Hello there. I've been searching for this at the forums, but still couldn't find any reply. My LCD1602 is using I2C, and I had no other pins to control its backlight brightness until I got to know that a brightness jumper exists. So I removed it from the module at the back side of the display and now I have two additonal pins to attach them to the Arduino board. I already attached this jumper LED pin to pin 3 of Arduino (for PWM control), but display shows only text, no backlight whatever analogWrite(3, value) I assign. My question is, should I attach Arduino ground to the second jumper pin (also ground) to make it work? It looks like the display consists of leds and when jumper is on it has some, possibly, maximum brightness value, so I try to simulate that "short curcuit" with two wires to make it dim and be controlled via PWM at the same time.
Here is a screenshot if it helps.
Pull the jumper from the I2C backpack (in the blue box). Connect a PWM pin to the top pin of that header and you can control the backlight brightness.
See this thread: Control 1602 LCD I2C backlight with LDR, possible? - #3 by groundFungus
groundFungus, thank you for your reply. I have already done that, but only text appears, no any backlight shown.
I changed the pin from 3 to 9 and it works properly. Thank you.
If your question has been answered to your satisfaction please mark the thread as solved so that other users that may want to help will not waste time opening the thread to help only to find the question has been answered.
groundFungus, I marked the thread and thank you very much for your help once again. I was starting to think that I should use the 2-d ground pin (I mean brightness jumper) to make it work. It appeared that there was a conflict of some kind as I couldn't use the 3-d PWM pin. The 9-th one solved the problem. And have a nice day. I do appreciate your help here.
This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.