I have been fighting to get my dual display board to function. The first attempt was to use a 50-pin breakout board: FAIL; The second attempt was to pin the ICs to the connector which is an IDC male with a notch (upper-left 1, lower-left, etc. FAIL; Third and final attempt worked! I said the heck with their number scheme. So I went with an old standard row 1 upper-left pin 1 - 15; lower-right pin 16 - 30 which is now over pin 1. So without further eloquence here is the 30 pin header interface listed by IC pin number:
|5||RST!||RED||28||25||No Pins 23 through 26|
|No Pins 7 through 10|
I will also use Arduino Mega pins 50, 49, 48, 47 53, 52, 51 for my two switches, using three-bit BCD code and pin 46 for the switch interrupt. I generate the interrupt by using a quad input or-gate Priority Encoder whose output EO goes to a Schmitt Trigger to actually signal for the interrupt. I got the 15 pins by 2 rows with Wire-Wrap tails from Samtec as samples.
Below are a few snaps of the test harness. Without the PanaVice with the PCB holders, this was a daunting task as you have to work on both sides at the same time. I also tried my 3M/AP Products TC-48 which never made contact with the pins, as it was made for plastic or ceramic parts that have different geometries but still fit the normal pin spacing.