Where can I find the pin numbers for the various nRF52 peripherals (I2C, SPI, UART, etc)?
One extremely flexible feature of the Nordic nRF52 on our BMD-300 Series is the ability to map any GPIO pin to any internal function block. That's why you don't see specific pin assignments in the BMD-300 Series Datasheet.
Customer firmware can, however, take full advantage of these features. All development tools available for the nRF52 function the same with our BMD-300. In addition to our documentation, you may want to take a look at the documents and tools that Nordic Semiconductor provides:
Additional Pins to Pay Attention to:
The BMD-300 Series are essentially extensions of the nRF52832 with the high-speed crystal, inductor for the LDO and antenna. All nRF52 specifications from Nordic apply.
A couple notes for pin assignments:
- P0.22 through P0.31: Nordic recommends avoiding high-speed or high-current assignments due to the proximity to the RF sections of the nRF52 (link for details)
- P0.09 and P0.10: The NFC pins can be assigned for any other purpose provided their setup is changed. A permanent shunt exists between these pins to protect the nRF52 from damage when used for NFC. To minimize leakage current, ensure these two pins are at the same level when not in use.
- P0.21: The only pin defined as being able to be set as the reset input. It can, however, be assigned to any other function. It can also be used as a wake source without configuring it for reset. While the WIC is not implemented, Nordic provides the GPIO Tasks & Events (GPIOTE) that can be configured for the wake source.
- See the product specification for "system off mode" (link for details)
- It is possible to switch functions from a GPIOTE wake input to another peripheral function. Be sure to stop the affected peripherals when making the switch.
- P0.02 through P0.05 & P0.28 through P0.31: The only ADC assignable pins.
The BMD-340 uses the nRF52840 which has its own set of pin notes on the Product Specification pin assignment page. Note that mentions of "low frequency" indicate < 10KHz.