Hi, I’ve been working on getting my parallel lcd to work with at little pins at possbile.
Other solutions on the web used the trick to use the shifter output to latch the E pin of the LCD, but the problem is that you have to enable the shifter twice. One to lower E, and one to raise E.
First I tried using separate pins for the shifters LATCH and the LCD E. After refactoring the driver it turned out to be doing exactly the same thing at the same time, so I just connected them together.
By slaving the LCD’s E pin to the LATCH pin of the 8 bit shifter, I save a roundtrip. The cool thing is that I still have 2 pins left on the shifter, and using only 3 OutputPorts.
(EDIT: Fixed some typo’s + explained its working perfectly)