How 8255 programmable peripheral interface can operate, Electrical Engineering

Assignment Help:

What are the different modes in which 8255 Programmable Peripheral Interface (PPI) can operate?

Twenty Four I/O lines in 38-bit port groups - A, B and C
A and B can be 8-bit input/output ports
C can serve as twenty four-bit input /output ports
3 modes of operation:

- Mode 0: A, B, C simple input / output level sensitive ports

- Mode 1: A, B input / output ports along with strobe control in C

- Mode 2: A is bidirectional along with control/handshake in B and C

A, B can only modify 1 byte at a time
C has individual bit set/reset ability
Improvement is non-dedicated circuit can change port configuration along with software and no "glue logic"
Ports A, B and C are utilized for I/O data.
The control register is programmed to choose the operation mode of the three ports A, B and C.
Mode 0: simple I/O mode
Any of the ports A, B, CL and CU can be programmed as input / output.
No control of individual bits (all bits are out or in

Related Discussions:- How 8255 programmable peripheral interface can operate

Explain polyphase induction motor, Q. Explain polyphase induction motor? ...

Q. Explain polyphase induction motor? The polyphase induction motor operates with polyphase alternating current applied to the primary winding, usually located on the stator of

Ujt as a relaxation oscillator , UJT as a relaxation oscillator Th...

UJT as a relaxation oscillator The UJT is a highly efficient switch it is used as trigger a device for SCR. No sinusoidal oscillators saw tooth generators phase contro

Power Engineering, A three-phase transposed line is composed of one ACSR co...

A three-phase transposed line is composed of one ACSR conductor per phase with flat horizontal spacing of 11 meters as shown in Figure (a). The conductors have a diameter of 3.625

Explain limit signal spectrum to prevent aliasing, Explain Limit Signal Spe...

Explain Limit Signal Spectrum to Prevent Aliasing? The sampling frequency should at least be two times that of the highest frequency in the incoming signal to avoid aliasing. T

Antinoise systems — noise cancellation, Q. Antinoise Systems — Noise Cancel...

Q. Antinoise Systems — Noise Cancellation? Traditionally sound-absorbing materials have been used quite effectively to reduce noise levels in aircraft, amphitheaters, and other

Explain cache structure in pentium, Explain cache structure in Pentium. ...

Explain cache structure in Pentium. Cache structure in Pentium: The cache in the Pentium has been changed by the one determined in the 80486 microprocessor. The Pentium has t

Quantizer, Q. When the quantum step size δv and the step size of f (t) are ...

Q. When the quantum step size δv and the step size of f (t) are the same as in , the quantizer is said to have a gain of unity. If, on the other hand, the quantizer has a gain of K

What is idss, Q. What is Idss. What are the conditions for its maximum valu...

Q. What is Idss. What are the conditions for its maximum value? The term 'Idss' refers to saturation condition of the Drain current. From the above graph it's clear that as the

Adaptive control process in motor-speed control system, Q. Adaptive control...

Q. Adaptive control process in motor-speed control system? Figure illustrates the adaptive control process as applied to a motor-speed control system, which is based on adjus

Explain about zener diodes, Q. Explain about Zener Diodes? Most diodes ...

Q. Explain about Zener Diodes? Most diodes are not intended to be operated in the reverse breakdown region. Diodes designed expressly to operate in the breakdown region are cal

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages