Three Different Ways of Communication (SPI, I2C, USART) Adopted on RF Modules

Generally, there are three different communication modes adopted on the RF modules, namely SPI (Serial Peripheral Interface), I2C (Inter-Integrated Circuit), USART (Universal Synchronous/Asynchronous Receiver/Transmitter). Below is the details for your reference:

1.  SPI: The full name of SPI is Serial Peripheral Interface, it is characterized by full duplex operation, synchronization and high-speed transmission. With this kind of communication, there is usually one host and many slaves working together. If it is two-way transmission, four lines are needed, namely SDI (data input), SDO (data output), SCLK (clock), CS (chip selection). Therefore, when communicating in this way, there are usually many slave devices, such as human-computer interface.

2.  I2C: The full name of I2C is Inter-Integrated Circuit, which is a serial bus mode. It only needs two lines to communicate, one is the data line (SDA), the other is the clock line (SCL). This kind of communication way is that the host and the slave are not clearly distinguished, but there can only be one host during the working time. As to which one can be used, depending on the way the circuit actually works, in general, both lines need to add pull-down or pull-down resistance in order to strengthen the anti-jamming ability; at the same time, two capacitors need to be added to the ground. Because only two wires are needed in this way, this connection method is widely used, especially on small products such as home appliances and medical treatment.

3.  USART: The full name of USART is Universal Synchronous/Asynchronous Receiver/Transmitter. It is a full duplex serial receiving and transmitting module. It requires data transmitter, receiver and clock generator to work. It works in a flexible way, which is often used in SMT chips, computer to TV connection and so on in our daily life.

You can choose the appropriate RF module according to your own needs, as well as the correct interface type. If you need any help, please feel free to contact us!