Контроллер BDI для фирменного Sinclair ZX-Spectrum - обсуждение

[MV1971]

TR-DOS on +3/+2A/+2B computers can work, but BDI must detect actual state of ports 7FFD and 1FFD.

Now I detect only bits 4 and 5 7FFD, and bits 0 and 2 1FFD.
Hardware allows to detect all bits.