55xGenComm1_29
31
GenComm Page 2 - Modem Settings
1. Modem control strings can contain any ASCII characters and are padded with spaces (ASCII
0x20), NULL terminators are not used.
2. Each string is automatically suffixed with <CR><LF> so these should not be included in the
string, strings are not automatically prefixed with ‘AT’ so these must be included when required.
3. A string may contain a meta character consisting of 3 tildes (~~~) which indicates that a pause
of 1 second should be introduced before the rest of the string is sent to the modem. This meta
character may be repeated if longer delays are required. The tildes will not be sent to the
modem.
4. If a dialling string contains only spaces (ASCII 0x20) it will not be used in the dialling sequence.
5. The meaning of the modem’s mode is described in the table below.
6. The modem dial back string can be used by a master to call the slave device, it is never used
by the slave device.
7. The SMS enable flag enables the transmission of SMS messages over a GSM modem, the
method of transmission, circumstances that trigger a transmission and contents of the
messages are not defined in this standard.
8. The SMS message centre number and recipient number are in the same format as the other
modem control strings and are only used when the SMS system is activated by the SMS
enable flag, their use is not defined in this standard.
Registers
These are all read/write registers.
Register
offset
Name Min
value
Max
value
Scale
factor
Units Bits/
sign
0 Modem
mode
0
16
1
Connect delay time
1
60
1
Secs
16
2
Number of retries on each
number
0 99 1 16
3
Delay between retries
0
60
1
Secs
16
4
Delay before repeat cycle
0
3600
1
Secs
16
5
Short message service (SMS)
enabled
No Yes 16
6-63 Reserved
64-79
First dialling string
ASCII
ASCII
256
80-95
Second dialling string
ASCII
ASCII
256
96-111
Third dialling string
ASCII
ASCII
256
112-127
Fourth dialling string
ASCII
ASCII
256
128-143
Modem initialisation string - not
auto-answer
ASCII ASCII
256
144-159
Modem initialisation string - auto-
answer
ASCII ASCII
256
160-175
Modem hang-up string
ASCII
ASCII
256
176-191
Modem dial back string
ASCII
ASCII
256
192-207
Short message service (SMS)
message center number
ASCII ASCII
256
208-223
Short message service (SMS)
recipient number
ASCII ASCII
256
224-255
Reserved for more modem
strings
512