SimCom SIM800 Series, Проектирование аппаратного обеспечения

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SIM800_Hardware Design_V1.10 44 2018-08-13
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
Note: I2C has been pulled up to 2.8V via 4.7K
Ω 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+
SGPIO”
or “AT+CGPIO”
. The input voltage level of the GPIO can also be read by the AT command “AT+
SGPIO”or
“AT+CGPIO”
. For more details, please refer to document [1].
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 Pin number
Reset state
GPIO17
11 -
GPIO19
13 -
Pin name Pin number Description
SCL 37 I2C serial bus clock(open drain output)
SDA 38 I2C serial bus data(open drain output)