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Here+ RTK Rover/Base Kit

This is a GNSS base/rover receiver set that was intended to be paired with UAVs using the Pixhawk flight controller. It is based on the NEO-M8P-0/2 which is capable of dual-constellation single band RTK. The base station is a GNSS only, and required a separate telemetry radio. The rover includes the GNSS as well as I2C modules for IMU, mag, and barometric pressure.

Base

U-Blox NEO-M8P-2 with a USB port and exposed pins for UART1 Rx/Tx/GND. SMA for antenna. The -2 variant of the M8P can be used as an RTK base or rover, sending or receiving RTCM corrections.

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Rover

The rover hardware includes a GNSS + antenna and six I2C devices. It has an eight pin JST-GH connector which is externally accessible by way of a cable passthrough in the case which carries the UART and I2C to the flight controller. It also has a four pin connector (also JST-GH) for USB, though only data is carried on this connector, power must be applied via the larger connector.

The Here+ v1 rover differs significantly from the 2/3/4 in that the sensors are connected to the I2C bus directly, and the module does not support the CAN protocol. In the 2/3/4, the sensors are connected to an STM32 which can either emulate I2C devices, or provide the data on a CAN bus. For the purposes of tinkering/hacking, having the hardware exposed directly via their own I2C interfaces has some advantages.

GNSS

The rover's GNSS is a U-Blox NEO-M8P-0. It is accessible via UART1 on the eight pin connector, and USB on the four pin connector (it uses the same as the base unit.) Note: the USB connector does not supply power to the rover or the GNSS module, voltage must be separately applied to pin 1 of the eight pin connector.

The GNSS antenna is a Taoglas CGGBP.25.4.A.02 1“ ceramic patch.

I2C devices

Device Type Part Address Misc
Magnetometer AK09916 0x0C
Magnetometer LIS3MDL 0x1C
Magnetometer HMC5883L 0x1E
LED Driver Toshiba TCA62764 0x55
IMU MPU-9250 0x71
Barometer MS5611 0x77
here_rtk_kit.1764083228.txt.gz · Last modified: by millerjs

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