Good day all,
I have a Due that I am driving a Nokia 5110 with, no problem. I then added a couple of pots to the circuit connected to two analog pins, again no problem. Then I added three push buttons, thats when I get problems. Push any of the buttons and the LCD blanks. Turns out when I hit the push button the RST line to the Nokia goes low. None of the other lines are affected just the RST line. In the attached schematic I show the three buttons connected to D51-53 thru to ground with a resistor between. I have tried this with a 10K resistor and a 200K. I have tried configured D51-53 as INPUT and INPUT_PULLUP I also turned it all around and connected the buttons to the 3.3V with a resistor to ground and the line to D51-53 off the bottom of the switchs. Nothing works, I hit the switch and the LCD blanks due to to RST line going low. I’ve checked my wiring, there are no accidental shorts. What the heck is wrong?
Good day all,
What’s the purpose of R3, 4 and 5?
Actually I tried without them first, but then I thought maybe I was drawing too much current, so then I tried the resistors
How about a pull up resistor at that reset wire ?
Nice idea but it did not help. The lcd, pots and switches are all mounted on a perfboard. I tried disconnecting every wire but 3.3, GND, and the LCD wires and still pushing the switch causes the RST line to the LCD to drop to 0. Either there is a flaw in my circuit or I have miswired the perfboard. I have scanned the board multiple times and don’t see anything wrong. Can someone confirm the circuit is sound? Then I can concentrate on the bord.
I think I have it. I was using a DSUB 15 cable to connect things...except it was not a plain straight thru cable with DSub 15 connectors, it was a VGA cable which is not a plain 15 wire straight thru cable as I was assuming. There are a bunch of common wires in the two VGA cables I have tested. Arrgggh