I2C Bus; General Purpose Input/Output (Gpio) - SimCom SIM800 Hardware Design

4.12. I2C BUS

The SIM800 provides an I2C interface. It has the following features:

Compliant master mode operation

Adjustable clock speed for LS/FS mode operation

Support 7-bit/10-bit addressing

Support high speed mode

Support slave clock extension

START/STOP/REPEATED condition

Manual transfer mode

Multi-write per transfer (up to 8 data bytes for non-DMA mode)

Multi-read per transfer (up to 8 data bytes for non-DMA mode)

Multi-transfer per transaction

Combined format transfer with length change capability

Active drive/write-and I/O configuration
Table 21: Pin definition of the I2C
Pin name
SCL
SDA
Note: I2C has been pulled up to 2.8V via 4.7KΩ inside.

4.13. General Purpose Input/Output (GPIO)

SIM800 provides 2 GPIO pins. The output voltage level of the GPIO can be set by the AT command "AT+
or "AT+CGPIO"
SGPIO"
"AT+CGPIO"
SGPIO"or
NOTE: If you use AT+SGPIO,, <GPIO> According to the following mapping
：
GPIO17 <GPIO>=3
：
GPIO19 <GPIO>=2
The Pin number table in the AT+CGPIO command under <pin> reference
Table 22: Pin definition of the GPIO
Pin name
GPIO17
GPIO19
SIM800_Hardware Design_V1.10
Pin number Description
37 I2C serial bus clock(open drain output)
38 I2C serial bus data(open drain output)
. The input voltage level of the GPIO can also be read by the AT command "AT+
. For more details, please refer to document [1].
Reset state
Pin number
11 -
13 -
44
Smart Machine Smart Decision
2018-08-13