The main controller is an old school PIC 16f84 with some simple code to drive the displays from a serial input. The 16 characters are scrolled on input of another character. Extra control codes were also put in to emulate some features of the standard character LCD of the time allowing cursor positioning and clearing the screen.
The PCB is hand etched double layer. The PCB was printed onto laser transparency and exposed both sides before standard etching solution was used. All holes were done on a pillar drill by hand and were tough to align neatly.
A Max232 Serial driver was used to allow real serial ports to connect. Had I done this project today I would have simply used an FTDI usb serial chip and powered the whole thing via USB too.
The power connector is 3 pin with +5v in the middle. This means it was virtually impossible to put the power connector on wrong and blow things up :)
A standard 8 bit shift register was used to get the most out of the limited IO on the PIC allowing 8 bits of data to be shifted in for the character and an address to be loaded on the address pins direct from the PIC. This made the control software a little easier.