I bought these boards after a few beers about 2 months ago, they took a while to arrive from the US, but I managed to to wire up the processor board last night, work out the power and how its reset line works, its quite bizarre. They use an opto isolator powered by a seperate 8v line from the power supply to trigger the reset circuitry on the processor board. This is going to be another keyboard to rackmount coversion.
This may be of interest to any AX-80 owners with faulty displays. I’m recreating an AX-80 in a rack mount format and wanted to emulate the VFD displays in OLED format, now ideally I would have used 256x64 pixel 3" SPI displays, but I don’t have room on my from panel for those. So I’m using dual 0.96" 128x64 displays side by side. I did some testing with a Pico but I could not get interrupts to work for the life of me, so I thought I would try a SAMD 21 based Arduino that runs at 48mhz. A bit wasteful and probably cheaper to use Teensy 4.0 boards. But anyway tonight I was sorting of successful in creating bars for the display. I need to code some more to get it looking pretty, but I’m happy with the results.
So finally my filter chip adaptors arrived from the states and I got them installed today and this is the first power on and sound from the working AX-80 synth. I need to add a mute circuit and the phones/output circuit. But as a test I’m happy.
