EEE Dept Engineering Topics List

Static LED, Multiplexed

Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (e) Keyboard and Display Controller - 8279

Most of the microprocessor-controlled instruments and machines need to display letters of the alphabet and numbers to give directions or data values to users. This information can be displayed using CRT, LED or LCD displays.

Microprocessors and Microcontrollers

Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (e) Keyboard and Display Controller - 8279

1. Key Debounce using Hardware 2. Key Debouncing using Software 3. Simple Keyboard Interface 4. Matrix Keyboard Interface

Microprocessors and Microcontrollers

Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (e) Keyboard and Display Controller - 8279

In this chapter we will discuss keyboard and display interfacing in detail and study the programmable keyboard/display interface, 8279.

Serial Data Transfer (USART) 8251

Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (d) Serial Data Transfer (USART) 8251

Microprocessors and Microcontrollers: Unit IV: (d) Serial Data Transfer (USART) 8251 : Two Marks Questions with Answers, University Questions with Answers (Long Answered Questions)

Serial Data Transfer (USART) 8251

Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (d) Serial Data Transfer (USART) 8251

Review Question : 1. Explain the operation and programming of 8251 USART in detail.

Serial Data Transfer (USART) 8251

Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (d) Serial Data Transfer (USART) 8251

Review Question : 1. Explain with a neat diagram the interfacing of 8251 to 8085 microprocessor.

Serial Data Transfer (USART) 8251

Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (d) Serial Data Transfer (USART) 8251

We know that, 8251A is Universal Synchronous, Asynchronous, Receiver, and Transmitter. Therefore communication can take place with four different ways. 1. Asynchronous transmission 2. Asynchronous reception 3. Synchronous transmission 4. Synchronous reception

Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (d) Serial Data Transfer (USART) 8251

Review Questions 1. Describe the status control words in 8251. 2. Draw and explain the mode instruction and command instruction formats in 8251.

Serial Data Transfer (USART) 8251

Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (d) Serial Data Transfer (USART) 8251

The control words of 8251A are split into two formats : 1. Mode instruction 2. Command instruction

Serial Data Transfer (USART) 8251

Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (d) Serial Data Transfer (USART) 8251

Fig. 12.4.1 shows the block diagram of IC 8251A. It includes: Data bus buffer, Read/Write control logic, Modem control, Transmit buffer, Transmit control, Receiver buffer and Receiver control.

Serial Data Transfer (USART) 8251

Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (d) Serial Data Transfer (USART) 8251

Review Question : 1. Explain the important signals and 8251.

Serial Data Transfer (USART) 8251

Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (d) Serial Data Transfer (USART) 8251

Review Questions : 1. Explain the advantages of using the following chip in microprocessor based systems : USART. 2. Bring about the features of 8251.