Campbell Scientific SDM-CAN Datalogger to CANbus Interface - Manual (Page 50)

SDM-CAN Datalogger-to-CANbus Interface
The CANBUS is scanned for the following baud rates:
20K, 50K, 125K, 250K, 500K, 800K and 1 Megabaud.
As soon as the baud rate is found, the bus parameters TQUANTA, TESG1,
TSEG2 and frames / n*50msec are reported to the user. The SDM-CAN will
then be set to, and stay at, this baud rate until the changed by the datalogger
following a re-compilation of the program by the user, or by a datalogger SDM
communications error which will force the SDM-CAN to be reset. If no baud
rate can be detected, an error is reported to the user.
Because any communication errors cause a default back to the datalogger set
baud rate, it is not recommended that this command is used for anything other
than CANBUS diagnostic purposes.
CLRERROR – Takes no parameters. This command will clear all the error
counters Transmit, Receive, Overrun and Watch-dog to zero and clear a bus off
condition.
COMP – Takes no parameters. This command will force the datalogger to re-
send all of the configuration information again. This command is used by
Campbell Scientific for debugging purposes only.
HELP or ? – Prints a list of valid user commands.
HEXDUMP aaaa bbbb – The first parameter ‘aaaa’ is the start address and
the second parameter ‘bbbb’ is the number of bytes to dump. This command
will dump the SDM-CAN’s full memory address range in a hex format. Each
line that is output starts with the address followed by a16 byte value and then
the ASCII characters. Any unprintable characters are represented by a ‘.’
character.
MONITOR nnnn – This command takes parameters in the range n=0 to n=2,
where:
0 = monitor CANBUS for IDs used by the datalogger program (this is the
default if the parameter is missing).
1 = monitor CANBUS for IDs that are allowed to pass through the simple
IDfilter.
2 = monitor all CANBUS messages on the bus.
The monitor command will output a CAN frame in hex format when received.
This command has a ring buffer that can hold 20 frames before it overflows.
Monitor mode will not miss frames when they come in high speed burst’s. This
command will perform better the higher the terminal baud rate.
The hex output format of the command is as follows:- Info byte, Frame ID,
Frame Data. To exit this command use ‘CTRL-C’.
SETCANBAUD nnnn nnnn nnnn – Sets the CANBUS baud rate. The
parameters are in the following order: TQUANTA = 0 - 63, TSEG1 = 0 - 15
and TSEG2 = 0 to 7. See Section 3, Programming CR10X, CR7 and CR23X
Dataloggers to use the SDM-CAN, which gives details on how to calculate
baud rate using these parameters. The SDM-CAN baud rate will stay set until it
is changed by the datalogger following a program re-compilation by the user,
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