Hello can any body help me with an idea ,for detection of baud in devicenet thru software which runs in the slave module Regards PMM
- posted
19 years ago
baud detection thru S/W in devicenet CAN
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- posted
19 years ago
I doubt that's possible at all, ultimately.
CAN is quite universally handled by dedicated hardware controllers, so if you want autodetection of baud rates to work well, it should be handled (or at least supported) by your CAN controller, too.
If your particular hardware doesn't support auto-bauding at all, you'll have no symptoms left for software auto-detection to work wih besides the single-bit result of "go, or no go?"
This leaves only brute-force trial and error: watch your CAN controller: if it quickly runs into bus-off state for exceeding its error counts, odds are that's happening because the currently selected baudrate is wrong. Choose a different one. Repeat until you successfully receive messages.
-- Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de) Even if all the snow were burnt, ashes would remain.
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- posted
19 years ago
That's how it's done. Put the CAN controller into listen-only mode. Then cycle through the three baud rates until you receive valid messages.
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at and DIAGRAMS...
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- posted
19 years ago
Mr Koppe talked about technical solutions at the 9th International CAN Conference.
Regards Heinz
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- posted
19 years ago
There is a Philips Application Note (AN97076) that describes (among other things) a method of automatic bit-rate detection with the SJA1000 CAN controller. See section 5.6.
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-- Kevin