lpcware

LPC4337 and LPCXpresso 6.1.0: cycle and cycledelta not working

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by pabloridolfi on Wed Oct 30 18:08:05 MST 2013
Hello everybody,

I need to measure some execution times in my firmware. A simple blinky program, without multicore, only Cortex-M4 running.
I'm currently using a Xplorer board with LPC4337JET100 and a LPC-Link 2 debugger. I have LPCXpresso IDE 6.1.0 installed on Ubuntu 13.10 64-bit and Windows 8 64-bit, and in both cases 'cycle' and 'cycledelta' registers seems not to be working. I also checked memory view for addresses 0xE0001000 (DWT_CTRL) and 0xE0001004 (DWT_CYCCNT) and I don't see normal values. See image below:

[img]https://dl.dropboxusercontent.com/u/12754474/Screenshot%20-%20301013%20-%2021%3A53%3A41.png[/img]

I also used JTAG and SWD modes for the debugging session, the problem is still there. Is it possible that this microcontroller doesn't have an DWT unit? I tried with a LPCXpresso-LPC1769 board and it works just fine. The memory view shows this:

[img]https://dl.dropboxusercontent.com/u/12754474/Screenshot%20-%20301013%20-%2022%3A02%3A39.png[/img]

[edit] I installed Keil uVision 5 and used ULINK-ME, the DWT registers are working. So the problem might be in the LPC-Link 2 debugger.
[img]https://dl.dropboxusercontent.com/u/12754474/keil.png[/img]


Any advice will be appreciated.
Kind regards,
Pablo

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