MobiFlight Community Support

Hi all,

I bought a display module with Maxim MAX7219 CWG 1708 IC. I am trying to set an output for Speed IAS to a 8 digit module.
a) 5V and GND as tutorial in mobiflight tutorials;
b) DIN = 30; CS=32; CLK=34

My problem is that mobiflight keeps saying "1/29/2018 12:34:35 AM(929): Error on config execution. Input string was not in a correct format." as soon as I try to Run the program.

It seems that the configwizard window it a bit diferente from the one shown in the tutorial.
I configured as the tutorial and when press the "Test" button some stange symbols are shown in the BDC. The BCD should display "12345678".

What can I be doing wrong?

Thanks Carlos.

Here is the link of my module.
https://produto.mercadolivre.com.br/MLB-915693397-modulo-display-8-digitos-de-7-segmentos-max7219-arduino-spi-_JM

It is a Display odule MAX7219 arduino SPI...
Is it compatible with mobiflight?

When I change the speed in the simulator strange things happens in the BCD display...

Thanks
Carlos

Good morning all,

As I bought 3 of them I tried to use another one to check for possible problems.
The second one just shows 88888888 in all digits.
If you "Test" it wont show anything else.
I weld the pins that come with it and used a protoboard to make the connections.

Tried to change from IAS to Heading and I get the same.
If I restart everyhing (Mobiflight, Arduino) it is the same problem.
I turned on the log and it seems that mobiflight is sending the correct info to the module.
1/29/2018 7:18:39 AM(708): Command: SetModule <1,0,0,036,224;>

Mobiflight get the correct value from the simulator, but it seems that the Max7219 does not understand.

Any help would be appreciated.
Thanks.

Hi.

Please tell me WHAT do you mean with BCD Display ??
BCD is short for "Binary Coded Decimal" .... This have NO context to the Display..... This only tell us that the value of Offset is not Decimal... Its Binary (BCD)
Please not use the word BCD in combination with the Display to prevent confusing !

*****

Basicly the tutorial is show correct information..... Only difference from this old Mobilfight version to current system is the "Multiply" field.... this not longer exist and is now the "Transform" field.

The error warning pretty shure occures cause you set "1" in the transform field (instead of 1 in the old Multiply field like in tutorial) ... Here a simple "1" occure in a syntax error !

The second thing that is not shown in tutorial is the needed compare ! The Offset only show a value without "leading 1" means a Frequence of 123,45 is shown as 2345.
To solve: Please change input in "Transform field" from "1" into "$+10000" Then all sould be fine !

Please report experience !

Postings are overlap !

About second problem.....

These cheap chineese Displays often have a building issue..... The Connectors on the Left and right "can" be broke ( whatever they look good)

In your situation there can be two reasons....

1. Missing contact.... MaxModules are NOT build to wire them with a bread board improvisional.... A little moving of wire occure in a error..... and then Arduino and Mobiflight must restart to work again. It´s HIGH recommend to solder the wires at all time ( or you use professional connectors like "dupont" !

2. broke Board..... Maby 10-20% of boards are broke when you buy it..... here the Pins on the left/right are not correct soldered. Simply resolder it again yourself. Just get a drop of thin into the holes.... Keep up you do it perfect and not make cross contacts !

Thanks,

I am using IAS speed to test.
I am not using any Transform calculation or compare settings.
I tried the 3 display modules that I bought from a store that sells Arduino stuff here in Brazil.
The 3 displays modules have the same behavior.

I connect the arduino into the usb port.
Then I run the Mobiflight.
The display shows just eights (88888888) and nothing else.

Thanks.

As i told....
The 88888888 is a sign for a wrong contact or better for a wiggle contact.

Please note.... the Display must be connected to the Arduino BEFORE you power it up. If you set the Display while Arduino is running ( On USB ) then it can´t work.... The Display must be initialised by the Arduino !
So if you make a improvisional setup with only jumper wires in the solder holes then a millisecond wiggle on wire can cut the contact and THEN the Display is not initialised and stop working (show 8888888)

I recommend for testing : Solder the Pin Headers (1x5) on each side if they are not already soldered there. Then connect your Display to the Arduino with professional connectors (Dupont) or with Male/Female Jumper Wires. NOT simply hold or glue the cables or use breadboard !
You can improvisional solder it just for testing BUT the contact must be 100% correct !!!

Finaly get shure you restart your arduino ( reset button or reconnecting on USB ) after you set the display and before you do the testing !

Thanks for your help,

In fact I am using Dupont connectors from the arduino to the protoboard.
I weld a 5 pin connector in the display module (this 5 pin connector comes with the display module)
I connected the display and then I reseted the arduino pressing the reset button of it.
Arduino initializes and the display show only 8´s.

I checked the welds and they seem to be ok.

I am going to upload a small program to the Arduino to test the display. I will post the result here.

Thanks

I think there is an issue here with my arduino board.
I uploaded a project directly to arduino that works with these displays modules.
This project displays several digits and perform a small delay.

Still nothing happens. Now the 8´s do not appear but sometimes some junk or digit flashes.

How can I make a reset to the arduino to restore factory settings?

Thanks.
Carlos.

Hi pizman,

The problem is solved!
My Display module is working perfectly. The problem was the VCC Dupont cable. I changed the cable and worked ok.
Thanks a lot.

P.S. If you can, please add [SOLVED] to the title of this post and change the title to "Display module MAX7219CWG problem".

Thanks again,
Carlos