Bitsavers has some PDFs about Foonly microcode.
Activity
larsbrinkhoff commentedon Jan 8, 2018
Looks like a microcode listing for F4:
http://www.bitsavers.org/pdf/foonly/f4/F4uCode_Mar84.pdf
larsbrinkhoff commentedon Jan 8, 2018
F2 and F3 microprogramming manual:
http://www.bitsavers.org/pdf/foonly/f3/F2_F3_Microprogramming_Dec81.pdf
larsbrinkhoff commentedon Jan 8, 2018
Also 6502 ROMs from the F4 frontend.