Just came across
Vince Briel's version of
markadev's Apple II VGA card and I'm wondering if it might allow me to add Apple II video text and graphic modes with VGA output and run Apple II software on a homebrew 6502 SBC?
Quoting from markadev's github page;
Quote:
This project is a VGA card for Apple II computers to ouput a crisp RGB signal to a VGA monitor instead of having to rely on the composite output. This is accomplished by snooping the 6502 bus and creating a shadow copy of the video memory within a Raspberry Pi Pico, then processing the raw video memory contents to output a "perfect" signal.
The card connects to the 16 address lines, 8 data lines, the DEVSEL strobe (16 slot dependent addresses), the R/W line, and the PHI0 clock line. I'm wondering if I could map the 4K $CXXX block for I/O on an SBC, provide a DEVSEL strobe, and read or write to Apple 'soft switch' addresses in order to implement Apple II video using Text1, Text2, Hires1, and Hires2 areas of main memory? What do you think? Could this work?
TIA... Cheerful regards, Mike