THIS BLOG HAS BEEN DEPRECATED OK I have done some double triple checking in the doc TM 11-5841-281-12 and it seams that the three displays are independent. Refresh is now almost cake! I will still directly drive the sixteen segment displays via MCP23S17 and some BJT(s). The seven segment displays of each of the three displays are driven via 1x 7443 and BJT(s). The selected display character needs a LAMP TEST, and CURSOR (blinking).
So each of the three displays need some shift registers 74595 now this part has 8 bits each which is nice as I can get 2 seven segment displays per shift reg, but for the 4 sixteen segment devices will need 2 each. So
