Olimex development board in a 1970s-vintage Sony 8-track tape player. This allowed 8-track tapes to be played on a computer.
USB Audio Device Class (version 1) was implemented on an Olimex PIC-USB-STK (PIC18F4550) development board. This board fits within the available interior space of the Sony TC-8W tape player used. One limitation of this board is that the analog audio interface is single channel (mono), so only the tape player’s left channel was connected to it. One of the board’s I/O ports was connected to tape player’s standby switch to enable play/pause. Using software tools and sample code made available through Olimex, the USB Audio Device Class descriptors was configuration.
After the project was demonstrated to work, it was disassembled and the tape player repurposed to become the Bluetooth 8-Track Player.