Cinterion EES3, Описание аппаратного интерфейса

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EES3 Hardware Interface Description
3.3 Power Up / Power Down Scenarios
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EES3_HD_v01.100b Page 31 of 118 2009-08-12
Confidential / Released
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During the Charge-only mode EES3 is neither logged on to the GSM network nor are the serial
interfaces fully accessible. To switch from Charge-only mode to Normal mode the ignition line
(IGT) must be pulled low for at least 2 seconds. When released, the IGT line goes high and
causes the module to enter the Normal mode. See also
Section 3.5.7 .
3.3.1.4 Reset EES3 via AT+CFUN Command
To reset and restart the EES3 module use the command AT+CFUN. You can enter
AT+CFUN=,1 or AT+CFUN=x,1, where x may be in the range from 0 to 9. See
[1] for details.
If configured to a fix baud rate (AT+IPR

0), the module will send the URC "^SYSSTART" or
"^SYSSTART AIRPLANE MODE" to notify that it is ready to operate. If autobauding is enabled
(AT+IPR=0) there will be no notification. To register to the network SIM PIN authentication is
necessary after restart.
3.3.1.5 Reset or Turn off EES3 in Case of Emergency
Caution: Use the EMERG_OFF line only when, due to serious problems, the software is not
responding for more than 5 seconds. Pulling the EMERG_OFF line causes the loss of all infor-
mation stored in the volatile memory. Therefore, this procedure is intended only for use in case
of emergency, e.g. if
EES3
does not respond, if reset or shutdown via AT command fails.
The EMERG_OFF signal is available on the application interface. To control the EMERG_OFF
line it is recommended to use an open drain / collector driver.
The EMERG_OFF line can be used to switch off or to reset the module. In any case the
EMERG_OFF line must be pulled to ground for >10ms. Then, after releasing the EMERG_OFF
line the module restarts if IGT is held low for at least 400ms. Otherwise, if IGT is not low the
module switches off. In this case, it can be restarted any time as described in
Section 3.3.1.1 .
After hardware driven restart, notification via “^SYSSTART” or “^SYSSTART AIRPLANE” URC
is the same as in case of restart by IGT or AT command. To register to the network SIM PIN
authentication is necessary after restart.
3.3.1.6 Using EMERG_OFF Signal to Reset Application(s) or
External Device(s)
When the module starts up, while IGT is held low for 400ms, the EMERG_OFF signal goes low
for approximately 220ms as shown in
Figure 5 and Figure 6 . During this period, EMERG_OFF
becomes an output which can be used to reset application(s) or external device(s) connected
to the module.
After this period, i.e. during operation of the module, the EMERG_OFF is an input.
Specifications of the input and output mode of EMERG_OFF can be found in Table 28 .