RTEMS 4.8.1 On-Line Library

Sample Applications Nanosecond Granularity Application

RTEMS Development Environment Guide

3.8: Nanosecond Granularity Application

This sample application is in the following directory:

${RTEMS_ROOT}/testsuites/samples/nsecs/

This sample application exercises the Clock Driver for this BSP and demonstrates its ability to generate accurate timestamps. This application does this by exercising the time subsystem in three ways:

Obtain Time of Day Twice Back to Back
Obtain System Up Time Twice Back to Back
Use System Up Time to Measure Loops

The following is an example of what the output of this test may appear like:

*** NANOSECOND CLOCK TEST ***
10 iterations of getting TOD
Start: Sat Mar 24 11:15:00 2007:540000
Stop : Sat Mar 24 11:15:00 2007:549000 --> 0:9000
Start: Sat Mar 24 11:15:00 2007:3974000
Stop : Sat Mar 24 11:15:00 2007:3983000 --> 0:9000
Start: Sat Mar 24 11:15:00 2007:7510000
Stop : Sat Mar 24 11:15:00 2007:7519000 --> 0:9000
Start: Sat Mar 24 11:15:00 2007:11054000
Stop : Sat Mar 24 11:15:00 2007:11063000 --> 0:9000
Start: Sat Mar 24 11:15:00 2007:14638000
Stop : Sat Mar 24 11:15:00 2007:14647000 --> 0:9000
Start: Sat Mar 24 11:15:00 2007:18301000
Stop : Sat Mar 24 11:15:00 2007:18310000 --> 0:9000
Start: Sat Mar 24 11:15:00 2007:21901000
Stop : Sat Mar 24 11:15:00 2007:21910000 --> 0:9000
Start: Sat Mar 24 11:15:00 2007:25526000
Stop : Sat Mar 24 11:15:00 2007:25535000 --> 0:9000
Start: Sat Mar 24 11:15:00 2007:29196000
Stop : Sat Mar 24 11:15:00 2007:29206000 --> 0:10000
Start: Sat Mar 24 11:15:00 2007:32826000
Stop : Sat Mar 24 11:15:00 2007:32835000 --> 0:9000

10 iterations of getting Uptime
0:38977000 0:38986000 --> 0:9000
0:40324000 0:40332000 --> 0:8000
0:41636000 0:41645000 --> 0:9000
0:42949000 0:42958000 --> 0:9000
0:44295000 0:44304000 --> 0:9000
0:45608000 0:45617000 --> 0:9000
0:46921000 0:46930000 --> 0:9000
0:48282000 0:48291000 --> 0:9000
0:49595000 0:49603000 --> 0:8000
0:50908000 0:50917000 --> 0:9000

10 iterations of getting Uptime with different loop values
loop of 10000 0:119488000 0:119704000 --> 0:216000
loop of 20000 0:124028000 0:124463000 --> 0:435000
loop of 30000 0:128567000 0:129220000 --> 0:653000
loop of 40000 0:133097000 0:133964000 --> 0:867000
loop of 50000 0:137643000 0:138728000 --> 0:1085000
loop of 60000 0:142265000 0:143572000 --> 0:1307000
loop of 70000 0:146894000 0:148416000 --> 0:1522000
loop of 80000 0:151519000 0:153260000 --> 0:1741000
loop of 90000 0:156145000 0:158099000 --> 0:1954000
loop of 100000 0:160770000 0:162942000 --> 0:2172000
*** END OF NANOSECOND CLOCK TEST ***

RTEMS Development Environment Guide