Also note: If you’re powering of the 5v pad, that will only be powered by battery. the 4v5 pad will power off battery or USB.
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@Yuri_Rage do I have to change other serial port to non gps value and only serial 3 should be gps?
Right now I have connected the rxand tx4 which is mapped to serial 2 I believe.
But why no compass is showing up in compass page ! it’sI2C right?
Then you need to set SERIAL2_PROTOCOL=5 and then, for good measure, set SERIAL3_PROTOCOL and SERIAL4_PROTOCOL each to -1.
There’s no compass because you don’t have SCL and SDA connected.
No. I have connected the purple and orange wires to SCL and SDA respectively. It is in the attached pics.
also I have set the serial 2 to gps. Let me disable the other ports and check
Double check your solder connections. They look suspect (cold and crappy).
Attach a copy of your parameter file.
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This brings back memories, but unfortunately not all the memories haha… I recall that one of the boards I was experimenting with at that time had differences between the serial port number in arducopter and the ID number of the TxRx pads in the pinout. So I I connected to a pad called TxRx4 but I think this actually corresponded to serial5 etc.
That’s SERIAL2, which can be configured as a half duplex port for RC telemetry. If you mis-set BRD_ALT_CONFIG or the serial options, it won’t work for normal UART comms. And it’s why I want to see the param file for the current issue.
You should follow the wiring diagrams and defaults. They aren’t chosen at random, and doing so will avoid these issues.
You don’t have to apologize for delaying getting your own help 
You don’t have serial 2 set up for GPS.
Set the following:
SERIAL2_PROTOCOL,5
SERIAL3_PROTOCOL,-1
SERIAL4_PROTOCOL,-1
As for why no compass is detected, I don’t know. Check the soldering again and make sure there’s a good connection and that there’s no bridge between SCL and SDA.
this is working for GPS now and compass is shown suddenly and now it says missing
new parameter file
f405_crtr.param (18.1 KB)
Power down, power back on, and reconnect.
As you said connected the GPS in TX1/RX1 and GPS is working like a charm! but still no luck with my compass. it showed and went missing.
After reboot it didn’t turned up.
resoldered the pads
Intermittent operation indicates a hardware issue. I still suspect a poor solder joint, but it could be a broken wire, bad pin, or bad component on either the compass or autopilot itself. Hard to diagnose without having physical access.
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Hey guys… as @Yuri_Rage said problem got isolated with faulty hardware. I used a new m9n gps unit to isolate it.
thanks a bunch guys.
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The big lesson learned is: read the documentation. Manufacturers aren’t beholden to screen print label standards, but ArduPilot enforces a certain consistency in hardware pins, so you MUST reference the manufacturer data and ArduPilot wiki.
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guys new, issue. now after few days i tried to power up the whole drone
- checked the connections and soldering to the GPS unit!
- all other soldering are good and intact.
but the GPS module has a multicolor led (mn9) which is not glowing in power up sequence, also when connected to MP it says no compass found. but i get a GPS fix (GPS fix LED blinks) after some time. is this related to some booting the sensor after fc power up time?
Could be. Hard to tell with so little data.
What other data will be required?
- .bin log file with LOG_DISABLED activated.
- Is a compass detected?
- Have you already set BRD_BOOT_DELAY to 2000?
- Is the GPS_TYPE correctly set?
- Does the FW support the compass? ← custom.ardupilot.org
- What FC is this?
- Which FW version?
- Parameters
f405_crtr.param (18.1 KB) - No compass was not detected (that is the whole problem, this setup worked earlier as per the discussion but now after few days of troubleshooting. I tried booting the board with flight battery but compass was missing.
3,4 and 5 this was working already - Mateksys F-405 CTR
- 4.4.4