nRF52832 Flash programming time via SWD

[masamasa]

Hi

I'm using nRF52832 and trying to make programming patterns via SWD myself, and want to make programming time short.

I have a question about flash programmng time via SWD.

How long does it take to write 512kB flash area via SWD ?

Now I see "nRF52832 Production Programming (nWP-027).

In chap 6, it takes around 10seconds to write entire flash.

But it seems more.

Writing data via SWD, I think  it needs at least 6 commands.(TAR/DRW/RDBUFF × 2( Write Flash and READ READY reg).

If SWD running at 3MHz, 6 commands takes 92ns to send only commands.

To write 512kB, it needs over 12s without CPU wait,  resend command etc.

It seems effective time will be more, quite longer than 10 s.

I have misunderstanding ? 

Best Regards.

[Amanda Hsieh]

Hi, 

 To write the entire flash of an nRF52832 device is approximately 8.85 seconds: (512 * 1024) / 4 * (67.5 * 10^-6). Please see the detail in the nWP027 - nRF52832 Production Programming- Programming section. 

-Amanda H.

[masamasa]

Thank you for your answer.

What is the maximum SWDCLK speed of the nRF53832 ?

It seems it is impossible to write one word for 67.5us with 3MHz SWDCLK  freq, cos write flash and read READY reg are needed. 

Is it possible higher than 3MHz ? Or is it possible to write flash absolutely without reading READY reg ?

[Turbo J]

You can write into RAM, then additionally write and use a small function in RAM as a copy-to-flash function. OpenOCD  flashing works like this IIRC.

[Nguyen Hoan Hoang]

yeah, it takes about 30s.

[Amanda Hsieh]

Hi, 

masamasa said:

What is the maximum SWDCLK speed of the nRF53832 ?

Max SWDCLK is 8MHz. 

-Amanda H.