Z80 but the same as final Z80 version based on the Z84C1516FSG.
The Z84C15 is a Z80 at 16 Mhz with the support chips of the KIO(SIO, PIO & CTC) it is still in production. The stm8 and the Z80 will communicate via the serial link at up to 460800 baud, the Z80 side will likely limit it to less than this. If I get around to an eZ80 version that will communicate using I²C freeing up the UART.
The software I'm currently working will drive 2 ports one for keyboard and one for a mouse. The devices I'm using to test are USB via a PS/2 adapter, the genuine PS/2 parts seem to be a bit problematic, it may need a pull-up or pull-down resistor. The source can be found on GitHub in the STM8 subdirectory.
I may could the system down to just 2 USB sockets, they will not be able to drive anything other than a keyboard or mouse. I might get a small board made to help me test the various ports.


Meanwhile building up the ACE3NOKB board continues.

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