Microprocessors and Microcontrollers: Unit IV: (b) Programmable Interrupt Controller (PIC) - 8259
8259A Programmable Interrupt Controller
Review Question : 1. List the interrupt related signals of 8085 that are connected to 8259 IC.
8259A Programmable Interrupt Controller
AU
: June-11
Interrupts
can be used for a variety of applications. Each of these interrupt applications
requires a separate interrupt input. If we are working with an 8085
microprocessor we get TRAP, RST7.5, RST6.5, RST5.5, and INTR interrupt inputs.
For applications where we have multiple interrupt sources (more than five), we
have to use external device called a Priority Interrupt Controller (PIC). By
connecting such a device it is possible to increase the interrupt handling
capacity of the microprocessor. Fig. 9.1.1 shows the connection between 8085
and 8259A. The 8259A is a commonly used priority interrupt controller, which is
specifically designed for use with interrupt signals INTR and 
of Intel
series. It is packaged in a 28 pin DIP. It uses NMOS technology and requires a
single + 5 V supply.
Review Question
1. List the interrupt
related signals of 8085 that are connected to 8259 IC.
Microprocessors and Microcontrollers: Unit IV: (b) Programmable Interrupt Controller (PIC) - 8259 : Tag: : - 8259A Programmable Interrupt Controller