[SOLVED] CPU speed seems different with SDK or mbed

RE: [SOLVED] CPU speed seems different with SDK or mbed

Roger Clark — Fri, 10 Feb 2017 23:24:22 GMT

No worries.

I'd try -O3 instead of -Os and see if it makes much difference, as it will reduce you code side, as -Os will favour speed over size

RE: [SOLVED] CPU speed seems different with SDK or mbed

Nathan O. — Fri, 10 Feb 2017 23:02:11 GMT

I'm not exactly sure as I've started off from a previous project of mine but it might have been based on the blinky one so that makes sense.

RE: [SOLVED] CPU speed seems different with SDK or mbed

Roger Clark — Fri, 10 Feb 2017 21:50:11 GMT

Which example project are you using ?

I checked all the makefiles in SDK 12.1.0 and only the blinky uses -O0 most the rest use -O3

RE: [SOLVED] CPU speed seems different with SDK or mbed

Nathan O. — Fri, 10 Feb 2017 18:01:40 GMT

I found the solution.

In case anyone gets the same issue trying to do bit-banging on the nrf51 : the problem was simply a lack of compiler optimization. I was compiling with -O0. When moved to -Os, the toggle is now done every 125ms.

From there I am able to drive the LED using the RGB_Show function from https://developer.mbed.org/questions/54210/RedBear-nRF51822-driving-NeoPixels/