Recently I’ve been looking into creating a custom STM32 board and then using it with PlatformIO - Zephyr. However, I now have a several small minimal nRF51802 boards that I’m hoping to use as custom boards.
I’m trying to re-purpose a nRF51802 board that is no longer required. It was a board housed in a small plastic enclosure, attached to a 3M filtrete smart air filter. After changing the filter, I thought I’d open up the BT board and analyze it.
As shown below, the board (3cm x 3.5cm) is quite minimal design, running off a CR2032 battery, has the standard J-Link connector pads, and exposes two GPIOs. These are accessible from a small cutout on the board enclosure. I suspect the exposed GPIOs were probably used for a UART or I2C, or as standard GPIOs for some other diagnostic function.
The board’s BT exposes several services, including a battery service, which is used to detect the battery life. The board sends BLE notifications to a 3M app as when to change filter, in addition, any other processing the board does to detect air quality or amount passing throw the filter.
According to the Nordic specs, the nRF51802 is an ultra-low power SoC, 32-bit ARM Cortex-MO with 256KB flash, 16KB RAM and BLE. It a low cost variant of the nRF51822 (used in BBC micro:bit, beacons & other BLE boards) with the same functionality but with 2dB less RX sensitivity.
What are my options to derive a custom board definition and reuse?
I can probably use the Nordic SDK but would prefer to use PlatformIO with either an Arduino core or Zephyr (though unlikely as nRF51802 isn’t a Zephyr supported SoC).
I didn’t see any Arduino core for the nRF51802 but was wondering if a nRF51822 Arduino core definition could re-used.
Can anyone with nRF51 experience or custom board development please chime in?
Other than using the Nordic SDK, Do you think that the nRF51802 board can be used with PlatformIO Arduino or Zephyr?
I have several these nRF51802 boards. So, if anyone (maxgerhardt?) is interested, I would be glad to share more info and forward one of the boards if anyone is up for a challenge! The reward would be a low board running, with ability to develop using PlatformIO with J-Link debugging.