> For the complete documentation index, see [llms.txt](https://docs.arkelectron.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.arkelectron.com/products/gps/ark-gps/hardware.md). # Hardware Reference ## Specifications | Specification | Value | | ------------- | -------------------------------------------------------------------------------------------------------------- | | GNSS receiver | [u-blox NEO-M9N](https://www.u-blox.com/en/product/neo-m9n-module), meter-level, 4 concurrent GNSS | | Interference | Spoofing and jamming detection, RF interference mitigation | | Magnetometer | [Bosch BMM150](https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bmm150-ds001.pdf) | | Barometer | [Bosch BMP388](https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bmp388-ds001.pdf) | | IMU | [InvenSense ICM-42688-P](https://invensense.tdk.com/products/motion-tracking/6-axis/icm-42688-p/), 6-axis | | MCU | STM32F412CEU6 | | Safety button | Yes | | Buzzer | Yes | | Interfaces | 2× DroneCAN (Pixhawk-standard 4-pin JST-GH), debug (Pixhawk-standard 6-pin JST-SH) | | Power | 5 V, 110 mA average, 117 mA max | | Dimensions | 5 × 5 × 1 cm | | Weight | 16 g | ## Pinout ### CAN (×2) — 4-pin JST-GH | Pin | Signal | Voltage | | --- | ------ | ------- | | 1 | 5V | 5.0 V | | 2 | CAN\_P | 5.0 V | | 3 | CAN\_N | 5.0 V | | 4 | GND | GND | ### Debug — 6-pin JST-SH | Pin | Signal | Voltage | | --- | ---------- | ------- | | 1 | 3.3V | 3.3 V | | 2 | USART2\_TX | 3.3 V | | 3 | USART2\_RX | 3.3 V | | 4 | FMU\_SWDIO | 3.3 V | | 5 | FMU\_SWCLK | 3.3 V | | 6 | GND | GND | ## LEDs The board has a safety LED, a GPS fix LED and an RGB status LED. | Status LED | Meaning | | ----------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Green, fast blink (10 Hz) | Node firmware running. It does not change with CAN traffic. | | Green, slow blink (1 Hz) | Bootloader listening for CAN traffic | | Blue, blinking (2 Hz) | Bootloader waiting for a node ID from the flight controller | | Blue and green, blinking (3 Hz) | Bootloader waiting up to 3 s for the flight controller to start a firmware update | | Red, green and blue together (3 Hz) | Firmware update in progress | | Red, blinking | Firmware update error. 1 Hz: the flight controller returned a file error. 2 Hz: the flight controller stopped responding. 4 Hz: the image failed its CRC check. A failed update restarts the node after 20 s. | | White, fast blink (10 Hz) | GPS passthrough, entered by holding the safety switch at power-up. See [u-blox Firmware Update](/knowledge-base/knowledge-base/ublox-firmware-update.md). | Without valid firmware the node stays in the bootloader until the flight controller flashes it. If the status LED blinks red, check the following: * Make sure the flight controller has an SD card installed. * Make sure the ARK GPS has `ark_can-gps_canbootloader` installed prior to flashing `ark_can-gps_default`. * Remove binaries from the root and ufw directories of the SD card and try to build and flash again. ## 3D Model and Case | File | Contents | | -------------------------------------------------------------------------------------------------------------------------------------- | -------------------- | | [ARK\_GPS\_Rev\_3\_3D\_Model.step](https://github.com/ARK-Electronics/ark-hardware/raw/main/ARK_GPS/model/ARK_GPS_Rev_3_3D_Model.step) | Board, rev 3 | | [Top\_Case\_Rev\_1.stl](https://github.com/ARK-Electronics/ark-hardware/raw/main/ARK_GPS/case/Top_Case_Rev_1.stl) | Case top, rev 1 | | [Bottom\_Case\_Rev\_1.1.stl](https://github.com/ARK-Electronics/ark-hardware/raw/main/ARK_GPS/case/Bottom_Case_Rev_1.1.stl) | Case bottom, rev 1.1 | All files: [ARK\_GPS in ark-hardware](https://github.com/ARK-Electronics/ark-hardware/tree/main/ARK_GPS) ## Schematic and BOM | File | Contents | | ----------------------------------------------------------------------------------------------------------------------------------------- | ------------------------ | | [ARK\_GPS\_Rev\_3\_Schematic.pdf](https://github.com/ARK-Electronics/ark-hardware/raw/main/ARK_GPS/schematic/ARK_GPS_Rev_3_Schematic.pdf) | Schematic, rev 3 | | [ARK\_GPS\_Rev\_3\_BOM.xlsx](https://github.com/ARK-Electronics/ark-hardware/raw/main/ARK_GPS/bom/ARK_GPS_Rev_3_BOM.xlsx) | Bill of materials, rev 3 | --- # Agent Instructions This documentation is published with GitBook. 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