Campbell COM110A, Руководство пользователя

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E-1
Appendix E. Resetting the COM110A
Module under Program Control
This Appendix describes how the datalogger can be used to send commands to the COM110A
to reset the module and also enable the lowest power mode which still allows incoming calls.
E.1 Principle of Control
To reset the COM110A and change its mode of operation it can be sent commands
by the datalogger by embedding commands within a datalogger program. The
commands are identical to those that could be typed into a terminal emulator.
To reset the modem the command AT+CFUN=1<CR> is sent. This attempts to
disconnect the modem from the network, fully resets the GSM module to a power
up state and then reconnects it to the network. This entire process can take up to
30 seconds, although the module will accept non-network related commands
within a few seconds of receiving the reset command.
In addition the example below turns off the automatic resetting mode, which
negates a setting used, in the past by CS, with some older modules that reset the
modem every 24 hours. (That mode is not now recommended by many networks
as it does not cleanly log off the network.) Clearly if the logger is controlling the
reset process the automatic process is redundant.
E.2 CRBasic Program Example
This example can be used on the CR800 series, CR1000 and CR3000 dataloggers.
It uses the standard CRBasic serialopen, serialout and serialclose commands to
send out configuration commands to the modem. The example shows using a slow
sequence to reset the modem every 12 hours, using the command AT+CFUN=1.
'CR1000 Series Datalogger
'Example program showing how to regularly reset the GSM modem
'The modem control is done in a slow sequence to avoid interference with measurements
'Declare Public Variables
'Example:
Public PTemp, batt_volt
'Main Program
BeginProg
'Normal measurements in the main scan here
Scan (1,Sec,0,0)
PanelTemp (PTemp,250)
Battery (Batt_volt)
'......etc
NextScan
'-------------------------------------------------------------------
'Modem control slow sequence - can be cut and pasted as self-contained
'Set this constant to match the port the modem is connected to
Const Modemport=COMRS232
Const Modembaud = 115200 'Change to match modem baud rate