I'm mainly working off of the specifications document by the NAMA people located at http://www.vending.org/technology/MDB_Version_4-1.pdf

Pinout:

GRN 6 MCommon 3 NC RED 5 MTX 2 0DC BRN BLK 4 MRX 1 34DC WHT

Serial Communications:

9600

1 start bit, 8 bits data, 1 mode bit, 1 check bit, 1 stop bit

check bit

• drop carry byte, address+all data bytes.
• A checksum will not be performed on ACK, NAK, or RET bytes.

mode bit-

• from vmc sets if byte is address
• from slave if last byte of data (or finished talking to master?)

transmit nrz

receive inverted

Misc:

"Each peripheral should be polled every 25-200 milliseconds. This can be done by

the POLL command or any other appropriate command."

Mtx need to source 100ma in order to drive optos!

Connectors:

Vertical Header: Molex 39-28-1063 ~1.25 on digikey

Right Angle Header: Molex 39-30-1060 ~1.25 on digikey