Quoted from zacaj:The blanking circuit I don't quite understand either :/ I think it's some sort of one-shot timer. When the MPU starts the display update process it enables all the display output chips using that common vertical line on the left, and part of that triggers the blanking circuit at the bottom to send out a timed blanking pulse to the displays, turning them off momentarily, and during that time the MPU sends new data?
Yeah - the MPU is telling the displays to latch on to the data they were given. Then, in the next cycle, the displays have to be reset, so the blanking line pulses, dropping the latches on the displays, for the MPU to re-send them data. 
