Cinterion MC55i, Hardware Interface Description

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MC55i Terminal Hardware Interface Description
3.5 Power Supply
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MC55i_Terminal_HD_v01.201a Page 23 of 47 2010-04-16
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3.5.1 Turn MC55i Terminal on
The IGT_IN signal (pin 4) switches the MC55i Terminal on. After start-up, the MC55i Terminal
enters the net searching state. The IGT_IN signal is activated when an appropriate power sup-
ply unit is plugged to the 6-pole Western jack.
While the PD_IN pin (pin3) is not active (voltage <2V) you can start the MC55i Terminal by ac-
tivating the RS-232 DTR line.
After startup of the MC55i Terminal the RS232 lines are in an undefined state for approx.
900ms. This may cause undefined characters to be transmitted over the RS232 lines during
this period.
3.5.2 Reset MC55i Terminal
An easy way to reset the MC55i Terminal is entering the command AT+CFUN=x,1. For details
on AT+CFUN please see
[1] .
As an alternative, you can shut down the MC55i Terminal as described in Section 3.5.3 and
then restart it as described in Section 3.5.1 .
3.5.3 Turn MC55i Terminal off
Normal shutdown:
•
To turn off the MC55i Terminal use the AT^SMSO command, rather than disconnecting the
mains adapter.
This procedure lets the MC55i Terminal log off from the network and allows the software to
enter a secure state and save data before disconnecting the power supply. After AT^SMSO
has been entered the MC55i Terminal returns the following result codes:
^SMSO: MS OFF
OK
^SHUTDOWN
The "^SHUTDOWN" result code indicates that the MC55i Terminal turns off in less than
1 second. After the shutdown procedure is complete the MC55i Terminal enters the
POWER DOWN mode. The green status LED stops flashing (see
Section 3.9 for a detailed
LED description). The RTC is still fed from the voltage regulator in the power supply ASIC.
Emergency shutdown:
•
In the event of software hang-ups etc. the MC55i Terminal can be switched off by applying
a voltage >5V to the PD_IN pin (pin 3) for more than 100ms.
The PD_IN signal switches the MC55i Terminal off. All internal supply voltages are off,
except for the power down voltage, which still feeds the real-time clock (RTC).
Caution: Use the PD_IN pin only when, due to serious problems, the software is not
responding for more than 5 seconds. Pulling the /PD pin causes the loss of all information
stored in the volatile memory since power is cut off immediately. Therefore, this procedure
is intended only for use in case of emergency, e.g. if MC55i Terminal fails to shut down
properly.