Digicom pocket GSM User Manual page 16

PocketGSM
C) SERIAL CABLE NOT COMPLETED
In case your application (eg. PLC) supports only TD and RD signals (Trasmission and
Reception), it is however possible to connect it to the PocketGSM. In this case you will
use a non-completed serial cable; for this reason it is important to configure PocketGSM
so that it ignores the serial criteria not present. Usually PocketGSM, during the
communication phase, checks the following criteria: 108 (Data Terminal Ready) and 105
(Request To Send): to disable them use the commands AT&D and AT+IFC.
Examples:
Command: AT&D0
Command: AT&D2
Answer: OK
Command: AT+IFC=0,0 (Criterion 105 ignored: flow control OFF)
Command: AT+IFC=2,2 (Criterion 105 managed as per specification: flow control ON)
Answer: OK
D) DATA TRANSFER
PocketGSM can call and be called by analog (PSTN), digital (ISDN) and GSM devices.
Usually DATA connections with analog modems are at 9600bit/s (V.32 protocol); ISDN
connections use V.110 protocol with speed at 9600bit/s. The data transfer with another
GSM device is carried out using V.32 or V.110 protocols.
DATA Calls
Using the ATD command it is possible to make a call. For example, to call the number
0123456789 you must send to the modem the command ATD0123456789<Enter>.
Depending on the AT+CBST command setting it is possible to program PocketGSM for
analog, digital or GSM calls:
AT+CBST=0,0,1 connection with analog or GSM modems in multistandard (V.32)
AT+CBST=7,0,1 connection with analog or GSM modems only in V.32 at 9600bit/s
AT+CBST=71,0,1 connection with digital or GSM modem only in V.110 at 9600bit/s
(Criterion 108 ignored)
(Criterion 108 managed as per specification)
3.4
Functional Examples