first of all I am new to this so please be gentle with me
Secondly what I would like to achieve is to transfer MAVLINK data between Cube Orange and my PC over Microhard pMDDL2450 radio module.
I have managed to configure radio modules for serial transfer so with this I have no problems. I am aware that Cube serial is TTL level and Microhard is RS232 level so I am using RS232/TTL shifter in between. This connection is working as I connected a GPS module with TTL output directly (trough RS232/TTL shifter of coarse) to Microhard radio serial and I get the data on the other end (with Microhand connected to PC over USB to Serial adapter).
The problem is I can’t seem to get the data from Cube Orange GPS2 serial port (or any other serial port besides serial0 (USB)).
So first of all I would like to clarify if I made the correct connection. All I could find about port pinouts was this site: https://ardupilot.org/copter/docs/common-pixhawk-overview.html. So I used this section as if understand correctly GPS2 is on serial4:
SERIAL 4/5 port - due to space constraints two ports are on one connector.
| Pin | Signal | Volt |
| 1 (red) | VCC | +5V |
| 2 (blk) | TX (#4) | +3.3V |
| 3 (blk) |RX (#4) | +3.3V |
| 4 (blk) | TX (#5) | +3.3V |
| 5 (blk) | RX (#5) | +3.3V |
| 6 (blk) | GND |GND|
With connected TX, RX and GND.
Next I connected Cube to PC over USB cable and opened Mission Planner (MP) to set the serial for MAVLINK. So I’ve set SERIAL4_BAUD 57, SERIAL4_OPTIONS 0 and SERIAL4_PROTOCOL 1. Then I also set the SRn parameters (I copied what was in SR0 to all the others as I know serial0 is working fine and I get data form it). I know how SR parameters are working regarding serial interface, but as I was experimenting with different serial ports I set them all to SR0 values. Now as far as I am concerned this should be all I need to do or am I missing something?
Next thing I did was to connect the Cube to PC over TTL to USB adapter (which I first checked with previously mentioned GPS to confirm it is working) to see if I get any data out. Opened the serial port with Hercules Setup Utility to see if I have any data flowing in. And I have no data coming over to my PC (If I connect to MAVLINK port with Hercules I get data out so it should work). Then I tried to connect to same port with MP and had no luck also.
As I didn’t get any data out I tried swapping RX/TX pins. Both physical and later with SERIAL_OPTIONS. I tried setting RX/TX PullUp. Nothing resolved the issue.
Also tried everything with GPS port (serial3) as I connected GPS to it and I know the port is working.
And this is where I am stuck. So my questions are:
- is the pinout used correct?
- are the settings OK or do I need to enable anything else?
- do I maybe need to initiate MAVLINK data stream with some command (what I learned in the process setting SR parameters should do that, but I might be wrong)?
- I am wright to assume I can connect to Cube with MP over other serial ports, besides serial0?
- what else can I try? Any guidance would be helpful.
- what am I missing?
Mission Planner version used: 1.3.72 build 1.3.7463.24854
Cube firmware: ArduCopter V4.0.3 (ffd08628)
Thank you all in advance.