I made it once and disassemble it. I bouht neat case to assemble it all over again but now for good.
I expirienced some problems with LCD. First is barely visible. It took me half of a day to doublecheck wiring… then i connected other lcd i had and result was differend. It was a tittle bit brighter when i turned potentiometer maximum to the side - but still it wasnt as bright as first assembled.
LCD 1602A
Had no problem at same powersource before at same lcd
One is the backlight which is powered through pins 15 and 16 and affects the blue background.
The other is the 'contrast' which is controlled by the potentiometer via pin 3 and affects the white characters.
Have you checked to make sure that there is a series current limiting resistor for the backlight on your pc board? If not you may want to try a external one in series with the connection to pin 15 or 16.
Determine what happens when you turn the potentiometer from one end to the other. The characters should disappear toward one end of the potentiometer range and get very bold toward the other. The optimum setting is near that 'bold' end.
Hi. I menaged to find problem and fixed it. It was a wiring! But it only solved half of the problem. One LCD works better and seccond still is barely visible... Wonder what coses that.
One is the backlight which is powered through pins 15 and 16 and affects the blue background.
I don't know. I''ll attach photos so you can tell me if i need one (I hope). I'm rookie at this stuff.
Your code and your wiring is obviously correct if one of the two displays functions properly. I am going under the assumption, not completely clear from the photographs, that you are using the same setup and just swapping the displays.
If that is the case then the most likely problem with the 'bad' display is in the soldering of its header pins to the pc board. Try reading this for some pointers on soldering.
floresta:
Have you checked to make sure that there is a series current limiting resistor for the backlight on your pc board? If not you may want to try a external one in series with the connection to pin 15 or 16.
In the photo he provided in his original post it looked as if the very bright backlight was washing out the display making the characters appear dim by comparison.
