After I had established I could get the current state of the console draw-stops, the fun and games with the main board started. There is a lot happening on this board. It handles all the input boards (a maximum of 6 at the time of writing, each with 64 inputs). It also issues instructions to the digital sound processing devices. It also manages a 20x4 line LCD display and the audio processing and routing.
Here is a digital sound processor device being evaluated.
This was a real voyage of discovery for me. I had to learn about the I2C interface that this device uses. This is essentially two control lines - one for data, and another for clocking the device.
That's what this particular set-up is trying to establish. Luckily, my programming environment shields me from a lot of the intricacies of the I2C interface!
The digital sound processor (x2) now on the main prototyping board, with one of the completed input boards patched to it.
A different angle to the previous shot.
The front of my desktop computer is off by the look of it. Maybe I had an issue with it at the time - can't remember!
A slightly closer view.
Found a use for the solder bobbin as an acoustic resonator!
The bread-board that had the sound processor on it, has now given way to some power supply components, including hardware controlled "brown-out" shutdown protection.
The sound processor devices need their own dedicated 3v supply.
One last look at the processor prototyping, this time from an end.
The black plastic article, seen nearest here, is a pod containing the microphone amplifier/battery.
The finished, assembled processor board, with all but the audio amplifier device in.
Notice a bit of a cock-up by me on the board design around the top right (had to deliberately leave an IC leg out of a socket)? That's life I guess.
A final look at the processor board.
Believe me, the main heat-sink does have to be this large, as it can run pretty hot. More so when driving an LCD display with a back-light.