96 lines
2.6 KiB
Markdown
96 lines
2.6 KiB
Markdown
# I2C BB
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I2C bitbang gpio driver.
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## Installation
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```shell
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make install
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```
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Installs `libi2c_bb.a` and `libi2c_bb.so` in the directory `$(PREFIX)/lib/`. It also installs the include header file `i2c.h` in the directory `$(PREFIX)/include/i2c_bb/`. The default value for `PREFIX` is: `PREFIX=usr`. To use another location for installation changing the value of the `PREFIX` variable is needed. E.g.:
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```shell
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PREFIX=/usr/local/ make install
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```
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## Uninstallation
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```shell
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make install
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```
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Removes the files installed with the `install` make target.
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> **NOTE:** If `PREFIX` variable was changed during installation process the same value needs to be set for uninstallation. E.g.:
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```shell
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PREFIX=/usr/local/ make install
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```
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## Example
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```C
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <syslog.h>
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#include <stdbool.h>
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#include <i2c_bb/i2c.h>
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#define I2C_SLAVE_ADDR 0x48
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#define BUFFER_SIZE 3
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const static struct i2c_bb i2c_dev = {
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.pin_sda = 4,
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.pin_scl = 24,
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};
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int main(void)
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{
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int res;
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char buffer[BUFFER_SIZE]
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openlog("i2c_bb", LOG_CONS | LOG_PID | LOG_NDELAY, LOG_LOCAL1);
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res = i2c_open(&i2c_dev);
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if(res != EXIT_SUCCESS) {
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syslog(LOG_ERR, "Unable to open i2c device.\n");
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return res;
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}
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buffer[0] = 0x01;
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buffer[1] = 0xc1;
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buffer[2] = 0x87;
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// Write to register address 0x01 value 0xc187:
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i2c_write(&i2c_dev, I2C_SLAVE_ADDR, buffer, BUFFER_SIZE);
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buffer[0] = 0x00;
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// Set register address 0x00:
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i2c_write(&i2c_dev, addr, buffer, 1);
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// Read from register 0x00 two bytes:
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i2c_read(&i2c_dev, I2C_SLAVE_ADDR, buffer, 2);
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i2c_close(&i2c_dev);
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return EXIT_SUCCESS;
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}
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```
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## Additional make targets
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| Target | Meaning |
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| --------------- | ----------------------------------------------------------- |
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| all | Build the code, assemble the static and shared library. |
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| install | Install the libraries and necessary include header files. |
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| uninstall | Uninstall the libraries and necessary include header files. |
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| clean | Clean up build artifacts. |
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| distclean | Remove all folders created during any build step. |
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| build_unit_test | Build the unit tests. |
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| exec_unit_test | Execute the unit tests. |
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| coverage | Determine code coverage of the unit tests. |
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| check | Static code analysis (cppcheck). |
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