NRF51822 ± Arduino Uno / ATmegaXXX?
You can use the NRF51822 as module with AT firmware attached to Arduino. Then you need only the AT commands reference and some examples how to send AT commands and parse the response.

Or you can use the 32-bit ARM cortex-m0 micro-controller inside NRF51822 with Arduino nrf5 package. It requires a programmer/debugger hardware for sketch upload.