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Posts: 4
Firstly can I say what a superb piece of work this is.

I have two questions.

1. my LED's are so dim they are almost not visible when they are on. Other threads I have looked at seem to suggest that if you exit and restart Mobiflight is should sort itself out, mine still stays dim. I have also tested the board to ensure it is working with no issues found. This is using an Arduino uno. Any ideas?

2.With reference to the PMDG 737. Using the Offsets such as landing gear below

6570 3 BYTE MAIN_annunGEAR_transit[3]

6573 3 BYTE MAIN_annunGEAR_locked[3]
How do you set the Annun for each gear ie nose left and right?
2018-11-05 09:01
From: EDDG, Germany
Posts: 1004
Hi bob.little,

welcome to MobiFlight!

Well, if your LEDs are too dark, this can have several causes:

1. you have taken cheap LED, which have a small light value (mcd). Let's be on the way that LED should have for a DIY cockpit from 8,000 mcd. This has the advantage that they can be considered more individually in light intensity to the personal taste. Another advantage is that they are not to operate with 20mA / LED, but with considerably less, and yet sufficiently illuminate the surface to be illuminated.

2. the resistors of your LED are too high. The 5V operating voltage for Arduino MEGA is typically sufficient for 470 ohm series resistors. If using the high brightness LED mentioned above, resistances between 680 and 1000 ohms are sufficient.

If, on the other hand, cheap, low-luminance LEDs are used, the resistance values ​​mentioned by me lead to dimly lit LEDs. In such a case, you can try to either reduce the series resistors (150-330 ohms) [not recommended because too much power is consumed] or replace the LED with high brightness LEDs and adjust the desired brightness according to the resistance value.

Another important aspect is that the Arduino UNO is no longer supported. It is therefore recommended to upgrade to the Arduino MEGA 2560 R3 (or a clone of it). The MEGA will continue to be fully supported.

Regarding your offsets in terms of gear, the PMDG should note the following:

If you look at the offset label, you'll see a [3] behind it. This means nothing more than that this offset is present 3 times.
once for the nose landing gear, the right main landing gear and the left main landing gear.
Accordingly, each 1 byte size. The reading is as follows:

6570 1 byte MAIN_annunGEAR_transit NOSE (red LED)
6571 1 byte MAIN_annunGEAR_transit RIGHT (red LED)
6572 1 byte MAIN_annunGEAR_trasint LEFT (red LED)

the same for the locked ones:

6573 1 byte MAIN_annunGEAR_locked NOSE (green LED)
6574 1 byte MAIN_annunGEAR_locked RIGHT (green LED)
6575 1 byte MAIN_annunGEAR_locked LEFT (green LED)

With Mobiflight, you need a configuration for every single one of these LEDs, which is referenced to the respective offset. Try it, it should work right away.

Please report here if it worked. I wish you success!
2018-11-05 09:58
Posts: 4
Thanks for the speedy reply.

Its a steep learning curve for someone who is not used to anything other than plug and play but good fun all the same.

The LED's work at full brightness with other applications using a 220ohm resistor so I can only assume it's the Uno board. I will purchase a 2560 Mega and let you know how it goes.

Thanks also for the information ref the landing gear indications.

Best regards
2018-11-05 14:15
From: ETSI, Germany
Posts: 1980

Just to prevent a missunderstanding.... Do you try at the moment to wire 3 LED ( the 3 Lights for nose, left , right) to ONE Pin, cause you not know how to split it before stephans comment ?

Sure... If you wire 3 LED in row with one resistor to one Output Pin.... then Brightness will be not the same like in a correct "1LED=1Pin" Logic !
Good Luck !
2018-11-05 20:51
Posts: 4

Thank for this.

No, I wired 1 LED to one resister and to 1 pin, that much is the same as link to fs that I have previously used. I have ordered an Arduino Mega and if it arrives in time I will give it a go over the weekend. Hopefully, that will put this issue to bed.

Thanks very much for the advice
2018-11-08 17:00
Posts: 4
New board arrived. all is now working as expected.

Thanks very much for your help / advice.
2018-11-09 17:37