Hi,
I recently visited a guy in Melbourne who sells Goteks for CPC with bluepill boards that have on screen displays as per this video:
https://www.youtube.com/watch?v=9noYsB_QJkQ
What would be involved in making an Mx4 card that whatever desired text could be sent - I am thinking such as... debug info in a program with debug info enabled, task or song info in background tasks - and other uses.
https://www.msx.org/forum/msx-talk/hardware/flashfloppy-osd-is-now-available-on-msx
does anyone have that Amiga font in ttf/otf?
Well... The OSD with the FlashFloppy or the HxC firmwares are already available on CPC since few years now. it overlay the display by using the Csync and Green signals to display de drive directories informations. No need to have an extra "blue pill" board: https://hxc2001.com/docs/gotek-floppy-emulator-hxc-firmware/pages/addon-on-screen-display.html
Now, using an extra MPU chip allows more feature than the gotek itself can do. (better resolution, more colours, scrolling effects, ...). But sure, if you do it for an external expansion that in/out the video signal, you can overlay customs informations too.