Multi-Tech Systems GPRS (MTMMC-G) Benutzerhandbuch

Chapter 13 – Specific AT Commands  

Multi-Tech Systems, Inc. Wireless GSM/GPRS AT Commands (Document Number S000293I) 

122 

 

Description: 

This command displays the received signal strength indication (<rssi>) for a specified frequency (in 
absolute format). This command is not allowed during communication. 

Values:  

<

absolute frequency>   frequency in absolute format <rssi>   

0 

  -113 dBm or less 

1  

-111 

dBm 

2...30  -109 to -53 dBm 
31 

-51dBm or greater 

99 

not known or not detectable 

AT+WSCAN=<absolute frequency> 

+WSCAN: <rssi> 

AT+WSCAN=50 
 
Note: Request <rssi> of absolute frequency 50 

+WSCAN: 23 
OK 
Note: <rssi> is 23. 

AT+WSCAN=1025 
Note: Request power of absolute frequency 1025 

CME ERROR: 3 
Note: 1025 is not a valid absolute frequency 

Description: 

This command sets or returns the state of the Ring Indicator Mode.  

• 

In up-down RI mode, no pulses are sent before unsolicited AT response, and up-down signals 
are sent when receiving an incoming call. 

• 

In pulse RI mode, an electrical pulse is sent on the Ring Indicator signal just before sending any 
unsolicited AT response in order not to lose AT responses when client tasks are in sleep state. 
Still in RI mode, when receiving incoming calls, electrical pulses are sent on the RI signal.  

• 

Pulse RI Mode + Pulse On Packet Downloaded: based on Pulse RI mode but an electrical pulse 

is also sent on the Ring Indicator signal just before sending a downloaded data packet (GPRS or 
CSD) if the remote client has dropped down his RTS signal. 

0  Up-down RI mode 
1  Pulse RI mode 

2  Pulse RI mode + Pulse on Downloaded Packet 

<n>   used only in mode RI Pulse + Pulse on Downloaded Packet (<mode>=2). 

0  Duration of pulse is 5 

μs 

1-31  Duration of pulse is n x 30 

μs 

Important: Pulse duration may be increased by up to 3 ms, due to interrupt processes 
overhead. 

Note: Remind that this mode corresponds to the case where the remote equipment has dropped its 
RTS signal to stop its flow control. 

syntax: AT+WRIM=<n> 

AT+WRIM=0 
Note: Select up-down RI mode 

OK 
Note: up-down RI mode selected 

AT+WRIM=1 
Note: Select pulse RI mode 

OK 
Note: pulse RI mode selected 

AT+WRIM=2,0 
Note: Select mode pulse RI on downloaded packet, 
pluse duration is 5 

μs 

OK 
Note: mode pulse RI + Pulse on 
downloaded packet selected 

AT+WRIM=? 
Note: Ask the list of possible  values 

+WRIM: (0-2),(0-33) 
OK 
Note:  possible values 0, 1 or 2 

AT+WRIM? 
Note: Ask the current value 

+WRIM: 1 
OK 
Note: current RI mode is pulse RI