What's that? Look like a Wavecomputer 360A mainboard.
Hey, it IS a 360A mainboard! The system bus connector for the 340/380 system is just wire wrapped to the bus lines. The mainboard is populated with 4 generator boards, a stripped-down TONRAM (wave memory) and an IO board with no brain, lacking RAM and PROM.



This is the brain-less IO board of the 340.
There's some minor modifications in the control voltage generation for the master oscillator.
Stay tuned while reverse engineering goes on!



Two RAM boards of a PPG 340B brain unit. Each board features 16kBytes of static RAM, using 32 pieces 2114 RAM chips. One is mapped in the range 0000-3FFF, the other is splitted to 8000-9FFF and C000-DFFF. The latter is connected to the Write Protect switch on the front panel.



While the upper board is a PROM board from the Wavecomputer 360 with four pieces 2708 EPROMs mapped to F000-FFFF, the lower is a board called WA which originally maps 8 2716 EPROMs and 10 2114 SRAMs into the address space, but is modified to allow two 2716 to be located at F000-FFFF as well.
No idea for which this board was originally made, the address ranges neither fit those of the Wavecomputer, nor any of the Wave family.



The wavetable RAM from a 340A. It's the same PCB as in the Wavecomputer 360(A,B), but with twice the memory (8kByte) on it.
Reason: The Wavecomputer has some logic to invert the lower address lines (those making up one "wave") and the data lines of the RAM (2s complement!), thereby allowing for doubling the stored waveforms by making the second half-wave the inverted image of the first.
The 340A does not have this ingenious memory-saving trick, thereby removing the restriction on purely periodic waveforms.
Some address lines are wire-wrapped on this board to make all this possible, but the function is the same as in the Wavecomputer: the CPU loads the waves into this boards RAM which are played back through the generator boards.



Here's the answer why this one has twice the phone jacks than other 340s have :)

the resuscitation continues

8 inch floppy disk could be read with the system data of the 340/380!

Transfer Machine Code

Press "G" for GET FILE on the Waveterm Keyboard.
The Waveterm lists the files on the disk:















MC-FL-EV.BIN is the machine code for the event generator.
Write "MC-FL-EV.BIN" on the Waveterm Keyboard und press return:
















This File is loaded in the Waveterm memory. After this you press
"T" (Transfer) on the Waveterm keyboard:
















Press "0" to select memory, then "2" (system number), then "E" (Event) and press enter:
















The Waveterm indicates: "OK!"
















The 340/380 confirms: "RECEIVE OK !"

Transfer Mode

The system needs two different kinds of data:

• machine code to get the application started
• user data (waves, sounds, sequences)

The original system has a Tape drive assembly.

This is no longer used.

Data can be loaded from the Waveterm A:

• Both systems (Waveterm + 340/380) are connected with the PPG bus cable
• Both systems turn on at the same time (use voltage distributor)
• load the Data Transfer Sequencer in the Waveterm A:

• the 340/380 is on, but not ready to transfer:

• to start the transfer modus press G F380 and then Escape on the 340/380 keyboard:

• Now both systems are ready, in order to exchange data.
• Push "X" on the Waveterm Keyboard: on the screen you see: * READY *
• This is a transfer mode.

380 Event Generator Manual (German)

Inside in the Transfer Sequencer