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

Phenomenon - fet operation, Phenomenon - Fet operation: For either imp...

Phenomenon - Fet operation: For either improvement- or depletion-mode devices, at drain-to-source voltages very much less than gate-to-source voltages, changing the gate volta

What is the use of latch signal on the ad0-ad15 bus, What is the use of l...

What is the use of latch signal on the AD0-AD15 bus in an 8086 system? Latch signal is used to load the data those are fetched from memory to bus.

Schematic symbols, Schematic Symbols The junction gate field-effect t...

Schematic Symbols The junction gate field-effect transistor or JFET gate is sometimes drawn in the middle of the channel (in place of at the drain or source electrode as in t

What is the significance of negative voltage, Q. What is the significance o...

Q. What is the significance of giving a negative voltage to the gate higher than that of the source? This is done to reach the saturation at a lower of level of V DS . The re

Stator voltage control methods - motor control , Stator Voltage Control Met...

Stator Voltage Control Methods By controlling the applied voltage the speed of an induction motor can be controlled. Since the output torque of 3-? induction motor i

Calculate efficiency to load at unity power factor, Q. A 300-kVA transforme...

Q. A 300-kVA transformer has a core loss of 1.5 kW and a full-load copper loss of 4.5 kW. (a) Calculate its efficiency corresponding to 25, 50, 75, 100, and 125% loads at unity

Explain ferrites and its uses in high frequency devices, Explain ferrites a...

Explain ferrites and its uses in high frequency devices. A group of magnetic alloys show the property of magnetisation that change, with percentage of various constituent atoms

Short note on types of enclosure of machine, Q. Write a short note on typ...

Q. Write a short note on types of enclosure of machine. Sol. The various types of d.c. machine : (1) Magnetic frame or Yoke (2)

Determine the stations visual-carrier frequency, If a television station op...

If a television station operates on UHF channel 20 (band 506-512 MHz), determine the station's visual-carrier frequency.

Fm broadcast system with standard emphasis, Q. A voice message with W f = ...

Q. A voice message with W f = 2π(3×10 3 ) rad/s and Wrms = 2π(1 × 10 3 ) rad/s is transmitted over an FM broadcast system with standard emphasis. and compare the improvements due

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages