(5) SPI application design and simulation verification 1 - logic sorting

         Talk to me UART It hasn't been debugged yet ... The course has arrived again SPI Of learning , Harden your head and straighten it first . After a long time of study , At least we know UART The protocol is relatively complex to use （ But the teacher said it was an entry-level agreement ）, You need to set the start bit, check bit and stop bit , And data is transmitted at most 9 position （ Remove the check bit ）. At the same time, in order to ensure the accuracy of asynchronous transmission , We need to get back and forth byte Enough space shall be reserved for transmission , The superposition of such problems leads to UART The transmission rate is greatly reduced , And the data width is limited . Is there any more advanced transmission method ？SPI Transfer protocol , It liberates the limitation of data width , Remove the trouble of asynchronous transmission , It looks great .
 UART:

SPI:

analysis ,SPI How to realize the transmission The width of input data is unlimited , No problem with asynchronous transmission Of .
         First , There is no check bit during data transmission 、 Start bit 、 Stop bit these limits , So a single set of data itself can be very long . This can be seen from the comparison of the above figure . Besides ,master and slave The same is used for data transmission SCLK, So there is no asynchronous problem .

（ One ） Module structure analysis </