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SIM900-DS_Hardware Design_V1.00
31
2013-01-20
Figure 28: Molex 91228 SIM card holder
Table 9: Pin description (Molex SIM card holder)
Pin name
Signal
Description
C1
SIM_VDD
SIM card power supply
C2
SIM_RST
SIM card reset
C3
SIM_CLK
SIM card clock
C4
GND
Connect to GND
C5
GND
Connect to GND
C6
VPP
Not connect
C7
SIM_DATA
SIM card data I/O
C8
SIM_PRESENCE
Detect SIM card presence
4.8
LCD Display/SPI Interface
SIM900-DS provides a serial LCD display interface. It could also be used as SPI interface in the embedded AT
application. For details about embedded AT application, please refer to
document [7].
Note: This function is not supported in the standard firmware. If user wants this function, the firmware must be customized.
Please contact SIMCom for more details.