nrf51822 bootloader for spi

[Sam]

I want use anthor MCU update firmware for nrf51822 via SPI port,is there a demo for this ?

[Roger Clark]

There is existing code for the STM32F103 ( and possibly other STM32 series MCUs) to act as a SWD debugger / programmer.

Take a look at the Blackmagic probe code, on github ( by Blacksphere) you should be able to modify it to suit your needs