Old PC soundcart

Unfortunately the protoboard collapsed somewhere in 2011 so i am not able to test anymore until a decent PCB is ready again. This schematic is drawn from the prototype:

- The higest address lines of the ISA card are connected to GND

- Datalines D0 to D7 are connected directly

- ISA IO CH Ready must be connected (via diode) to MSX WAIT

- Addresslines A0 to A2 are connected directly

- RESET is connected directly

- Supply GND, +5V and +12V are connected directly,

- Supply -5V has to be added using a 79L05 to -12V

- An extra clock of 14.31818MHz has to be connected to the ISA card

There are a few basic programs to initialize the Plug and Play logic of the soundcard. Legacy cards will work without PNP.BAS.

The inverter and switch are needed to change the addresses. The soundcard can be used in ADLIB mode to make it hardware compatible with MSX-Audio (without samples). Moonblaster 1.4 works fine with it. Changing the switch will make the soundcard compatible with the OPL3 part of Moonsound. The mixer hardware also works, there is no decent software for it yet. If i find some time i should make a good adapter first.

During this project i kept my eyes open for ISA soundcarts at flea markets and radio rallies. I have made pictures of a few cards which worked fine, I remember having problems with the AWE32, maybe it requires real 16 bit communication or some more initialisation. Another reason to start designing a decent PCB, is to replace the hardware switch by a software register.