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Dave, I made three suggestions for modifying the keyboard: Connect the mid point between the reset switches to one of the keyboard drive lines. Add a 21st connection to the mid point between the reset switches. Connect back to back diodes across the reset switches. If I understand your photos, you h...

MEMU-Pi+MTX-Kbd.jpg Some Alpha code. An MTX keyboard being used to type into MEMU-Pi. The keyboard bounce seems to be slightly worse than on my MTX, but that may be due to the surface I am working on. The observant may have noticed the connector of a USB keyboard also attached. That is only used to...

Claus, It is certainly possible to use all 32K of RAM, but their are a couple of restrictions: You will either have to disable interrupts, or install your own handlers for all of them. Many of the ROM routines make use of some of the system variables, so not only can you not return to Basic (althoug...

If you use the fullcpm.bat file as listed, then the games should be on C:.

Are you able to do "dir c:"?. If not, you may need to configure the C drive. If I remember correctly, the command for that is "config b07,c07"

It is not possible to have both a CP/M console, and directly access files in Windows / Linux folders. The CP/M console mode needs to read the BIOS&BDOS from the initial sectors of the disk image. These are not present when accessing Windows or Linux folders. To access the games, you need to moun...

My thanks again to Paul and his wife (sorry, very bad at remembering names) for hosting this, and for the wonderful spread they laid on. Some thoughts that occurred to me during the event (not sure whether I will do anything about them): Tapes: I have for some time wondered whether it would be possi...

Not so very much off topic. A new 80 column capable graphics card would complement the CFX in the same way that the original MTX 80 column card complemented the SDX. For simple, microprocessor generated video is perhaps the way to go. I think it would be possible to do something with a Parallax Prop...

It is a while since I last thought about this in detail. However from what I remember: Assuming that the video memory is all in one chip, then the address bus on that chip is in contention whenever the display is being refreshed, and the CPU is also trying to access the video memory. I have in the p...

Simple scrolling is not necessarily slow on an I/O mapped display. On the MTX 80 column card it is a simple update of a 16 bit register on the 6845 controller chip. Indeed during fast scrolling you can see the occasional glitch when only half of the register has been updated by the first of two 8-bi...