User's Manual

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H380-GL Hardware User Manual Page
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3.5.2.2 N.O. SIM card slot
The reference circuit design for the N.O. (Normally Open) SIM card slot is shown in Figure 3-13:
Figure 3-13 Reference Circuit for N.O. SIM Card Slot
The principle description for N.O. SIM card slot is shown in the following:
 When the SIM card is detached, the CD and SW pins will open, and the SIM_DETECT is low.

When the SIM card is inserted, the CD and SW pins will short, and the SIM_DETECT is high.
3.5.3 USIM Hot-Plugging
H380 supports SIM card hot-plugging function; it judges whether SIM card is inserted or removed by
detecting SIM_DETECT pin state of SIM card slot, so as to support SIM card hot-plugging function.
SIM card hot-plugging function can be configured by “AT+MSMPD” command, and the description of AT
command is as below:
AT Command
Detection of SIM Card
Hot-plugging Function
Function Description
AT+MSMPD=1
On
Default value, SIM card hot-plugging detection function is
on
The module detects whether SIM card is inserted or not
by detecting SIM_DETECT pin state
AT+MSMPD=0
Off
SIM card hot-plugging detection function is off
When start-up, the module reads SIM card and does not
detect SIM_DETECT state
When SIM card hot-plugging detection function is on and SIM_DETECT is at high level, the module
executes SIM card initialization program after detected SIM card inserted, and the module conducts