Theatre Organ Combination Action System

I started out with 3-Devtronix 221-2 Capture Action motherboards and 40 221-3 daughterboards. They operated perfectly, however there weren't enough of them, so I started designing.

The first design was a new daughterboard. Technology changed since the old boards were designed. The 16x4bit RAM chips are still available but lost memory when power waas removed, so I decided to use a 2K x 8bit SRAM that included a battery in the chip. The old motherboard is limited to 16 pistons but I wanted 16 generals as well as 8 divisionals. The 2K x 8 SRAM has enough additional address lines to provide an additional 16 Piston inputs as well as 256 Program Selections (each Program stores all the stop data for all the pistons for that Program).

This photo shows the system with the motherboard, controlboard, and 5 daughterboards.
This is the new daughterboard. The PCB design is in gerber format. The PIC program is designed to not pulse a SAM that is already in the proper position. If a SAM needs to be operated, the program will turn off the SAM magnet once the SAM has moved. Another program is available for those SAMs that seem to bounce back.
PDF of Daughterboard Layout

Daughterboard Assembly Document
ZIP of Gerber Files

HEX file for PIC program


Assembly source Program File (Only for reference)
This is the new control board. The PCB design is in gerber format. The control board accepts up to 32 piston inputs (ground the input to activate the control), 1-Cancel input and 1-Set input. All inputs are optically isolated and powered from a common 5V supply.
The control board outputs are compatible with the daughter boards shown above and also compatible with the older Devtronix daughter boards.
PDF of Controlboard Manual (with layout & schematic)


ZIP of Gerber Files - This board is 6.5" x 3.4"


HEX Program File


Assembly source Program File (Only for reference)

Motherboard - This has 14 sets of connectors for 1 controlboard and up to 12 daughterboards. (13 daughterboards if you leave off the left terminal block)

Motherboard Parts List


ZIP of Gerber Files
This is a single-sided board even though the gerber files show 2 sides. The top (front) side is blank. The board is 11.5" x 6". Use GC-Prevue to see the contents of the Gerber Files.
This shows the new daughterboard plugged into the old Devtronix motherboard. One of the older Devtronix daughterboards is plugged in for comparison.
This photo shows the interconnect between a stop switch and a stop board. Note the board with all the connectors that I am using so I don't have to solder the stops switch directly to the stop board.
This is one rank all wired up and working. (Only the general pistons are connected, the divisionals aren't there yet)
Just a view of a bunch of wired stop switches.
This is a simple board used to redistribute the sets of piston buttons (1 ribbon cable per set) to the appropriate stop control board.
This card frame contains the midi boards for the stop switches (grounded input = midi note on) - there is one ribbon cable per ctop switch card.
The card frame also contains the midi keyboard scan boards for each keyboard (+15V = midi note on)
The MIDI outputs the go to MIDISPORT 4x4 modules for input to the computer.