I just received the 3DR Radio V2 along with its cables but I’m stymied at connecting it to an APM 2.4-series board. I’ve read this page but it shows an earlier, larger, version of the 3DR radio with big end pins. The instruction sheet included with the new 3DR Radio does not include a pin-out diagram. I took the case apart but the circuit board is not labeled with pin-outs.
Should I presume that the radio pin-out sequence is the same as the previous version? That one went (from top, left to right) [color=#0040FF]DTS TX RX 5V CTS GND[/color].
To clarify my dilemma: what I received with the 3DR radio was one cable with large 4-pin to 5-pin connectors, two cables with micro 6-pin connectors (one with five wires, the other with six wires) and a USB cable with a micro USB end. The cable with the large connectors fits fine on my APM board, but won’t fit the radio. The two cables with micro connectors fit the radios but won’t fit my APM. So I have to splice something together, but there’s no circuit diagrams showing the pinouts on the radio. And I’m worried because the small cables have moved the red wire from the center (as it was positioned on the big-connector cable) to the edge. Since I think this is the 5VDC line, that move leads me to suspect the rest of the connections.
I think I can now answer my own question, thanks to this post by R. D. Starwalt with the APM2.5 5V/Vcc Schematic. I believe the correct port on this diagram is labeled DF 13-5P-1.25 DSA. Its pinout is [color=#4000FF]VCC TX RX NC GND[/color] (VCC is the red wire [5VDC] and the NC pin might be No Connection or DTS or CTS).
You didn’t have a DF13 micro connector 5pin to 6pin cable in your shipment?
the Radio DF13 connector pin out is below. You can remake the DF13 6pin cable and DF13 5 pin cable into two cables that are 5pin to 6pin. You can use a small screen driver to lift the tab for each cable and pull it from the plug. Then insert in the correct location on the other plug. You can swap TX/RX if it doesn’t work. NOTE: always double check that GND and 5V are not swap and location is correct and you will have not problem
1 - 5V
2 - RX
3 - TX
4 - RTS
5 - CTS
6 - GND
Thanks for the pin-out, Bill. Yes, I did get a DF13 micro connector 5pin to 6pin cable, but I need to splice it to the bigger connector for the older APM board. Now that I know the pin definitions, it’s no problem. Thanks again.
no problem, you must have an APM2.0, I thought 2.4 was a typo for 2.5