18
Table 2.3
Terminal strip connector pin assignments
Pin (see Fig.
2.7)
Name
Function
1
GPIO3 (GPO)
Power general-purpose output
2
GPIO2/ADC
Configurable general-purpose output
3
GPIO1
Configurable general-purpose output
4
GND
Ground Connected to the negative terminal of the power supply
2.11. The Modem Status Indication
To display the modem operation status, it is equipped with LED indication. The LEDs are placed above the
SIM card trays.
When you turn on the modem, both LEDs light up for 300 ms. In case of the RTC-timer failure, LEDs can
light up for 10 seconds while RTC is being initialized.
At the modem operation the indication is performed via the LED placed above the tray with an active SIM
card (a SIM card operating at a given moment is called active, the second one
– inactive). LED signal interpre-
tation is shown in 2.4.
Table 2.4
LED indication signals
Active SIM card indi-
cator
Inactive SIM card in-
dicator
Operating mode
300 ms on / 300 ms off
Off
Module loading, SIM card verification, logging to network
150 mc on/
1500 mc off
Off
Establishing GPRS connection
Solid on
Off
GPRS connection is established, the modem is connect-
ed
Off
Off
No power
Single simultaneous blinking (150 ms on / 150 ms off)
Switching off and restart / switching on
Both LEDs are solid
Service Mode
Both LEDs are blinking (150 ms on / 150 ms off)
SIM cards operation error (PIN code error or no SIM
cards in the trays)
