30 lines
1 KiB
Markdown
30 lines
1 KiB
Markdown
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# I2C Example
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* This example will show you how to use I2C module by running two tasks on i2c bus:
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* read external i2c sensor, here we use a BH1750 light sensor(GY-30 module) for instance.
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* Use one I2C port(master mode) to read or write the other I2C port(slave mode) on one ESP32 chip.
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* Pin assignment:
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* slave :
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* GPIO25 is assigned as the data signal of i2c slave port
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* GPIO26 is assigned as the clock signal of i2c slave port
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* master:
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* GPIO18 is assigned as the data signal of i2c master port
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* GPIO19 is assigned as the clock signal of i2c master port
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* Connection:
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* connect GPIO18 with GPIO25
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* connect GPIO19 with GPIO26
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* connect sda/scl of sensor with GPIO18/GPIO19
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* no need to add external pull-up resistors, driver will enable internal pull-up resistors.
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* Test items:
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* read the sensor data, if connected.
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* i2c master(ESP32) will write data to i2c slave(ESP32).
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* i2c master(ESP32) will read data from i2c slave(ESP32).
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