Technology Introduction: Communications Protocols SPI, I2C, I2S. Comparatively, SPI communication speed is quite fast and it … This is not possible in the case of SPI. For example, in STM32F4xx, if the peripheral clock of 40MHz then in I2C data rate is 400Kbps and an SPI data rate is 20Mbps. Comparing to the SPI, the data transfer speed of I2C is limited to a few Mhz. The big difference between SPI and I2C is that SPI uses a few more wires, in particular an explicit data input and data output wire instead of sharing a single data wire like with I2C. Your email address will not be published. If CPHA is 0, data is transferred to the rising clock edge. Master in, slave out (MISO)The device that generates the clock signal is called the master. I2C is less susceptible to noise than SPI. Everything from 8-bit to 32-bit MCUs will use at least one of these protocols alongside GPIOs for programmability and sending signals to simple peripherals. Draws less power as compared to I2C. I think you’ve got to learn some information from this post, but let me tell you a little difference that’s going to help you determine which one you need. On the other hand SPI can only work with one master device controlling multiple slaves. In a communication network slave selection is a mechanism initiated by master node to select a slave node for reception of the current data packet. It is also called as I2C. Forums. This arrangement makes I2C quite complex compare to the SPI. Additionally, the power supply must be connected via a pull-up resistor. 4-wire SPI devices have four signals: 1. Depending on the values for clock polarity (CPOL) and clock phase (CPHA), there are 4 SPI modes: modes 0 to 4. I'm specialized in Software development for Embedded System for domains such as Automotive & Power Tools and proficient in C, C++ & Python programming language. So this is about the similarities between I2C and SPI. I2C draws more power than SPI. All but the simplest of electronic products are likely to use multiple Integrated Circuits (also known as ICs or simply ‘chips’) in their design. If you want to send data at a higher speed, SPI is a better choice. Efficient, because it allows multiple master multiple slave communication. They are both bidirectional and open-collector. Clock (SPI CLK, SCLK) 2. The master then selects the desired slave for communication by switching the slave peripheral (SS) selection chip to a “low” state and activating the specific slave whom the master wants to communicate by using the slave selection (SS). The master and slave really have to decide on certain protocols for synchronization. The SPI protocol, or serial peripheral interface, is another example of a serial protocol for two devices to send and receive data. One significant difference is the I2C is mucher slower (typically 100-400KHz, maximum 5 MHz) as compared to SPI, which can go up to 80MHz or sometimes even higher speed. It only depends on the direction of the data at the time. Its primary purpose was to provide a convenient way to connect a CPU to peripheral chips on a TV set. DCUBE TECH VENTURES SPI is used to send data between the microcontroller(master) and peripheral devices(slaves) such as shift registers, sensors, etc. SPI devices support much higher clock frequencies compared to I2C interfaces. SPI needs 4 lines, but I2C needs also 3 lines! on Google+. If the master decides to transmit the data to the slave then before sending any data, the master must first address the slave. I know i2c is more complex slow than spi uart etc. The other line is the SDA line that is used to send the data. For example applications like: And SPI is protocol is or the applications where a number of bytes per transaction are quite high and a high-speed communication protocol is required. https://www.youtube.com/watch?v=4GcggYQYrXU. 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