Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (b) Programmable Interrupt Controller (PIC) - 8259
Review Questions : 1. Draw and explain the interfacing of 8259 with 8085. 2. How 8259 is interfaced with 8085 or 8051 ?
Microprocessors and Microcontrollers
Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (b) Programmable Interrupt Controller (PIC) - 8259
The 8259A requires two types of command words. Initialization Command Words (ICWs) and Operational Command Words (OCWs). The 8259A can be initialized with four ICWs; the first two are compulsory, and the other two are optional based on the modes being used.
Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (b) Programmable Interrupt Controller (PIC) - 8259
The various modes of operation of the 8259 are : 1. Fully Nested Mode, 2. Special Fully Nested Mode (SFNM) 3. Rotating Priority Mode, 4. Special Masked Mode, and 5. Polled Mode.
Programmable Interrupt Controller (PIC) - 8259
Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (b) Programmable Interrupt Controller (PIC) - 8259
Review Question : 1. Explain the processing of interrupt using 8259.
Programmable Interrupt Controller (PIC) - 8259
Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (b) Programmable Interrupt Controller (PIC) - 8259
Fig. 9.3.1 shows the internal block diagram of the 8259A. It includes eight blocks: data bus buffer, read/write logic, control logic, three registers (IRR, ISR and IMR), priority resolver, and cascade buffer.
Programmable Interrupt Controller (PIC) - 8259
Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (b) Programmable Interrupt Controller (PIC) - 8259
It can manage eight priority interrupts. This is equivalent to providing eight interrupt pins on the processor in place of INTR pin.
Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (b) Programmable Interrupt Controller (PIC) - 8259
Review Question : 1. List the interrupt related signals of 8085 that are connected to 8259 IC.
Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (b) Programmable Interrupt Controller (PIC) - 8259
Microprocessors and Microcontrollers: Unit IV: (b) Programmable Interrupt Controller (PIC) - 8259 : (b) Programmable Interrupt Controller (PIC) - 8259
Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (a) Programmable Peripheral Interface (PPI) - 8255
Microprocessors and Microcontrollers: Unit IV: (a) Programmable Peripheral Interface (PPI) - 8255 : Two Marks Questions with Answers, University Questions with Answers (Long Answered Questions)
Microprocessors and Microcontrollers
Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (a) Programmable Peripheral Interface (PPI) - 8255
The Fig. 8.8.1 shows a block diagram to implement the bidirectional communication between the master and the slave processors.
Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (a) Programmable Peripheral Interface (PPI) - 8255
Review Question : 1. Explain how the 8255 A programmable peripheral interface chip can be used with the 8085 microprocessor for reading and writing parallel data from and to I/O devices.
Microprocessors and Microcontrollers
Subject and UNIT: Microprocessors and Microcontrollers: Unit IV: (a) Programmable Peripheral Interface (PPI) - 8255
1. Programming in Mode 0 2. Programming in Mode 1 (Input / Output with Handshake) 3. Programming in Mode 2 (Strobes Bi-directional Bus I/O)