topic Getting a time marker LPC55 in LPC Microcontrollers

Getting a time marker LPC55

randylee — Fri, 29 Jul 2022 20:27:15 GMT

I'm doing a bare metal project on an LPC5512 using MCUexpresso and SDK 2.11 using only internal OSC (no external Xtals), 96MHz.

Since I'm doing a loop to check on everything my self (as opposed to FreeRTOS sort of thing), I would like to know what time it is at any given point to a mS (or so) resolution.

Is there a way to just grab a time off the part somehow? Maybe have to run a timer or something or is there like a systick counter or cycle counter somewhere I can grab.

I'm just interested in relative time so nothing fancy like an RTC.

Re: Getting a time marker LPC55

Alice_Yang — Mon, 01 Aug 2022 09:45:19 GMT

Hello,

There is RTC demo , you can refer to:

The RTC project is a simple demonstration program of the SDK RTC driver. It sets up the RTC
hardware block to trigger an alarm after a user specified time period. The test will set the current
date and time to a predefined value. The alarm will be set with reference to this predefined date
and time.

Download from https://mcuxpresso.nxp.com/en/select

Alice

Re: Getting a time marker LPC55

randylee — Tue, 02 Aug 2022 12:53:20 GMT

RTC runs to the second.. I need mS resolution. Or even uS would work as long as I have a 32bit value to play with...

Re: Getting a time marker LPC55

Alice_Yang — Wed, 03 Aug 2022 08:01:17 GMT

Hello,

It can generate 1ms resolution:

Alice

Re: Getting a time marker LPC55

randylee — Wed, 03 Aug 2022 19:33:54 GMT

Figured it out... what I wanted was OSTIMER which will get me what I need with a shade over 30uS resolution.

Hard to see how to use any of this stuff tho... I hate Doxygen generated documentation; it's really not very useful at all.