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trying to figure out what RE and EN leads are...yes backlight works....and the raduino?worked flawlessly till I started tinkering....

On Jul 14, 2017 8:08 PM, "Arv Evans" <arvid.evans@...> wrote:

Curt and David

I get that when the Arduino has not fully initialized the LCD display.? It can be caused
by the RE or EN lead not making good contact.? I have this sometimes when using a
prototype plug-board for temporary layouts.

Is there any back light on in the LCD?? Has it ever worked properly?? Does the tuning
adjustment work??

I doubt that this is an LCD problem or a problem with software or the Raduino board.?
Most likely it is a wiring situation...but I have been wrong before.

This is what happens when power is applied to the LCD but no subsequent commands
are sent to the display to initialize it for 2 lines by 16 characters.? I made this happen

by lifting the LCD's RE lead from its connector.

There are 2 control lines (RE and EN) along with 4 data lines (D4,5,6,7) sent to

the LCD.? There are also +5V power and ground on the two pins on one end.? The

two pins on the opposite end need +5 through a small resistor and ground for the

backlight LED.? A look at the schematic for the Raduino will show which pins connect

to what between Raduino and the LCD.

?

It should look something like this, but with the normal Radiuno text on the LCD.

?

Yes, I know those are poor quality pictures, but its the best I can do with sunlight

streaming into the room.?

The contrast control potentiometer can change whether the boxes are shown as
black or white on the back light background.

Arv
_._

?

On Fri, Jul 14, 2017 at 2:01 PM, Curt M. <Kc3hjp@...> wrote:

Have any of you guys seen this where the display shows black boxes all the way across the top line of the display?