The 8259A Programmable Interrupt Controller (PIC) handles prioritized interrupt requests from peripherals for the CPU. It accepts up to 8 interrupt requests, determines priority, and issues an interrupt to the CPU. It can be programmed and cascaded to handle more interrupts. The PIC includes registers to store incoming requests, mask bits, and service status. It uses initialization and operation command words to configure operation and interact with the CPU through control signals and data bus.
PIC A special purpose integrated circuit that function as an overall manager in an interrupt driven system.
It accepts request from the peripheral equipment,determines which of the incoming request is of the highest priority, ascertains whether the incoming request has a higher priority value than the level currently being serviced, and issues an interrupt to the CPU based on this determination.
PIC A special purpose integrated circuit that function as an overall manager in an interrupt driven system.
It accepts request from the peripheral equipment,determines which of the incoming request is of the highest priority, ascertains whether the incoming request has a higher priority value than the level currently being serviced, and issues an interrupt to the CPU based on this determination.
found this one in one of my abandoned folders. AC(students from JUCSE need no introduction but for others you should never want to know him :-O) assigned this task to me and 3 of my fellow classmates to create a presentation on this uninteresting and weird topic. We pulled it off however :P
Complete description of AT89xxx (8051 based) microcontrollers with timers, serial communication and assembly language programming. Interfacing of some real time devices like led, sensor, and seven segment display is also covered.
this is the brief description of the 8085 microprocessor. in this ppt, I described the key features of 8085, architecture, pin diagram, interfacing, timing diagram, some program, etc. I have also discussed the memory interfacing of 8085 microprocessor.
This presentation discusses the support for interrupts in 8051. The interrupt types, interrupts versus polling etc are discussed. The register formats of IE, IP register are discussed. The concept of priority among the interrupts is discussed.
found this one in one of my abandoned folders. AC(students from JUCSE need no introduction but for others you should never want to know him :-O) assigned this task to me and 3 of my fellow classmates to create a presentation on this uninteresting and weird topic. We pulled it off however :P
Complete description of AT89xxx (8051 based) microcontrollers with timers, serial communication and assembly language programming. Interfacing of some real time devices like led, sensor, and seven segment display is also covered.
this is the brief description of the 8085 microprocessor. in this ppt, I described the key features of 8085, architecture, pin diagram, interfacing, timing diagram, some program, etc. I have also discussed the memory interfacing of 8085 microprocessor.
This presentation discusses the support for interrupts in 8051. The interrupt types, interrupts versus polling etc are discussed. The register formats of IE, IP register are discussed. The concept of priority among the interrupts is discussed.
Microprocessors & Microcontrollers: Interrupt controller 8259; The 8259 is known as the Programmable Interrupt Controller (PIC) microprocessor. In 8085 and 8086 there are five hardware interrupts and two hardware interrupts respectively. Bu adding 8259, we can increase the interrupt handling capability. This chip combines the multi-interrupt input source to single interrupt output. This provides 8-interrupts from IR0 to IR7. Let us see some features of this microprocessor.
This chip is designed for 8085 and 8086.
It can be programmed either in edge triggered, or in level triggered mode
We can mask individual bits of Interrupt Request Register.
By cascading 8259 chips, we can increase interrupts up to 64 interrupt lines
Clock cycle is not needed.
8259 microprocessor can be programmed according to given interrupts condition and it can be provided either with level or edge-triggered interrupt level.
It can be programmed to either work in 8085 or in 8086 microprocessors.
Individual interrupt bits can be masked.
By cascading Nine 8259’s in Master-Slave Configuration we can handle up to 64 interrupt pins.
It contains 3 registers commonly known as ISR, IRR, IMR & there is 1 priority resolver (PR).
Interrupt Request Register (IRR): It stores those bits which are requested for their interrupt services.
Interrupt Service Register (ISR): It stores the interrupt levels which is currently being served.
Interrupt Mask Register (IMR): It stores interrupt levels that have to be masked. These interrupt levels are already accepted by the 8259 microprocessor.
Priority Resolver (PR): It examines all the 3 registers and sets the priority of interrupts and sets the interrupt levels in ISR which has the highest priority and the rest of the interrupt bit is IRR which is already accepted.
SP/EN (low active pin): If its value is 1 it works in master mode & if its value=e is 0 then it works in slave mode.
Cascade Buffer: It is used to cascade more number of Programmable Interrupt Controller to increase the interrupts handling capability up to 64 levels.
Advantages:
Interrupt management: The 8259 microprocessor is a specialized chip that is dedicated to managing interrupts, which can help to improve system performance and reduce the workload on the main CPU.
Programmability: The 8259 microprocessor is programmable, which means that it can be customized to handle specific types of interrupts and to prioritize different interrupt requests.
Compatibility: The 8259 microprocessor is compatible with a wide range of microprocessors, making it a popular choice for interrupt management in many different systems.
Multiple interrupt inputs: The 8259 microprocessor can handle multiple interrupt inputs, which makes it a useful peripheral for managing complex systems with multiple devices.
Ease of use: The 8259 microprocessor includes simple interface pins and registers, making it relatively easy to use and program.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
HEAP SORT ILLUSTRATED WITH HEAPIFY, BUILD HEAP FOR DYNAMIC ARRAYS.
Heap sort is a comparison-based sorting technique based on Binary Heap data structure. It is similar to the selection sort where we first find the minimum element and place the minimum element at the beginning. Repeat the same process for the remaining elements.
2. 8259 PIC
• The 8259A is a programmable interrupt controller(PIC) specially designed
to work with Intel microprocessor 8080, 8085A, 8086, 8088.
• It is a tool for managing the interrupt requests and functions as an overall
manager in an Interrupt-Driven system environment.
• It accepts requests from the peripheral equipment, determines which of
the incoming requests is of the highest priority, ascertains whether the
incoming request has a higher priority value than the level currently being
serviced, and issues an interrupt to the CPU based on this determination.
• The PIC, after issuing an Interrupt to the CPU, must somehow input
information into the CPU that can ``point'' the Program Counter to the
service routine associated with the requesting device.
3. 8259 PIC
• 8259 PIC can handle up to 8 vectored priorities interrupts for the
processor and it can be cascaded in master-slave configuration to
handle 64 levels of interrupts without any additional circuitry.
• It can be programmed either in level triggered or in edge triggered
interrupt level and also we can masked individual bits of interrupt
request register.
• It has Internal priority resolver which can be programmed into fixed
priority mode and rotating priority mode.
6. Data bus buffer:
• This, bidirectional 8-bit buffer is used to interface the 8259A to the
system data bus.
• Control words and status information from the microprocessor to PIC
and from PIC to microprocessor respectively, are transferred through
the data bus buffer.
• The processor sends control word to data bus buffer through D0-D7.
• The processor read status word from data bus buffer through D0-D7
• Also, after selection of Interrupt by 8259 microprocessor, it transfer
the opcode of the selected Interrupt and address of the Interrupt
service sub routine to the other connected microprocessor.
7. Read/Write & Control Logic
• The function of this block is to accept output commands sent from the
CPU.
• It contains the initialization command word (ICW) registers and operation
command word (OCW) registers which store the various control formats
for device operation.
• ICW and OCW are two types of command words of 8259, where ICW is
used to initialize 8259 where as OCW are issued to control the operation of
8259.
• This function block also allows the status of 8259A to be transferred to the
data bus.
• Control Logic
• The function of control logic is to control all the internal operations, generates an INT
signal to 8085 and receives INTA signal from 8085.
8. Pins Connected with Read/Write & Control
Logic
• RD, WR, CS and A0 are the control signals used in Read/Write
and Control Logic.
• The processor uses the RD (low), WR (low) and A0 to read or
write 8259.
• A LOW on WR input enables the CPU to write control words
(ICWs and OCWs) to the 8259A.
• A LOW on RD input enables the 8259A to send the status of
the Interrupt Request Register (IRR), In Service Register (ISR),
the Interrupt Mask Register (IMR), or the Interrupt level onto
the Data Bus.
• A0 input signal is used in conjunction with WR and RD signals
to write commands into the various command registers, as well
as reading the various status registers of the chip. This line can
be tied directly to one of the address lines
9. This Sub System of 8259 handles all the
external Interrupt requests
10. Interrupt Request Register (IRR):
• This block accepts and stores the actual interrupt
requests from external interrupting devices on IR0 –
IR7 lines.
• Interrupt request register (IRR) stores all the incoming
interrupt inputs that are requesting service.
• It is an 8-bit register – one bit for each interrupt
request.
• Basically, it keeps track of which interrupt inputs are
asking for service and also stores the pending
interrupt requests.
• If an interrupt input is unmasked, and has an
interrupt signal on it, then the corresponding bit in
the IRR will be set.
11. Interrupt Mask Register (IMR):
• This logic block masks interrupt lines based on
programming by the processo and prevents
masked interrupt lines from interrupting the
processor.
• The IMR is used to disable (Mask) or enable
(Unmask) individual interrupt request inputs.
• This is also an 8-bit register. Each bit in this
register corresponds to the interrupt input with
the same number.
• The IMR operates on the IRR. Masking of higher
priority input will not affect the interrupt request
lines of lower priority.
• To unmask any interrupt the corresponding bit is
set ‘0’
12. In-service Register (ISR):
• The in-service register keeps track of which interrupt
inputs are currently being serviced.
• For each input that is currently being serviced the
corresponding bit of in-service register (ISR) will be
set.
• In 8259A, during the service of an interrupt request,
if another higher priority interrupt becomes active, it
will be acknowledged and the control will be
transferred from lower priority interrupt service
subroutine (ISS) to higher priority ISS.
• Thus, more than one bit of ISR will be set indicating
the number of interrupts being serviced.
• Each of these 3-registers can be read as status
register.
13. Priority Resolver:
• This logic block determines the priorities of
the incoming interrupts set in the IRR.
• It takes the information from IRR, IMR and ISR
to determine whether the new interrupt
request is having highest priority or not.
• If the new interrupt request is having the
highest priority, it is selected and processed.
• The corresponding bit of ISR will be set during
interrupt acknowledge machine cycle
14. Cascade Buffer/Comparator:
• This logic allows for cascading multiple 8259 controllers
in a Master/ Slave configuration.
• This function block stores and compares the IDs of all
8259A’s in the system.
• The associated 3-I/O lines (CAS2-CAS0) are outputs
when 8259A is used as a master and are inputs when
8259A is used as a slave.
• As a master, the 8259A sends the ID of the interrupting
slave device onto the CAS2-0 lines.
• The slave 8259As compare this ID with their own
programmed ID.
• Thus selected 8259A will send its pre-programmed
subroutine address on to the data bus during the next
one or two successive INTA pulses.
15. How does the Master-Slave concept work?
• The slave 8259 creates an interrupt trigger on master as soon as it
receives an interrupt trigger at one of its eight input lines.
• The master in turn interrupts the processor.
• The processor read Interrupts Service Routine address.
• The master 8259 informs the corresponding slave 8259 to release the
ISR address onto the Data Bus.
• The processor reads this information and executes the appropriate
Interrupt service Routine.
16. INTERCONNECTING OF MASTER /SLAVE PICs
AND CPU
• Each PIC scheme provides to receive only up to 8 IR signals. If
required more than 8 IR signals then used multiple PIC schemes from
which one is master and others are slave. At this case PIC schemes are
used in cascading mode.
• In cascading mode INT outs of Slave are connected into nonuse IR line
of Master.
• INTR input of CPU can be receives common interrupt request signal
only from INT output of single Master.
• Number of selected interrupt vector can be transferred from only
Master PIC
17. PIN Diagram of 8259
1. D7- D0 is connected to microprocessor data bus D7-D0 (AD7-AD0).
2. IR7- IR0, Interrupt Request inputs are used to request an interrupt and to connect
to a slave in a system with multiple 8259As
3. WR - the write input connects to write strobe signal of microprocessor.
4. RD - the read input connects to the IORC signal
5. INT - the interrupt output connects to the INTR pin on the microprocessor from the
master, and is connected to a master IR pin on a slave.
6. INTA - the interrupt acknowledge is an input that connects to the INTA signal on the
system. In a system with a master and slaves, only the master INTA signal is
connected.
7. A0 - this address input selects different command words within the 8259A.
8. CS - chip select enables the 8259A for programming and control.
9. SP/EN - Slave Program/Enable Buffer is a dual-function pin.
• When the 8259A is in buffered mode, this pin is an output that controls the
data bus transceivers in a large microprocessor-based system.
• When the 8259A is not in buffered mode, this pin programs the device as a
master (1) or a slave (0).
10. CAS2-CAS0, the cascade lines are used as outputs from the master to the slaves for
cascading multiple 8259As in a system.
18. 8259A Interrupt Operation
• To implement interrupt, the interrupt enable flip-flop in the microprocessor
should be enabled by writing the EI instruction and the 8259A should be
initialized by writing control words in the control register. The 8259A requires two
types of control words:
a. Initialization Command Words (ICWS)
b. Operational Command Words (OCWs)
• ICWs are used to set up the proper conditions and specify RST vector address.
The OCWs are used to perform functions such as masking interrupts, setting up
status-read operations etc.
• Step-1: The IRR of 8259A stores the request.
• Step-2: The priority resolver checks 3 registers-
• The IRR for interrupt requests.
• IMR for masking bits and
• The ISR for interrupt request being served
• It resolves the priority and sets the INT high when appropriate.
19. 8259A Interrupt Operation
• Step-3: The MPU acknowledges the interrupt by sending signals in 𝐼𝑁𝑇A
• Step-4: After the 𝐼𝑁𝑇𝐴 is received, the appropriate bit in the ISR is set to indicate which interrupt
level is being served and the corresponding bit in the IRR is reset to indicate that the request for
the CALL instruction is placed on the data bus.
• Step-5: When MPU decodes the CALL instruction, it places two more 𝐼𝑁𝑇𝐴 signals on the data
bus.
• Step-6: When the 8259A receives the second 𝐼𝑁𝑇𝐴, it places the low-order byte of the CALL
address on the data bus. At the 3rd 𝐼𝑁𝑇𝐴, it places the high order byte on the data bus. The CALL
address is the vector memory location for the interrupt, this address is placed in the control
register during the initialization.
• Step-7: During the 3rd 𝐼𝑁𝑇𝐴 pulse, the ISR bit is reset either automatically (Automatic-End-of
Interrupt-AEOI) or by a command word that must be issued at the end of the service routine (End
of Interrupt-EOI).This option is determined by the initialization command word (ICW).
• Step-8: The program sequence is transferred to the memory location specified by the CALL
instruction