Operating Status Indication; Status Multiplexing Function; Rf Synchronization Signal; Rf_Sync Multiplexing Function - SimCom SIM800C Hardware Design

4.11. Operating Status Indication

The pin42 is for operating status indication of the module. The pin output is high when module is powered on,
and output is low when module is powered off.
Table 23: Pin definition of the STATUS
Pin name
STATUS
Note: For timing about STATUS, please reference to the chapter "4.2 power on/down scenarios"

4.11.1. STATUS Multiplexing Function

Table 24: STATUS multiplexing function
Pin name Pin number
STATUS 42
Note: Multiplexing function need different software supply.

4.12. RF Synchronization Signal

The synchronization signal is used to indicate incoming GSM burst.
Table 25: Definition of the RF_SYNC pin
Pin name
RF_SYNC
The timing of the synchronization signal is shown below.

4.12.1. RF_SYNC Multiplexing Function

RF_SYNC can also be used as GPIO to indicate the RF Jamming. The RF_SYNC function and RF Jamming
Detection function can be switched by AT+SJDR command.
Table 26: RF_SYNC Multiplexing function
SIM800C_Hardware_Design_V1.02
Pin number Description
42 Operating status indication
Mode 0(default)
STATUS
Pin number Description
29 Transmit synchronization signal
220us
T ransm i t burst
R F _S Y N C
Figure 35: RF_SYNC signal during transmit burst
Mode 1
GPIO
577us
36
Smart Machine Smart Decision
2015-4-27