i2c lcd

Other Hardware Displays
1

Hello,

I have got a weird problem today! I made a DMS detector and its worked perfectly. The sensor(mq3) the board (genuino uno) and the lcd (with i2c) are worked , but today the Lcd doesn't show backlight... I can't change wiring , the Lcd get voltage (red light on back), but not shows characters and the green backlight ?! Has somebody got the same problem?

Regards : Dave

2

My hd44780 library includes a diagnostic sketch for i2c LCD backpacks.
It is available in the IDE library manager.
The library is called "hd44780".
Install it using the IDE library manager and then run the I2CexpDiag sketch in the included examples for the hd44780_I2Cexp i/o class.
It will display diagnostic information on the LCD display and serial port.

There is a link in the IDE library manger to the github page, but here is the link to it:

where you can read about the library.

--- bill

3

Thank you so much I will try it when I get home :slight_smile:

4

Ohh, maybe have a bigger problem :frowning:
The yellow led of pin 13 is always lights and the "rx" red led blinks three times, pause and blinks once... com port and programer are correct, but cant upload any sketch.... reset button doesnt work...

5

So this is without anything connected to the Arduino board and just power applied?

What IDE version are you using?
If you have IDE 1.6.8 remove it immediately and get a newer version. That version had serious issues with serial communications and should never be used.

I would recommend that you disconnect everything from the Arduino board and upload the "blink" sketch.
If that doesn't work, something is really broken.

After that connect only the i2c lcd and run the hd44780 I2CexpDiag sketch to check out the lcd and i2c h/w.

6

Yes, just power applied! I use 1.6.12
I've been tried some other IDE version 1.6.10, 1.6.11, 1.6.12, 1.6.13... Try to uninstall and reinstal the IDE completely, but have the same problem everytime. The d13 led lights and the rx red led blinks three times and can,t upload any sketch nor the blink test ...

7

IDE 1.6.13 ??? The latest I see is 1.6.12

What OS are you using?
Have you selected the proper port for the Arduino?

Turn on verbose mode for uploads and see what it says.

--- bill

8

Yes at wednesday got a message that I can upgrade to 1.6.13 :). OS is win7enterprise / 64bit.
I have tried completely uninstall all the showed and hidden com ports in the device manager / reboot pc / arduino plug on and the driver istalled succesfully on COM6... after go to the preferences, port-arduino genuino uno COM6, board-arduino genuino uno, programmer- AVRISP...

But while I plugged on the board, the d13 led lights and any reaction to the reset button :frowning:

I tried to upload a basic blink sketch...the green line running to the end... 3 red RX blink and it writes The upload not succesfull...COM6 is busy!

Ihave been tried som ports...2,3,4,6,10...but everytime the same :frowning: