Pic software spi slave

They are not needed in the polled driver since this driver blocks until the operation has completed. This allows the exchange byte function to work seamlessly with the exchange, receive and transmit block functions. Registering a NULL pointer as callback causes no callback function to be called.

NULL is the default value of the callback function pointer. The parameters controlled by a configuration depends on the underlying hardware the SPI Basic driver uses. Different configurations allows the SPI to use one setup when communicating with one SPI slave, and another configuration when communicating with another slave.

These calls would reconfigure the SPI hardware appropriately. The user can provide additional configurations by modifying spi. In this case the user must select which one to use. 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. As always begin the program by setting the configuration bits and then it is very important to add the header file that we just explained into the program as shown below. If you have opened the program from the zip file downloaded above then by default the header file will be present inside the header file directory of your project file.

Else you have to add the header file manually inside your project, once added your project files will look like this below. Inside the main file we have to initialize the PIC as Master for SPI communication and then inside an infinite while loop we will write random three hex values into the SPI bus to check if we receive the same during simulation. Notice that the random values used in the program are 0A, 0F and 15 and they are hex values so we should see the same during simulation.

That is it the code is all done, this is just a sample but we can use the same methodology to communicate with other MCU or with other sensors module operating on SPI protocol.

Now that our program is ready we can compile it and then proceed with simulation. So we use the same and build a circuit like shown below. Since there is only one SPI device in the simulation we are not using the SS pin and when not used it should be grounded as shown above. Just load the hex file into the PIC16FA microcontroller and click on the play button to simulate our program.

Actually with some modification first method worked.. Thanks anyways. Latest Posts. U instruction A little insight with writing relocatable code please. Active Posts. Is XC16 not as good? All FAQs. Why does my PIC32 run slower than expected? Stay logged in. ThankYou 1 5 Replies Related Threads. Thanks anyways 6.