The document discusses interrupts for the 8085 microprocessor. There are two types of interrupts - maskable and non-maskable. Maskable interrupts can be delayed or rejected using EI and DI instructions, while non-maskable interrupts cannot be delayed or rejected. Interrupts can also be classified as vectored or non-vectored depending on whether the address of the service routine is hardcoded or needs to be supplied externally. The 8085 has specific interrupt inputs including INTR, RST 5.5, RST 6.5, RST 7.5, and TRAP. These interrupts differ in terms of whether they are maskable or vectored. Instructions like SIM and RIM can be used to manipulate
This method of checking the signal in the system for processing is called Polling Method. In this method, the problem is that the processor has to waste number of clock cycles just for checking the signal in the system, by this processor will become busy unnecessarily. If any signal came for the process, processor will take some time to process the signal due to the polling process in action. So system performance also will be degraded and response time of the system will also decrease.
This method of checking the signal in the system for processing is called Polling Method. In this method, the problem is that the processor has to waste number of clock cycles just for checking the signal in the system, by this processor will become busy unnecessarily. If any signal came for the process, processor will take some time to process the signal due to the polling process in action. So system performance also will be degraded and response time of the system will also decrease.
Interrupts is a signal from a device attached to a computer or from a program within the computer which causes the main program that operates the computer to stop and figure out what to do next.
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.
Water billing management system project report.pdfKamal Acharya
Our project entitled “Water Billing Management System” aims is to generate Water bill with all the charges and penalty. Manual system that is employed is extremely laborious and quite inadequate. It only makes the process more difficult and hard.
The aim of our project is to develop a system that is meant to partially computerize the work performed in the Water Board like generating monthly Water bill, record of consuming unit of water, store record of the customer and previous unpaid record.
We used HTML/PHP as front end and MYSQL as back end for developing our project. HTML is primarily a visual design environment. We can create a android application by designing the form and that make up the user interface. Adding android application code to the form and the objects such as buttons and text boxes on them and adding any required support code in additional modular.
MySQL is free open source database that facilitates the effective management of the databases by connecting them to the software. It is a stable ,reliable and the powerful solution with the advanced features and advantages which are as follows: Data Security.MySQL is free open source database that facilitates the effective management of the databases by connecting them to the software.
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.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
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Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
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.
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.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
2. Interrupts
Interrupt is a process where an external
device can get the attention of the
microprocessor.
◦ The process starts from the I/O device
◦ The process is asynchronous.
TYPES OF INTERRUPT:
SOFTWARE
AND HARDWARE
VECTORED AND MASKABLE AND
NON VECTORED NON MASKABLE
3. Classification of Interrupts
Interrupts can be classified into two types:
Maskable Interrupts (Can be delayed or Rejected)
Enable Or Disable By EI And DI Instruction
Non-Maskable Interrupts (Can not be delayed or
Rejected)
Interrupts can also be classified into:
Vectored (the address of the service routine is hard-wired)
Non-vectored (the address of the service routine needs to be
supplied externally by the device)
4. Interrupts
An interrupt is considered to be an emergency
signal that may be serviced.
The Microprocessor may respond to it as soon as
possible.
What happens when MP is interrupted ?
When the Microprocessor receives an interrupt signal,
it suspends the currently executing program and
jumps to an Interrupt Service Routine (ISR) to
respond to the incoming interrupt.
Each interrupt will most probably have its own ISR.
5. Responding to Interrupts
Responding to an interrupt may be immediate or
delayed depending on whether the interrupt is
maskable or non-maskable and whether
interrupts are being masked or not.
There are two ways of redirecting the execution
to the ISR depending on whether the interrupt is
vectored or non-vectored.
◦ Vectored: The address of the subroutine is already
known to the Microprocessor
◦ Non Vectored: The device will have to supply the
address of the subroutine to the Microprocessor
6. The 8085 Interrupts
Interrupt name Maskable Vectored
VECTOR
ADDRESS
TRAP No Yes 0024H
RST 7.5 Yes Yes 003CH
RST 6.5 Yes Yes 0034H
RST 5.5 Yes Yes 002CH
INTR Yes No --
7. The 8085 Interrupts
When a device interrupts, it actually wants the
MP to give a service which is equivalent to
asking the MP to call a subroutine. This
subroutine is called ISR (Interrupt Service
Routine)
The ‘EI’ instruction is a one byte instruction and
is used to Enable the non-maskable interrupts.
The ‘DI’ instruction is a one byte instruction and
is used to Disable the non-maskable interrupts.
The 8085 has a single Non-Maskable interrupt.
The non-maskable interrupt is not affected by the
value of the Interrupt Enable flip flop.
8. The 8085 Interrupts
The 8085 has 5 interrupt inputs.
The INTR input.
The INTR input is the only non-vectored interrupt.
INTR is maskable using the EI/DI instruction pair.
RST 5.5, RST 6.5, RST 7.5 are all automatically
vectored.
RST 5.5, RST 6.5, and RST 7.5 are all maskable.
TRAP is the only non-maskable interrupt in the
8085
TRAP is also automatically vectored
10. Interrupt Vectors and the Vector
Table
An interrupt vector is a pointer to where the
ISR is stored in memory.
All interrupts (vectored or otherwise) are
mapped onto a memory area called the
Interrupt Vector Table (IVT).
The IVT is usually located in memory page 00
(0000H - 00FFH).
The purpose of the IVT is to hold the vectors that
redirect the microprocessor to the right place
when an interrupt arrives.
11. The 8085 Non-Vectored Interrupt
Process
1. The interrupt process should be enabled using the EI
instruction.
2. The 8085 checks for an interrupt during the execution of every
instruction.
3. If INTR is high, MP completes current instruction, disables the
interrupt and sends INTA (Interrupt acknowledge) signal to the
device that interrupted
4. INTA allows the I/O device to send a RST instruction through
data bus.
5. Upon receiving the INTA signal, MP saves the memory location of the
next instruction on the stack and the program is transferred to ‘call’
location (ISR Call) specified by the RST instruction
12. The 8085 Non-Vectored Interrupt
Process
6. Microprocessor Performs the ISR.
7. ISR must include the ‘EI’ instruction to enable the
further interrupt within the program.
8. RET instruction at the end of the ISR allows the MP
to retrieve the return address from the stack and the
program is transferred back to where the program
was interrupted.
13. The 8085 Maskable/Vectored
Interrupts
The 8085 has 4 Masked/Vectored interrupt inputs.
RST 5.5, RST 6.5, RST 7.5
They are all maskable.
They are automatically vectored according to the following
table:
The vectors for these interrupt fall in between the vectors for
the RST instructions. That’s why they have names like RST
5.5 (RST 5 and a half).
Interrupt Vector
RST 5.5 002CH
RST 6.5 0034H
RST 7.5 003CH
14. Masking RST 5.5, RST 6.5 and RST 7.5
These three interrupts are masked at two
levels:
Through the Interrupt Enable flip flop and the
EI/DI instructions.
The Interrupt Enable flip flop controls the whole
maskable interrupt process.
Through individual mask flip flops that control the
availability of the individual interrupts.
These flip flops control the interrupts individually.
15. Maskable Interrupts and vectorlocations
Interrupt
Enable
Flip Flop
INTR
RST 5.5
RST 6.5
RST 7.5
M 5.5
M 6.5
M 7.5
RST7.5 Memory
** See Fig 12.5 of the
Text Book for a
detailed look
16. The 8085 Maskable/Vectored Interrupt Process
1. The interrupt process should be enabled using the EI
instruction.
2. The 8085 checks for an interrupt during the
execution of every instruction.
3. If there is an interrupt, and if the interrupt is enabled
using the interrupt mask, the microprocessor will
complete the executing instruction, and reset the
interrupt flip flop.
4. The microprocessor then executes a call instruction
that sends the execution to the appropriate location
in the interrupt vector table.
17. The 8085 Maskable/Vectored Interrupt Process
5. When the microprocessor executes the call
instruction, it saves the address of the next
instruction on the stack.
6. The microprocessor jumps to the specific service
routine.
7. The service routine must include the instruction EI to
re-enable the interrupt process.
8. At the end of the service routine, the RET instruction
returns the execution to where the program was
interrupted.
18. Manipulating the Masks
The Interrupt Enable flip flop is manipulated
using the EI/DI instructions.
The individual masks for RST 5.5, RST 6.5
and RST 7.5 are manipulated using the SIM
instruction.
This instruction takes the bit pattern in the
Accumulator and applies it to the interrupt mask
enabling and disabling the specific interrupts.
19. How SIMInterprets the Accumulator
SDO
SDE
XXX
R7.5
MSE
M7.5
M6.5
M5.5
01234567
RST5.5 Mask
RST6.5 Mask
RST7.5
Mask
}0 - Available
1 - Masked
Mask Set Enable
0 - Ignore bits 0-2
1 - Set the masks according
to bits 0-2
Force RST7.5 Flip Flop to resetNot Used
Enable Serial Data
0 - Ignore bit 7
1 - Send bit 7 to SOD pin
Serial Data Out
20. SIMand the Interrupt Mask
Bit 0 is the mask for RST 5.5
Bit 1 is the mask for RST 6.5
Bit 2 is the mask for RST 7.5.
If the mask bit is 0, the interrupt is available.
If the mask bit is 1, the interrupt is masked.
21. Bit 3 (Mask Set Enable - MSE) is an enable for
setting the mask.
If it is set to 0 the mask is ignored and the
old settings remain.
If it is set to 1, the new setting are applied.
The SIM instruction is used for multiple
purposes and not only for setting interrupt
masks.
It is also used to control functionality such as
Serial Data Transmission.
Therefore, bit 3 is necessary to tell the
microprocessor whether or not the interrupt
masks should be modified
22. SIMand the Interrupt Mask
The RST 7.5 interrupt is the only 8085 interrupt that has
memory.
If a signal on RST7.5 arrives while it is masked, a flip flop will
remember the signal.
When RST7.5 is unmasked, the microprocessor will be
interrupted even if the device has removed the interrupt signal.
This flip flop will be automatically reset when the microprocessor
responds to an RST 7.5 interrupt.
Bit 4 of the accumulator in the SIM instruction allows explicitly
resetting the RST 7.5 memory even if the microprocessor did
not respond to it.
Bit 5 is not used by the SIM instruction
23. Using the SIM Instruction to Modify the Interrupt Masks
Example: Set the interrupt masks so that
RST5.5 is enabled, RST6.5 is masked, and
RST7.5 is enabled.
First, determine the contents of the accumulator
SDO
SDE
XXX
R7.5
MSE
M7.5
M6.5
M5.5
- Enable 5.5 bit 0 = 0
- Disable 6.5 bit 1 = 1
- Enable 7.5 bit 2 = 0
- Allow setting the masks bit 3 = 1
- Don’t reset the flip flop bit 4 = 0
- Bit 5 is not used bit 5 = 0
- Don’t use serial data bit 6 = 0
- Serial data is ignored bit 7 = 0
0 1 00000 1
Contents of accumulator are: 0AH
EI ; Enable interrupts including INTR
MVI A, 0A ; Prepare the mask to enable RST 7.5, and 5.5, disable 6.5
SIM ; Apply the settings RST masks
24. Triggering Levels
RST 7.5 is positive edge sensitive.
When a positive edge appears on the RST7.5 line, a logic 1
is stored in the flip-flop as a “pending” interrupt.
Since the value has been stored in the flip flop, the line
does not have to be high when the microprocessor checks
for the interrupt to be recognized.
The line must go to zero and back to one before a new
interrupt is recognized.
RST 6.5 and RST 5.5 are level sensitive.
The interrupting signal must remain present until the
microprocessor checks for interrupts.
25. Determining the Current Mask
Settings
RIM instruction: Read Interrupt Mask
Load the accumulator with an 8-bit pattern
showing the status of each interrupt pin and
mask.
27. The RIMInstruction and the
Masks
Bits 0-2 show the current setting of the mask for
each of RST 7.5, RST 6.5 and RST 5.5
They return the contents of the three mask flip flops.
They can be used by a program to read the mask settings
in order to modify only the right mask.
Bit 3 shows whether the maskable interrupt
process is enabled or not.
It returns the contents of the Interrupt Enable Flip Flop.
It can be used by a program to determine whether or not
interrupts are enabled.
28. The RIMInstruction and the
Masks
Bits 4-6 show whether or not there are
pending interrupts on RST 7.5, RST 6.5, and
RST 5.5
Bits 4 and 5 return the current value of the RST5.5
and RST6.5 pins.
Bit 6 returns the current value of the RST7.5 memory
flip flop.
Bit 7 is used for Serial Data Input.
The RIM instruction reads the value of the SID pin on
the microprocessor and returns it in this bit.
29. Pending Interrupts
Since the 8085 has five interrupt lines,
interrupts may occur during an ISR and
remain pending.
Using the RIM instruction, it is possible to can
read the status of the interrupt lines and find if
there are any pending interrupts.
See the example of the class
30. TRAP
TRAP is the only non-maskable interrupt.
It does not need to be enabled because it cannot be
disabled.
It has the highest priority amongst interrupts.
It is edge and level sensitive.
It needs to be high and stay high to be recognized.
Once it is recognized, it won’t be recognized again
until it goes low, then high again.
TRAP is usually used for power failure and
emergency shutoff.
31. Issues in Implementing INTR
Interrupts
How long must INTR remain high?
The microprocessor checks the INTR line one clock cycle before
the last T-state of each instruction.
The INTR must remain active long enough to allow for the
longest instruction.
The longest instruction for the 8085 is the conditional CALL
instruction which requires 18 T-states.
Therefore, the INTR must remain active for 17.5 T-states.
If f= 3MHZ then T=1/f and so, INTR must remain active for
[ (1/3MHZ) * 17.5 ≈ 5.8 micro seconds].
32. Issues in Implementing INTR
Interrupts
How long can the INTR remain high?
The INTR line must be deactivated before the EI
is executed. Otherwise, the microprocessor will
be interrupted again.
Once the microprocessor starts to respond to an
INTR interrupt, INTA becomes active (=0).
Therefore, INTR should be turned off as soon as
the INTA signal is received.