This in can be used to select the required slave. A sample circuit where more than one slave is connected with the master for SPI communication is shown in the circuit below. The reason is both I2C and SPI communications are advantages in its own ways and hence is application specific. To an extent the I2C communication can be considered to have some advantages over SPI communication because I2C uses less number of pin and it gets very handy when there are a large number of slaves connected to the bus.
But the drawback of I2C is that it has the same bus for sending and receiving data and hence it is comparatively slow. Before we start make it clear that this tutorial only talks about SPI in PIC16Fa using XC8 compiler , the process will be the same for other microcontrollers but slight changes might be required. The library explained here will be given as a header file for download at the bottom which can be used for PIC16FA to communicate with other SPI devices.
We will then verify the same using Proteus simulation. This way we can use this header file in all our upcoming projects in which SPI communication is required. And inside the main program we will just use the functions from the header file. The complete code along with the header file can be downloaded from here. You can read more about them on page 74 and 75 of the datasheet. There are many parameters options that has to be chosen while initializing the SPI communication.
So we are also using the same configuration for our header file, you can easily change them by changing the respective bits. Inside this function we set the respective pins RC5 and RC3 as output pins. This function is used to set the microcontroller to work in slave mode for SPI communication.
During slave mode the pin RC5 should be set as output and the pin RC3 should be set as input. It gets the information from the user through the variable incoming and then uses it to pass to the Buffer register. The SSPSTAT register has a bit called BF which will set once the data has been received completely, so we check if this bit is set if it is not set then we have to wait till it gets set to read anything from the SPI bus.
The functions explained in the above section will be in the header file and they can be called into the main c file. We will just write few data into the SPI bus and use the proteus simulation to check if the same data is being received in the SPI debugger. The number of sections. This indicates the size of the section table, which immediately follows the headers.
Note that the Windows loader limits the number of sections to The low 32 bits of the time stamp of the image. This represents the date and time the image was created by the linker.
The value is represented in the number of seconds elapsed since midnight , January 1, , Universal Coordinated Time, according to the system clock. ImageHlp Structures. Skip to main content. The output from the preprocessor contains the output already generated, followed by the output resulting from the included file, followed by the output that comes from the text after the include directive.
For example, if you have a header file header. If a header file happens to be included twice, the compiler will process its contents twice and it will result in an error. This construct is commonly known as a wrapper ifndef. The preprocessor will skip over the entire contents of the file, and the compiler will not see it twice.
Sometimes it is necessary to select one of the several different header files to be included into your program. For instance, they might specify configuration parameters to be used on different sorts of operating systems.
But as it grows, it becomes tedious, instead the preprocessor offers the ability to use a macro for the header name.
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