EES3 Hardware Interface Description
3.5 Charging Control
71
EES3_HD_v01.100b
Page 45 of 118
2009-08-12
Confidential / Released
3.5.7
Operating Modes during Charging
Of course, the battery can be charged regardless of the module's operating mode. When the
GSM module is in Normal mode (SLEEP, IDLE, TALK, GPRS IDLE or GPRS DATA mode), it
remains operational while charging is in progress (provided that sufficient voltage is applied).
The charging process during the Normal mode is referred to as
Charge mode
.
If the charger is connected to the charger input of the external charging circuit and the module’s
VCHARGE line while EES3 is in Power-down mode, EES3 goes into
Charge-only
mode.
While the charger remains connected it is not possible to switch the module off by using the
AT^SMSO command or the automatic shutdown mechanism. Instead the following applies:
•
If the module is in Normal mode and the charger is connected (Charge mode) the
AT^SMSO command causes the module to shut down shortly and then start into the
Charge-only mode.
•
In Charge-only mode the AT^SMSO command is not usable.
•
In Charge-only mode the module neither switches off when the battery or the module
exceeds the critical limits of overtemperature or undertemperature.
In these cases you can only switch the module off by disconnecting the charger.
To proceed from Charge-only mode to another operating mode you have the following options,
provided that the battery voltage is at least above the undervoltage threshold.
•
To switch from Charge-only mode to Normal mode you have two ways:
- Hardware driven: 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.
- AT command driven: Set the command
AT^SCFG=MEopMode/Airplane,off
(please do
so although the current status of Airplane mode is already “off”). The module will enter
the Normal mode, indicated by the “^SYSSTART” URC.
•
To switch from Charge-only mode to Airplane mode set the command
AT^SCFG=MEop-
Mode/Airplane,on
. The mode is indicated by the URC “^SYSSTART AIRPLANE MODE”.
•
If
AT^SCFG=MEopMode/Airplane/OnStart,on
is set, driving the ignition line (IGT) activates
the Airplane mode. The mode is indicated by the URC “^SYSSTART AIRPLANE MODE”.
Table 11:
AT commands available in Charge-only mode
AT command
Use
AT+CALA
Set alarm time, configure Airplane mode.
AT+CCLK
Set date and time of RTC.
AT^SBC
Query status of charger connection.
AT^SBV
Monitor supply voltage.
AT^SCTM
Query temperature range, enable/disable URCs to report critical temperature ranges
AT^SCFG
Enable/disable parameters MEopMode/Airplane or MEopMode/Airplane/OnStart