Different between UART & USART
UART vs USART
UART and USART are both serial communication protocols, but they differ in some key ways.
UART stands for Universal Asynchronous Receiver/Transmitter. It is a simple and efficient protocol for transmitting data serially over a single wire. UART is typically used for low-speed communication, such as connecting a computer to a modem or a microcontroller to a sensor.
USART stands for Universal Synchronous/Asynchronous Receiver/Transmitter. It is a superset of UART, meaning that it supports all of the same features as UART, plus additional features for synchronous communication. Synchronous communication uses a clock signal to synchronize the transmission of data between the sender and receiver. This makes synchronous communication more reliable than asynchronous communication, but it also requires more complex circuitry.
USART is typically used for high-speed communication, such as connecting a computer to a printer or a microcontroller to a network device.
Here is a table that summarizes the key differences between UART and USART:
| Feature | UART | USART |
|---|---|---|
| Communication mode | Asynchronous | Asynchronous or synchronous |
| Data rate | Up to 115,200 bps | Up to several Mbps |
| Clock signal | Not required | Required for synchronous communication |
| Complexity | Less complex | More complex |
| Common applications | Low-speed communication, such as connecting a computer to a modem or a microcontroller to a sensor | High-speed communication, such as connecting a computer to a printer or a microcontroller to a network device |
Which one should you use?
If you need a simple and efficient way to transmit data serially at a low speed, then UART is a good choice. If you need to transmit data serially at a high speed or need to use synchronous communication, then USART is a better choice.
Most modern microcontrollers have a USART peripheral, so you don't need to worry about choosing between UART and USART. You can simply use the USART peripheral to support both asynchronous and synchronous communication.
In short:
USART :Universal Synchronous/Asynchronous Receiver/Transmitter
- Half-duplex mode is used for transmission & reception of data.
- Speed of USART is more as compared to UART.
- USART uses data signals along with clocks.
- The data is tranmitted in the form of blocks.
- The receiver dosen`t require to know the baud rate of transmitter, because it gets information by the master and clock signal.
- The data is transmitted at definite (specific) rate.
- For example RS-232
UART :Universal Asynchronous Receiver/Transmitter
- Full-duplex mode is used for transmission of data.
- Speed of UART is less as compared to USART.
- It used data signals for functioning (as it is asychronous communication protocol).
- Data is transmitted using bytes, one byte at a time.
- UART dosen`t have an approching clock signal which would be related to information, i.e. in UART communication receipient is required to know baud rate of transmitter before gathering.
- The data can be transmitted at varying speed.
- For example GPS