Westermo GS-01 - Manual (Page 28)

28 6195-2201
V24-V25 commands
+IPR – Fixed DTE rate
This commands specifies the data rate at which the DCE will accept commands.
Application to GSM AT+IPR?
GSM to application +IPR: 9 600 current rate is 9 600 bit/s
OK
Application to GSM AT+IPR=?
GSM to application +IPR:(0, 2 400, 4 800, 9 600, 19 200) , possible values (1)
(300, 600, 1 200, 38 400, 57 600, 115 200)
OK
Application to GSM AT+IPR=38 400
GSM to application OK disable autobauding and set rate to
38 400 bit/s
Application to GSM AT+IPR=0
GSM to application OK enable autobauding
Note (1): first set of values indicates the range of auto detectable speeds. The second set
of values indicates all the possible speeds which can be used by DCE.
An autobauding is provided which operates from 2 400 to 19 200 baud.
However some constraints have to be dealt with:
Any AT command issued by DTE must start with a capital ‘A’ and ‘T’ (or ‘\’). If not, DCE
may send back some garbagge characters and get de-synchronized. Should it happen,
DTE shall just issue once or twice ‘AT\r’ (at 2 400 or 4 800 baud) or just ‘AT’
(at 9 600 baud) to get the modem re-synchronized.
The DTE shall wait for 1ms after receipt of the last character of the AT response
(which is always ‘\n’ or 0x0A) to send a new AT command at either the same rate or a
new rate. Shoud this delay ignored, DCE can get de-synchronised. Once again, sending
once or twice ‘AT\r’ or just ‘AT’ causes the DCE to recover.
Be careful: at start-up if autobauding is enabled and no AT command has been received
yet, the module sends all unsolicited responses (like RING) at 9 600 baud.