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Timing considerations
- From: eibach at gdsys dot de
- To: ecos-discuss at sources dot redhat dot com
- Date: 11 Sep 2003 06:02:46 UT
- Subject: [ECOS] Timing considerations
Hello,
one of the things my eCos application has to do is to serve a serial port. Platform is an Atmel EB40A.
The device connected to the serial port needs answers to its requests within 1 ms to work properly.
My idea was the following:
- use the EB40A hardware driver for the serial port
- poll the driver every 1 ms using the cyg_io_read command (non-blocking)
- polling could be triggered by an alarm
- that would require a clock with a timing faster than 10 ms between ticks (which is the standard)
- so i use CYGNUM_KERNEL_COUNTERS_CLOCK_OVERRIDE_... options to set the ticks to 100 us
- then i can trigger the alarm every 10 ticks
Am I on the right way? Has anybody better ideas?
Could changing the time between ticks cause any problems?
Regards,
Dirk Eibach
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