Smart Machine Smart Decision
2. If customers design I2C please pull up to VDD_EXT.
4.11.1. I2C Multiplexing Function
Table 26: I2C multiplexing function
Pin name
Pin number
Mode 0(default)
Mode 1
SCL
74
SCL
GPIO25
SDA
75
SDA
GPIO26
Note: Multiplexing function need different software supply.
4.12. General Purpose Input/Output (GPIO)
SIM800H&SIM800L provides 3 GPIO pins. The output voltage level of the GPIO can be set by AT command
“AT+SGPIO”. The input voltage level of the GPIO can also be read by AT command “AT+SGPIO”. For more
details, please refer to
document [1].
Table 27: Pin definition of the GPIO
Pin name
Pin number
Reset state
GPIO1
3
-
GPIO2
27
-
GPIO3
28
-
0.29s
PWRKEY
(INPUT)
SIM800H&SIM800L_Hardware Design_V2.02 47
2015-07-27
GPIO1
t<1.9s
GPIO2
0.8s
GPIO3
t<=10us
