NT910G
User Manual - Telic AG
Pg 19
The modem is fully operational after 8 seconds. Logging onto a network may take longer than this and
is outside the control of the modem. The modem can be configured to start up at the time power is
applied by permanently tying power connector signals TO_IN (pin 4) and VCC (pin 1) together.
DTR must be cycled from low to high.
The TO_IN signal requires a p
ositive “edge” (a sharp” signal transition from low to high) to
turn the modem on. This transition should be a rising signal from 0V (GND) to VCC, or at least
a large fraction of that voltage range, and must be applied at the same time as VCC or after it.
Very slow transitions (significantly slower than many milliseconds) or very small transitions
(e.g. only few volts instead of 0V to VCC) will not turn on the module (since they are not
considered to be a “positive edge”).
Although this will not be an issue in almost all typical applications of the modem, there are a few cases
in which the modem might not recognize the power up signal. This is no failure of the modem itself,
the same would apply to almost any electronic device that provides a separate “power on” or “reset”
signal.
Possible cases are the following:
▪
Large capacitors in your power supply which will lead to slow leading and falling edges (issue
does not apply with modern stabilized switching regulator power-adaptors) AND TO_IN tied in
parallel to VCC (instead of separate dedicated digital signal)
▪
Slow analogue signals used to assert TO_IN
▪
TO_IN signal not before VCC
If you are in doubt, please
▪
Use the mains power adapter that is provided by your distributor and is known to work
properly with your modem.
▪
Make sure that your signal and system design is according to the above.
▪
Consult our support team that will be more than happy to assist you.
5.2
Configuration of the bit rate on the serial interface
Please note that the module used in the terminal does not support auto baud. The configured data
rate is 115200 baud.
▪
Data bits: 8
▪
Stop bits: 1
▪
Parity: none
5.3
Power cycle the modem
There are two ways to switch off (power down) the modem as described below:
