Introduction to Universal Asynchronous Receiver-Transmitter (UART)
The UART interface is one of the oldest interfaces still active and in use. It was developed in the 1960s by Digital Equipment Corporation for its PDP-1 minicomputer.
Figure 12.2: Serial connection between a computer and test equipment
Today it is used as a debug port from televisions to test equipment. It’s commonly used to communicate with embedded processors like the Microblaze that we will use in Chapter 13, Embedded Microcontrollers using the Xilinx MicroBlaze.
Let’s take a look at the physical connections of the UART bus.
Bus interface
The UART interface is a slow speed compared to modern-day interfaces. Current serial interfaces such as USB or PCIe lanes can be multiple gigabits per second. UART is a serial interface that can be run in full duplex where data is sent and received simultaneously, or half duplex where RX and TX do not run at the same time. In the design we...
