nRF51822 flash programming over SWD

[harryB]

Hi, I would like to program nRF51822 flash over SWD interface. I have another micro LPC1100 series that has the flash image for RF51822 and connected to nRF51822 over SWDIO and SWCLK pins. What are the steps to achieve so? Could anyone please share the details or existing implementation? or better approach which doesn't require any tools like Segger or J-Link.

[RK]

That's not very easy. You'd need a complete, well at least a partial, implementation of the SWD protocol on the LPC1100, enough to bit bang the SWD interface on the nrf51 into responding, halting and uploading data.

Then you'd need to write more code on the LPC1100 to drive the SWD code and do the upload, which means understanding the SWD protocol.

CMSIS-DAP has a free source implementation of a bit banger for SWD, it's designed for use with USB but the underlying code could be used.

This is a very hard way to do it. You'd be better off putting a bootloader on the nrf51 and using one of the serial bootloader implementations to talk to it. That means however programming the chip once with some kind of commercial programmer (or buying modules which have bootloaders on them).

[harryB]

Hi RK, Thank you very much for quick reply. I just downloaded the CMSIS-DAP Beta 0.01 from the link text this is the source you are talking about? If you intend to refer different code base please let me know.