LCD empty with MobiFlight

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1

I have some LEDS, buttons and switches working earlier but I’m having a problem getting the LCD 16x2 to display anything.

I have added connected an LCD device and tested in the Arduino IDE.
In Mobiflight I set a new device for an 16x2 LCD with default address: 0x27 (not sure of this address?)
Then in Config Display I have chosen the LCD Display, entered some hard coded text for the two lines in the little LCD box.

I pressed the Mobiflight Start button while in the sim - however in the sim it shows nothing on the LCD?

Any ideas? How do I set a few simconnect variables instead of hard coding?

2

Do you see a message from MobiFlight when you first power up the Arduino before running the sim?
If not you could try and upload the configuration to the module again. My 16x4 has the address 0x27 and displays “MF wishes Happy Holidays!!” at power on.
After this, in the 'Display" tab, you can press test to see your text, again before running the sim.
If nothing is seen you can try and adjust the lcd contrast by turning left or right the potentiometer on the back of the lcd module while running the above test. If still nothing, then I can only think of checking the wiring of the lcd module, but I expect you have already done that.

3

I had this exact problem and found the contrast control on the I2C board was turned way down. Turned it up and presto it was working.

4

Thanks, I got a feeling this could be the issue because I see clearly the light color boxes for the text, and so the text could be masked.

I am using a circuit design without a dial (rotary encoder). Is there a way to change the contrast in code or do I need the dial for that ?

Also, Fyi - I am going to order another LCD with “I2C” so the wiring is easier.

5

It a small pot on the back of the I2C board. Normally blue and square

6

sounds definitely like the contrast adjustment that you have to with the pot on the back

7

I tried again last night. I added contrast adjustment dial. I watched the youtube video by 737diysim. I am choosing a Simconnect variable and see an Output value in the table. But no display is seen on the LCD as of yet. I am not sure why, because I see text in Arduino program. I will order some more LCD’s with the I2C.

8

Does your LCD have an I2C adapter? What address are you using?

9

When you configure the module via mobiflight, you should immediately see a message displayed, normally it’s MobiFlight Rocks!!! but at the moment it’s MF wishes Happy Holidays!!!

10

So is the LCD module you are using now the parallel type interface i.e ~16 wires? I don’t think MobiFlight works at all with this type and they also do not have the contrast pot built in that we all mentioned. When you get the I2C (just 4 wires) version let us know how it goes, it should be quite quick to get working.

11

Yes I am using that one. Can anyone confirm the above that the 16 wire LCD 16x2 does not work with Mobiflight? I have ordered some new LCD’s but it takes time to ship to here.

12

Correct. You need the I2C interface. You can buy the I2C card for $3. I bought two and removed the headed and installed the I2C on the 1602. But, I have been building PCBs for 20 years so maybe not the best way to go for you.

13

Electrical side - just learning here. Coding is fine. It’s just figuring out the hardware and wiring that’s a challenge.

14

Once you get the first one working the rest will be soooo easy. You will wonder why it took so long the first time. :smiley: