Kinetis Design StudioのトピックRe: Need to be able to see cycle counts in KDS

Need to be able to see cycle counts in KDS

ve3id — Tue, 24 Jan 2017 14:45:27 GMT

Hi,

I am teaching a third-year college computer engineering course in micro controllers. I have just migrated from the 9S12 using Codewarrior to KDS 3.2.0 using the FRDM-K64F and SDK 2.1.

Part of the course discusses cycle times for each assembly instruction, and with codewarrior I could demonstrate this in action by using the simulator.

I cannot find any similar tool in KDS. Can anybody point me to a way to do this?

cheers,

Nigel Johnson

Re: Need to be able to see cycle counts in KDS

BlackNight — Wed, 25 Jan 2017 13:52:17 GMT

Hi Nigel,

there is the QEMU simulator which supports the ARM Cortex, see The GNU ARM Eclipse QEMU. I have not really used it (yet), that was definitely I was looking for using in my own course.

As an additional pointer: the M3/M4 core has a hardware cycle count register you could use (see ARM Information Center as reference). It is used eg. it in the Segger SystemView (see ) as time base to measure the time between API calls and events (see Segger SystemView: Realtime Analysis and Visualization for FreeRTOS | MCU on Eclipse ). If you are using it in software, make sure you have turned on the debug block on the device.

I hope this helps,

Erich

Re: Need to be able to see cycle counts in KDS

ve3id — Sun, 29 Jan 2017 19:11:56 GMT

Eric, I have Embedded Systems register View installed, I am not sure if I followed your instructions or if it is now standard (I am getting punch drunk after working on this for so long :-) but I cannot see the DWT_CYCCNT register. I have expanded all the groups in EmbSys Reg view and nothing. Any ideas? I am getting desparate since i have to have a lab converted to the K64F by Tuesday and I had no idea it was going to be so difficult to find cycle counts!

I also downloaded the simulator but it only works for ST micro implementations!

cheer,

Nigel

Re: Need to be able to see cycle counts in KDS

BlackNight — Mon, 30 Jan 2017 08:30:28 GMT

Hi Nigel,

the CMSIS-SVT files delivered with the EmbSysReg do not include most of the ARM core registers, mostly the vendor specific ones.

I have an article posted (link below) how you could do cycle counting and inspect the value in the debugger:

Cycle Counting on ARM Cortex-M with DWT | MCU on Eclipse

I hope this helps,

Erich