FDS - How can I write binary data to flash while receiving via BLE

RE: FDS - How can I write binary data to flash while receiving via BLE

emdi — Mon, 06 Nov 2017 08:34:57 GMT

fds is more like a library to manage a collection of relatively small pieces of data, i.e. records. I don't believe it might be feasible to use a 25k RAM buffer and write it all at once in fds, in order to do that you'd have to use a virtual page of at least 28k in size and fds would need two of such pages, one for data and one to use as swap.

I would stick to fstorage for this, it has a simple API and is much more suited for your requirements. There is an example in SDK 14.1 under examples/peripheral/flash_fstorage.

Regards, emdi

RE: FDS - How can I write binary data to flash while receiving via BLE

Andrew — Mon, 06 Nov 2017 01:34:27 GMT

On further inspection of the documentation, nodic says the following: "To store larger data, increase the virtual page size or use the Experimental: Flash Storage module instead of FDS."

I think your application falls into this description. You just have to decide how risk adverse you are to using experimental modules.

RE: FDS - How can I write binary data to flash while receiving via BLE

chrizz — Sun, 05 Nov 2017 22:49:24 GMT

This was my first thought too Andrew. But since I'm running a freertos based system with a micropython stack I'm afraid of getting in trouble doing it this way. Nevertheless I need to analyze the memory of the system if its possible theoretically.

RE: FDS - How can I write binary data to flash while receiving via BLE

Andrew — Sun, 05 Nov 2017 17:59:34 GMT

The easiest way and likely fastest/safest way, is to allocate a 25k buffer in RAM and after you have all the data, just let the FDS churn through all of it at once.