40 lines
1,000 B
Markdown
40 lines
1,000 B
Markdown
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# Yet another I2C driver for the ESP8266
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This time a driver for the excellent esp-open-rtos. This is a bit banging I2C driver based on the Wikipedia pesudo C code [1].
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### Adding to your project
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Add the driver to your project as a submodule rather than cloning it:
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````
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% git submodule add https://github.com/kanflo/esp-open-rtos-driver-i2c.git i2c
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````
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The esp-open-rtos makefile-fu will make sure the driver is built.
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### Usage
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````
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#include <i2c.h>
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#define SCL_PIN (0)
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#define SDA_PIN (2)
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uint8_t slave_addr = 0x20;
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uint8_t reg_addr = 0x1f;
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uint8_t reg_data;
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uint8_t data[] = {reg_addr, 0xc8};
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i2c_init(SCL_PIN, SDA_PIN);
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// Write data to slave
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bool success = i2c_slave_write(slave_addr, data, sizeof(data));
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// Issue write to slave, sending reg_addr, followed by reading 1 byte
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success = i2c_slave_read(slave_addr, ®_addr, reg_data, 1);
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````
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The driver is released under the MIT license.
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[1] https://en.wikipedia.org/wiki/I²C#Example_of_bit-banging_the_I.C2.B2C_Master_protocol
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