Specifications

Chapter 17 – Hardware-Related Commands
Multi-Tech Systems, Inc. AT Commands for EDGE (E1) Modems (S000474A) 280
17.4 AT^SSYNC Configure SYNC Pin
Description: The AT^SSYNC command serves to configure the SYNC pin of the application interface. Please
note that the SYNC pin may be assigned different functions: Depending on the design of the host
application, the pin can either be used to indicate the current consumption in a transmit burst or
to drive a status LED connected to the specified pin.
Syntax: Test Command: AT^SSYNC=?
Response: ^SSYNC:list of supported <mode>s
OK
Read Command: AT^SSYNC?
Response: ^SSYNC:<mode>
OK
Write Command: AT^SSYNC=<mode>
Response: OK
Parameter:
<mode> Operation mode of the SYNC pin. Setting is stored in non-volatile memory.
0 SYNC mode:
Enables the SYNC pin to indicate growing power consumption during a transmit burst.
You can make use of the signal generated by the SYNC pin, if power consumption is your
concern. To do so, ensure that your application is capable of processing the signal. Your
platform design must be such that the incoming signal causes other components to draw
less current. In short, this allows your application to accommodate current drain and thus,
supply sufficient current to the GSM engine if required. Default.
1 LED mode:
Enables the SYNC pin to drive a status LED installed in your application.
The coding of the LED is described in "ME Status Indicated by Status LED Patterns"
below.
2 LED mode:
Like <mode>=1, but additionally, enables different LED signals in SLEEP mode depending
on the status of PIN authentication and network registration. See AT+CFUN for SLEEP
mode details.
ME Status Indicated by Status LED Patterns
The following table lists the possible patterns of status LED behavior and describes the ME operating status
indicated by each pattern if AT^SSYNC parameter <mode>=1 and <mode>=2. To better monitor the operating
states while power saving is enabled, we recommend that priority be given to <mode>=2.
During the transition from one LED pattern to another the "on" and/or "off" periods of the LED may vary in length.
This is because an event that triggers the change may occur any time and, thus, truncate the current LED
pattern at any point.
Modes of the LED and indicated ME functions.
LED Behavior ME operating status if AT^SSYNC=1 ME operating status if AT^SSYNC=2
Permanently off ME is in one of the following modes:
POWER DOWN mode
AIRPLANE mode
NON-CYCLIC SLEEP mode
CYCLIC SLEEP mode with no
temporary wake-up event in progress
1)
ME is in the following mode:
POWER DOWN mode
AIRPLANE mode.
600 ms on / 600ms off Limited Network Service: No SIM card
inserted or no PIN entered, or network
search in progress, or ongoing user
authentication, or network login in
progress.
Same as for AT^SSYNC=1
75 ms on / 3 s off IDLE mode: The mobile is registered to
the GSM network (monitoring control
channels and user interactions). No call
is in progress.
Same as for AT^SSYNC=1
75 ms on / 75 ms off /
75 ms on / 3 s off
One or more GPRS contexts activated. Same as for AT^SSYNC=1
500 ms on / 25 ms off Packet switched data transfer in
progress.
Same as for AT^SSYNC=1
Table continued on next page