Campbell CR850, Operator'S Manual

Page: 489 / 566

Appendix A. CRBasic Programming Instructions
489
•
Com310
•
ComSDC7
•
ComSDC8
•
ComSDC10
•
ComSDC11
•
Com1 (C1,C2)
•
Com2 (C3,C4)
•
•
•
Com32 – Com46 (available when using a single-channel expansion
peripheral. See the appendix Serial Input Expansion Modules )
Baud rate on asynchronous ports (ComRS-232, ComME, Com1, Com2, and
Com32 - Com46) default to 9600 unless set otherwise in the
SerialOpen()
instruction, or if the port is opened by an incoming PakBus
®
packet at some other
baud rate. Table Asynchronous Port Baud Rates
(p. 492)
lists available baud rates.
In general, PakBus
®
instructions write a result code to a variable indicating
success or failure. Success sets the result code to 0. Otherwise, the result code
increments. If communication succeeds, but an error is detected, a negative result
code is set. See
CRBasic Editor Help for an explanation of error codes. For
instructions returning a result code, retries can be coded with CRBasic logic as
shown in the
GetVariables() example in CRBasic example Retries in PakBus
Communications
(p. 492).
The
Timeout
argument is entered in units of hundredths (0.01) of seconds. If 0 is
used, then the default timeout, defined by the time of the best route, is used. Use
PakBusGraph Hop Metrics to calculate this time (see datalogger support software
(p. 76)
). Because these communication instructions wait for a response or timeout
before the program moves on to the next instruction, they can be used in a
SlowSequence scan. A slow sequence will not interfere with the execution of
other program code. Optionally, the ComPort parameter can be entered preceded
by a dash, such as
-ComME
, which will cause the instruction not to wait for a
response or timeout. This will make the instruction execute faster; however, any
data that it retrieves, and the result code, will be posted only after the
communication is complete.
AcceptDataRecords
Sets up a CR800 to accept and store records from a remote PakBus datalogger.
Syntax
AcceptDataRecords(PakBusAddr, TableNo, DestTableName)
Broadcast
Sends a broadcast message to a PakBus network.
Syntax
Broadcast(ComPort, Message)