Edit README

Author: MBjoern

README.md

@@ -1,35 +1,51 @@
+# Sensirion Embedded I2C SEN55 Driver
+
+This is a generic embedded driver for the Sensirion SEN55 sensor module. It enables developers to communicate with the
+SEN55 sensor module on different hardware platforms by only adapting the I2C communication related source files.
+
+<center><img src="images/SEN5x.png" width="500px"></center>
+
 # Getting started
 
+## Connecting the Sensor
+
+Your sensor has the five different connectors: VCC, GND, SDA, SCL, SEL (the sixth connector will not be used for now).
+
+<center><img src="images/SEN55_pinout.png" width="300px"></center>
+
+| *Pin* | *Name* | *Description*                   | *Comments*                            |
+|-------|--------|---------------------------------|---------------------------------------|
+| 1     | VDD    | Supply Voltage                  | 5V ±10%
+| 2     | GND    | Ground                          |
+| 3     | SDA    | I2C: Serial data input / output | TTL 5V and LVTTL 3.3V compatible
+| 4     | SCL    | I2C: Serial clock input         | TTL 5V and LVTTL 3.3V compatible
+| 5     | SEL    | Interface select                | Pull to GND to enable I2C interface
+| 6     | NC     | Do not connect                  |
+
 ## Implement the I2C Interface
 
 So we need to adjust two files according to your platform.
 
 ### Edit `sensirion_i2c_hal.c`
 
-This file contains the implementation of the sensor communication, which
-depends on your hardware platform. We provide function stubs for your
-hardware's own implementation.
-Sample implementations are available for some platforms:
-[`sample-implementations`](sample-implementations). For Linux based platforms
-like Raspberry Pi you can just replace the unimplemented HAL template with the
-implementation in `sample-implementations/linux_user_space/`:
+This file contains the implementation of the sensor communication, which depends on your hardware platform. We provide
+function stubs for your hardware's own implementation. Sample implementations are available for some platforms:
+[`sample-implementations`](sample-implementations). For Linux based platforms like Raspberry Pi you can just replace the
+unimplemented HAL template with the implementation in `sample-implementations/linux_user_space/`:
 
 ```
 cp sample-implementations/linux_user_space/sensirion_i2c_hal.c ./
 ```
 
 ### Edit `sensirion_config.h`
 
-Skip this part for Linux based platforms since everything is already setup for
-this case.
+Skip this part for Linux based platforms since everything is already setup for this case.
 
-Otherwise you need to check if the libraries `<stdint.h>` and `<stdlib.h>` are
-provided by your toolchain, compiler or system. If you have no idea on how to
-do that you can skip this step for now and come back when you get errors
-related to these names when compiling the driver.
-The features we use from those libraries are type definitions for integer sizes
-from `<stdint.h>` and `NULL` from `<stdlib.h>`. If they are not available you
-need to specify the following integer types yourself:
+Otherwise you need to check if the libraries `<stdint.h>` and `<stdlib.h>` are provided by your toolchain, compiler or
+system. If you have no idea on how to do that you can skip this step for now and come back when you get errors related
+to these names when compiling the driver. The features we use from those libraries are type definitions for integer
+sizes from `<stdint.h>` and `NULL` from `<stdlib.h>`. If they are not available you need to specify the following
+integer types yourself:
 
 * `int64_t` = signed 64bit integer
 * `uint64_t` = unsigned 64bit integer
@@ -40,55 +56,47 @@ need to specify the following integer types yourself:
 * `int8_t` = signed 8bit integer
 * `uint8_t` = unsigned 8bit integer
 
-In addition to that you will need to specify `NULL`. For both we have a
-detailed template where you just need to fill in your system specific values.
+In addition to that you will need to specify `NULL`. For both we have a detailed template where you just need to fill in
+your system specific values.
 
 Now we are ready to compile and run the example usage for your sensor.
 
 ## Compile and Run
 
-Pass the source `.c` and header `.h` files in this folder into your C compiler
-and run the resulting binary. This step may vary, depending on your platform.
-Here we demonstrate the procedure for Linux based platforms:
+Pass the source `.c` and header `.h` files in this folder into your C compiler and run the resulting binary. This step
+may vary, depending on your platform. Here we demonstrate the procedure for Linux based platforms:
 
 1. Open up a terminal.
 2. Navigate to the directory where this README is located.
 3. Run `make` (this compiles the example code into one executable binary).
-4. Run the compiled executable with `./[SENSORNAME]_i2c_example_usage`
-5. Now you should see the first measurement values appear in your terminal. As
-   a next step you can adjust the example usage file or write your own main
-   function to use the sensor.
+4. Run the compiled executable with `./sen55_i2c_example_usage`
+5. Now you should see the first measurement values appear in your terminal. As a next step you can adjust the example
+   usage file or write your own main function to use the sensor.
 
 # Background
 
 ## Files
 
 ### sensirion\_i2c.[ch]
 
-In these files you can find the implementation of the I2C protocol used by
-Sensirion sensors. The functions in these files are used by the embedded driver
-to build the correct frame out of data to be sent to the sensor or receive a
-frame of data from the sensor and convert it back to data readable by your
-machine. The functions in here calculate and check CRCs, reorder bytes for
-different byte orders and build the correct formatted frame for your sensor.
+In these files you can find the implementation of the I2C protocol used by Sensirion sensors. The functions in these
+files are used by the embedded driver to build the correct frame out of data to be sent to the sensor or receive a frame
+of data from the sensor and convert it back to data readable by your machine. The functions in here calculate and check
+CRCs, reorder bytes for different byte orders and build the correct formatted frame for your sensor.
 
 ### sensirion\_i2c\_hal.[ch]
 
-These files contain the implementation of the hardware abstraction layer used
-by Sensirion's I2C embedded drivers. This part of the code is specific to the
-underlying hardware platform. This is an unimplemented template for the user to
-implement. In the `sample-implementations/` folder we provide implementations
-for the most common platforms.
+These files contain the implementation of the hardware abstraction layer used by Sensirion's I2C embedded drivers. This
+part of the code is specific to the underlying hardware platform. This is an unimplemented template for the user to
+implement. In the `sample-implementations/` folder we provide implementations for the most common platforms.
 
 ### sensirion\_config.h
 
-In this file we keep all the included libraries for our drivers and global
-defines. Next to `sensirion_i2c_hal.c` *it's the only file you should need to
-edit to get your driver working.*
+In this file we keep all the included libraries for our drivers and global defines. Next to `sensirion_i2c_hal.c` *it's
+the only file you should need to edit to get your driver working.*
 
 ### sensirion\_common.[ch]
 
-In these files you can find some helper functions used by Sensirion's embedded
-drivers. It mostly contains byte order conversions for different variable
-types. These functions are also used by the UART embedded drivers therefore
-they are kept in their own file.
+In these files you can find some helper functions used by Sensirion's embedded drivers. It mostly contains byte order
+conversions for different variable types. These functions are also used by the UART embedded drivers therefore they are
+kept in their own file.