EES3 Hardware Interface Description
3.3 Power Up / Power Down Scenarios
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EES3_HD_v01.100b
Page 36 of 118
2009-08-12
Confidential / Released
3.3.3.2
Turn on/off EES3 Applications with Integrated USB
In a Windows environment, the USB COM port emulation causes the USB port of EES3 to ap-
pear as a virtual COM port (VCOM port). The VCOM port emulation is only present when Win-
dows can communicate with the module, and is lost when the module shuts down. Therefore,
the host application or Terminal program must be disconnected from the USB VCOM port each
time the module is restarted.
Restart after shutdown with AT^SMSO:
After entering the power-down command AT^SMSO on one of the interfaces (ASC0, ASC1,
USB) the host application or Terminal program used on the USB VCOM port must be closed
before the module is restarted by activating the IGT line.
Software reset with AT+CFUN=x,1:
Likewise, when using the reset command AT+CFUN=x,1 on one of the interfaces (ASC0,
ASC1, USB) ensure that the host application or Terminal program on the USB VCOM port be
closed down before the module restarts.
Note that if AT+CFUN=x,1 is entered on the USB interface the application or Terminal program
on the USB VCOM port must be closed immediately after the response OK is returned.
3.3.4
Automatic Shutdown
Automatic shutdown takes effect if:
•
the EES3 board is exceeding the critical limits of overtemperature or undertemperature
•
the battery is exceeding the critical limits of overtemperature or undertemperature
•
undervoltage or overvoltage is detected
See Charge-only mode described in
for exceptions.
The automatic shutdown procedure is equivalent to the Power-down initiated with the AT^SM-
SO command, i.e. EES3 logs off from the network and the software enters a secure state avoid-
ing loss of data.
Alert messages transmitted before the device switches off are implemented as Unsolicited Re-
sult Codes (URCs). The presentation of these URCs can be enabled or disabled with the two
AT commands AT^SBC and AT^SCTM. The URC presentation mode varies with the condition,
please see
for details. For further instructions on AT com-
mands refer to
.