Contents
How to implement full duplex SPI communication using SPI DMA mode?
STM32F401RE supports up to 4 SPIs but SPI1 is selected for SPI communication. Additional concepts like Channel and Stream are used in the enhanced DMA mechanism. The DMA Channel and Stream is decided upon which SPI peripheral is selected.
What are the three signal wires of SPI?
Its three signal wires hold a clock (SCK, often in the range of 1-20 MHz), a “Master Out, Slave In” (MOSI) data line, and a “Master In, Slave Out” (MISO) data line. SPI is a full duplex protocol; for each bit shifted out the MOSI line (one per clock) another is shifted in on the MISO line.
What do you need to know about STM32 SPI?
STM32 SPI DMA Mode HAL Functions 1. Introduction To SPI Communication SPI is an acronym for (Serial Peripheral Interface) pronounced as “S-P-I” or “Spy”. Which is an interface bus typically used for serial communication between microcomputer systems and other devices, memories, and sensors.
What is a Serial Peripheral Interface ( SPI )?
SPI is the “Serial Peripheral Interface”, widely used with embedded systems because it is a simple and efficient interface: basically a multiplexed shift register. Its three signal wires hold a clock (SCK, often in the range of 1-20 MHz), a “Master Out, Slave In” (MOSI) data line, and a “Master In, Slave Out” (MISO) data line.
How does STM32 MCU improve SPI throughput?
STM32 MCU provides a method to enhance the SPI communication throughput by eliminating idle time between SPI read/write operations. It is SPI DMA mode. Figure 2 shows that transmission and reception of block data is done continuously without any idle time when you use SPI DMA mode. Figure2.
What are the two parameters of the SPI clock?
The SPI clock has two more parameters to control which are the Clock Phase (CPHA) and the Clock Polarity (CPOL). The clock phase determines the phase at which the data latching occurs at each bit transfer whether it’s the leading edge or the trailing edge. The clock polarity determines the IDLE state of the clock line whether it’s a HIGH or LOW.
What can a DMA controller be used for?
DMA controllers allow us to offload certain types of data shuffling from the main processor, freeing it to get on with business. In the STM32F0 series, the controller can be used to move data between two peripherals, from a peripheral into memory, or from memory to a peripheral.