The UART is also responsible for baud rate generation. This means that there is no master clock used for timing data transfer between devices.

UART communications is asynchronous (i.e. Binary 0: UART: 0V RS232: 3-25V Binary 1: UART: 5V RS232 -3V to -25VĨ UART communications is asynchronous (i. For noise immunity and transmission length, the RS232 standard dictates the transmission of bits at a higher voltage range and different polarities (i.e. The UART operates at TTL voltage levels (i.e. In practice, it’s a little more complicated, but that’s the basic idea.Ħ The UART, however, doesn’t operate at the line voltages required by the RS232 standard. Likewise, the UART receives serialized bits and converts them back into bytes. The UART is responsible for breaking apart bytes of data and transmitting it one bit at a time (i.e. This circuitry is built in to the 8051 microcontroller. It is the interface circuitry between the microprocessor and the serial port. UART (pronounced “You Art”) is an industry acronym that stands for Universal Asynchronous Receiver Transmitter. To accomplish the necessary translation between bytes and bits, another piece of hardware is required – the UART. In our C programs though, we read and write bytes to the serial port – not bits. When we talk about serial communications, what do we really mean? How is the data transmitted? Serial data is transmitted between devices one bit at a time using agreed upon electrical signals. It is usually listed on the datasheet as UART. An RS232 serial port is included on most 8051 microcontrollers.

Multi-master communications.Ĥ The Silicon Laboratories 8051 development kit used in this book supports RS232, SPI and I2C communications. I2C (Inter-Integrated Circuit).Developed by Philips.

communications between two or more devices) USB (Universal Serial Bus). communications between two devices) RS485. Introduce software and hardware handshaking.ģ Introduction There are several popular types of serial communications. Objectives Introduce the RS232 standard and position it within the crowded field of serial communications standards. Presentation on theme: 'Chapter 6 Serial Communications'- Presentation transcript:

Serial communication types