SimCom SIM800H, Hardware Design Manual

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Table 23: Pin definition of the keypad interface
Pin name Pin number Function Default state
COL0 20 Pull up
COL1 25 Pull down
COL2 22 Pull down
COL3 21 Pull down
COL4 24
Keypad matrix column
Pull down
ROW0 62 Pull down
ROW1 60 Pull down
ROW2 61 Pull down
ROW3 23 Pull down
ROW4 63
Keypad matrix row
Pull down
4.10.1. Keypad Multiplexing Function
Table 24: Keypad multiplexing function
Pin name Pin number Mode 0(default) Mode 1
COL0 20 COL0 GPIO6
COL1 25 COL1 GPIO7
COL2 22 COL2 GPIO8
COL3 21 COL3 GPIO9
COL4 24 COL4 GPIO10
ROW0 62 ROW0 GPIO11
ROW1 60 ROW1 GPIO12
ROW2 61 ROW2 GPIO13
ROW3 23 ROW3 GPIO14
ROW4 63 ROW4 GPIO15
Note: Multiplexing function need different software supply.
4.11. I2C Bus
The SIM800H provides an I
2
C interface which is only used in the embedded AT application.
Table 25: Pin definition of the I
2
C
Pin name Pin number Description
SCL 74 I
2
C serial bus clock
SDA 75 I
2
C serial bus data
Notes:
1.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.
2.If user design I
2
C please pull up to VDD_EXT.
SIM800H_Hardware_Design_V1.01
47
2013-08-20