Pinout and schematic for the Telemetry 2 port, which can also be configured as IRDA or extra I2C bus.
On older versions of the RDDRONE-FMUK66, this port could only be used as IRDA. Since RDDRONE-FMUK66 Rev. C, it is by default configured as a free UART, which can be used as Telemetry 2 in PX4. It can still be reconfigured to use it as IRDA or as an extra I2C bus, though pull-up resistors will have to be placed by hand.
Rev. B (and older boards) are not supported anymore. This information is left for reference.
Pin
Signal
Voltage
1
GND
GND
2
UART RX
+3.3V
3
VCC
+3.3V
4
IR-
+5.0V
5
IR+
+5.0V
Pin
Signal
Voltage
1
VCC
+5.0V
2
UART TX
+3.3V
3
UART RX
+3.3V
4
GND
GND