41
In the
CSD Only
mode, in which data transmission is possible only via CSD, GPRS connection, offline
mode, remote firmware updating and settings change and Modbus protocol for COM port are unavailable.
4.15. Watchdog Timers
The modem provides continuous monitoring of the GSM module state. If the GSM module stops responding
to the service commands, it restarts. However, if there has been a fault, but the module continues to respond to
the service commands, the module will not restart. In case of such fault, the modem is fitted with two types of
watchdog timers.
The modem has an interval and daily watchdog timers. The interval watchdog timer restarts the module at
the specified interval after its last activation. Default restart interval
– 24 hours.
The daily watchdog timer restarts the module once a day at the specified time. By default, daily timer is disa-
bled. Watchdog timer is set up in the tab
Settings
Advanced
WDT
of the ATM Control utility.
4.16. Real-Time Clock (RTC)
Real-time clock (RTC) is a source of time for the modem services which require timestamps or compliance
with a schedule to operate. For example, the modem determines time of SMS sending and receiving via RTC
and starts the watchdog timers. RTC configuration is set up in the tab
Settings
Advanced
RTC
of the
ATM Control utility.
When enabled, the modem performs the RTC verification. If there has been the RTC fault, both LEDs glow
for 4 seconds, and the current time is set to 0:00:00.
When the modem is connected to the iRZ Collector server, the modem RTC time is synchronized with it.
4.17. GPIO Pins Operation
To control external devices (for example, sensors), the modem has three configurable GPIO pins (see Fig.
2.7). Pin 1 and 2 can be configured both as "input" and "output"; pin 2 can be configured as ADC. Pin 3 is pow-
er, always operates as an "output".
The modem GPIO is set up in the tab
Settings
Advanced
GPIO
of the ATM Control utility.
4.17.1. Setting Up Pins of an "Input" Type
The pin set to "input" can operate in the normal or inverse modes. In the normal mode the input high level
(level "1") is regarded as an active signal, and the low level (level "0")
– a passive one. In the inverse mode the
modem perceives high input/output signal as an active signal, and low signal
– as a passive one.
