Cinterion
®
ELS31-VA/ELS51-VA Hardware Interface Description
2.1 Application Interface
56
ELS31-VA_ELS51-VA_HID_v01.000
2017-01-04
Confidential / Preliminary
Page 45 of 106
2.1.16.4
Fast Shutdown
The GPIO4 interface line can be configured as fast shutdown signal line FST_SHDN. The con-
figured FST_SHDN line is an active low control signal. Before setting the FST_SHDN line to
low, the ON signal should be set to low (see
).
By default, the fast shutdown feature is disabled. It has to be enabled using the AT command
AT^SCFG "MEShutdown/Fso". For details see
.
If enabled, a low impulse of 10 milliseconds on the FST_SHDN line starts the fast shutdown
procedure.The fast shutdown procedure still finishes any data activities on the module‘s flash
file system, thus ensuring data integrity, but the module will no longer deregister gracefully from
the network. On-going flash access cycles (writing/deleting) will be finalized within less than
200 milliseconds. If the module is in power sleep mode, the 200 milliseconds maximum shut-
down time will start after the module wakes up from sleep mode.
Figure 21:
Fast shutdown timing
Please note that if enabled, the normal software controlled shutdown using AT^SMSO will also
be a fast shutdown, i.e., without network deregistration. However, in this case no URCs includ-
ing shutdown URCs will be provided by the AT^SMSO command.
BATT+
ON
VCORE
V180
Fast shut down procedure
Power down
EMERG_RST
FST_SHDN
max. 200ms
min. 10ms