Campbell Scientific SDM-CAN Datalogger to CANbus Interface - Manual (Page 30)

SDM-CAN Datalogger-to-CANbus Interface
1 Bus-On; the SDM-CAN is involved in bus activities. One
of the error counters is equal to or greater than 96.
2 Bus-Off; the SDM-CAN is not involved in bus activities.
All of the error counters are less than 96.
3 Bus-Off; the SDM-CAN is not involved in bus activities.
One of the error counters is equal to or greater than 96.
See data type 28 above for details of the error counters and how to reset them.
3.3.5.9 Read the signature and version number of the SDM-CAN operating system (type
30):
This will return the OS signature and the OS Version number in separate
locations. If the SDM-CAN detects that the OS signature is bad then zero will
be returned.
3.3.5.10 Send Remote Frame Request (type 31):
A special type of CAN frame, called ‘remote frame request’ is transmitted with
the CAN ID specified.
3.3.5.11 Set SDM-CAN internal software switches (type 32):
This data type instructs the datalogger to change some internal software switch
settings that control the way it works. The new switch settings are read from a
specified input location. The settings are encoded within that location in the
format of a four digit number. For explanation purposes the four digits are
represented as ‘abcd’ where each letter is a digit in the range 0 to 9 which
indicates a different type of switch setting.
Once set the switches remain set until changed by another call of P118 or on
loading a different program. Therefore it is only necessary to call a P118 to set
these switches once, after program compilation, or when a switch needs to be
changed using a call of P118 within an IF..THEN program construct (see the
program examples below).
Switch ‘a’: 0 This digit is currently unused; enter zero
Switch ‘b’: 0 SDM-CAN returns the last value captured from the
network, even if read before (Default)
1 SDM-CAN returns –99999 if a data value is requested by
the datalogger and a new value has not been captured
from the network, since the last request.
2-
9
Currently unused
Switch ‘c’: 0 Disable I/O Interrupts (Default) – see Section 3.4.1,
Interrupts Using the I/O Connection
1 Enable I/O Interrupts, pulsed mode
2 Enable I/O Interrupts, fast mode
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