Campbell Hausfeld SM4M - Manual (Page 33)

B-1
Appendix B. Telecommunications
Commands
The SM telecommunications commands can be issued to an SM either via a direct
SC532 connection to the Storage Module or via a remote connection where the
SM is connected to a datalogger.
Establishing communication between the Storage Module and a
computer/terminal is discussed in Section 5. The commands permit data storage
and retrieval, switch setting, status checks and other functions.
The Storage Module is ready for a command when it sends its prompt,
‘ %’. The successful execution of a command is also indicated by the
SM returning a ‘ %’. If just a ‘%’ is returned, the command was in
error. ‘ CTRL - S ’ (XOFF) temporarily halts Storage Module responses to
commands. ‘ CTRL - C ’ aborts the response.
The descriptions of some commands refer to the Storage Module pointers (see
Section 4). The Display Location Pointer (DLP) is used to display Storage
Module data. The Storage Reference Pointer (SRP), indicates the next location
to be written to in the Storage Module. The Dump Pointer is an internal Storage
Module pointer used for keeping track of the current start-of-dump for Storage
Module-to-Storage Module data dumps and for the data retrieval options of the
SMS program.
Storage Module telecommunications commands are similar to datalogger
telecommunications commands and consist of numbers and CAPITAL letters. In
the following list telecommunications commands are on the left and their
descriptions on the right.
A
Status
Returns Version number, Switch settings, number of Programs stored, number
of good Data Memory blocks, number of Errors logged (max. = 255), number
of Available storage locations, number of locations Full, Storage Reference
Pointer, Display Location Pointer, Dump Pointer and Checksum (sum of all
transmitted ASCII characters since last %; wraps around at 8192).
The number of Errors logged is a count of bad characters received from the
logger and/or the number of times the module has reset itself as a result of
some unknown cause. Contact Campbell Scientific for advice if this counter
increments regularly. Unlike previous modules this counter does not increment
if corrupted characters are received in telecommunications mode.
Example: V1 S1400 P0 M64 E0 A2052258 F1 R2 L2 D2 C2226 is the
expected response to the A command after an SM4M has been reset.
NOTE:- in Ring mode, when data storage has gone around the memory more
than once the Number of Locations Full will fluctuate. This is because memory
is erased in 64 Kbyte blocks and filled an output array at a time (Section 4).
Refer to the L command for a discussion of the switch settings.
NOTE