# Nordic nRF boards (`microbit`)

The Nordic nRF chips are a family of ARM-based System-on-Chip that are designed to be used for low-power and short-range wireless solutions.

The nRF51 series is the first series for short range wireless applications. It is superseded by the nRF52 series. The following machines are based on this chip :

- `microbit` BBC micro:bit board with nRF51822 SoC

There are other series such as nRF52, nRF53 and nRF91 which are currently not supported by QEMU.

## Supported devices

> - ARM Cortex-M0 (ARMv6-M)

> - Serial ports (UART)

> - Clock controller

> - Timers

> - Random Number Generator (RNG)

> - GPIO controller

> - NVMC

> - SWI

## Missing devices

> - Watchdog

> - Real-Time Clock (RTC) controller

> - TWI (i2c)

> - SPI controller

> - Analog to Digital Converter (ADC)

> - Quadrature decoder

> - Radio

## Boot options

The Micro:bit machine can be started using the `-device` option to load a firmware in ihex format. Example:

    $ qemu-system-arm -M microbit -device loader,file=test.hex