DiGiTronica

Principles of Computer Architecture and Maintenance

2011-05-24T16:12:00.011+05:30

PC Guide
North Bridge-South Bridge
Intel 915 Chipset
Intel 945 Chipset
Introduction to PC Hardware
PC Architecture Online book by Michael Karbo
Chapter 1 PPT: Different PC Configurations
Chapter1 PPT: CHIPSET
Chapter 1 PPT: Motherboard Buses
Chapter 1 PPT: Logical Memory Organization
Chapter 2 PPT: Hard Disk
Chapter 2 : Hard disk servo
Chapter 2 Hard disk servo Diagram
Chapter 2 PPT: CD/DVD
Chapter 3 PPT: LCD Monitor
Chapter 3 CRT Monitor

DiGiTronica Tutorial Links

2011-05-24T15:28:00.001+05:30

Online course on Embedded Systems
Good info on variety of latest Technologies
Tutorials by Mr William Green from Drexel University. Some of the topics covered are PCB design, SMD, GPS, Fuzzy Controller.
This site is your source for hundreds of practical articles, tips, papers and resources about developing embedded systems. http://www.ganssle.co
Serial Communication
Free info by Berkeley Design Technology, Inc. Info includes mainly DSP related information.
C Tutorials:This site provides the opportunity to learn basic control and embedded system concepts while taking advantage of the low cost and convenience of using a PC as a platform.
Free Ebook: First Steps with Embedded Systems
What a Microcontroller Bootloader Is and How It Works?
Maxim: Over 2000 application notes and technical articles written by engineers, for engineers.
MATLAB Tutorial Videos
Embedded C basic Tutorial: While programming microcontrollers in C most of the time we have to deal with registers. Most common tasks are setting and clearing bits in a register and check whether a bit is 0 or 1 in a given register. Mr.Avinash Gupta has nicely presented these concepts.
PIC Tutorials
SMT Components
Eagle Schematic Tutorial

8051 TUTORIALS

MSBTE:Embedded Systems(9168) CHAPTER 1

2010-12-02T23:03:00.002+05:30

CHAPTER 1
IO PORTS AND INTERRUPTS

1.1 8051 Parallel I/O Ports

1.2 Interrupt handling & programming :

1.2.1 Concept of synchronous & asynchronous interrupts,

1.2.2 ISR

1.2.3 Programming external hardware interrupt & Timer interrupt.

Introduction

We are living in the Embedded World. We are surrounded with many embedded products and our daily life largely depends on the proper functioning of these gadgets.
Television, Radio, CD player of your living room, Washing Machine or Microwave Oven in the kitchen, Card readers, Access Controllers, Palm devices of our work space enable us to do many of our tasks very effectively.
Apart from all these, many controllers embedded in the automobiles take care of many important operations.

What is this Embedded System?

The computer you use to compose your mails, or create a document or analyze the database is known as the standard desktop computer. These desktop computers are manufactured to serve many purposes and applications. You need to install the relevant software to get the required processing facility.
In contrast, embedded controllers carryout a specific work for which they are designed. Most of the time, engineers design these embedded controllers with a specific goal in mind. So these controllers cannot be used in any other place.
Theoretically, an embedded controller is a combination of a piece of microprocessor based hardware and the suitable software to undertake a specific task.
These days designers have many choices in microprocessors/microcontrollers. Especially, in 8 bit and 32 bit, the available variety really may overwhelm even an experienced designer. Selecting a right microprocessor may turn out as a most difficult first step and it is getting complicated as new devices continue to pop-up very often.
In the 8 bit segment, the most popular and used architecture is Intel's 8051. Market acceptance of this particular family has driven many semiconductor manufacturers to develop something new based on this particular architecture. Even after 25 years of existence, semiconductor manufacturers still come out with some kind of device using this 8051 core.

What is the difference between a Microprocessor and Microcontroller?

By microprocessor is meant the general purpose Microprocessors such as Intel's X86 family (8086, 80286, 80386, 80486, and the Pentium) or Motorola's 680X0 family (68000, 68010, 68020, 68030, 68040, etc).
These microprocessors contain no RAM, no ROM, and no I/O ports on the chip itself. For this reason, they are commonly referred to as general-purpose Microprocessors.
A system designer using a general-purpose microprocessor such as the Pentium or the 68040 must add RAM, ROM, I/O ports, and timers externally to make them functional. Although the addition of external RAM, ROM, and I/O ports makes these systems bulkier and much more expensive, they have the advantage of versatility such that the designer can decide on the amount of RAM, ROM and I/O ports needed to fit the task at hand.
This is not the case with Microcontrollers. A Microcontroller has a CPU (a microprocessor) in addition to a fixed amount of RAM, ROM, I/O ports, and a timer all on a single chip.
In other words, the processor, the RAM, ROM, I/O ports and the timer are all embedded together on one chip.
The fixed amount of on-chip ROM, RAM, and number of I/O ports in Microcontrollers makes them ideal for many applications in which cost and space are critical.
In many applications, for example a TV remote control, there is no need for the computing power of a 486 or even an 8086 microprocessor. These applications most often require some I/O operations to read signals and turn on and off certain bits.

Microcontrollers for Embedded Systems

· Microprocessors and Microcontrollers are widely used in embedded system products. An embedded system product uses a microprocessor (or Microcontroller) to do one task only.

· A printer is an example of embedded system since the processor inside it performs one task only; namely getting the data and printing it.

· A PC can be used for any number of applications such as word processor, print-server, bank teller terminal, Video game, network server, or Internet terminal. Software for a variety of applications can be loaded and run.

· The reason a pc can perform variety of tasks is that it has RAM memory and an operating system that loads the application software into RAM memory and lets the CPU run it.

· In an Embedded system, there is only one application software that is typically burned into ROM.

· An x86 PC contains or is connected to various embedded products such as keyboard, printer, modem, disk controller, sound card, CD-ROM drives, mouse, and so on. Each one of these peripherals has a Microcontroller inside it that performs only one task.

· For example, inside every mouse there is a Microcontroller to perform the task of finding the mouse position and sending it to the PC. Table 1-1 lists some embedded products.

Home Appliance	Office	Automobiles	Instrumentation
Intercom	Telephones	Engine control	Climate control
Washing Machines	Computers	Air bag	Keyless Entry
TV's	Fax Machine	ABS (Automatic Brake System)	Security systems
DVD/CD player	Laser Printer	Transmission control

8051 Parallel I/O Ports

There are four ports P0, P1, P2 and P3 each use 8 pins, making them 8-bit ports.
All the ports latches upon RESET are one, If intermittently zero is written on port then to use any of these ports as an input port, it must be programmed to one.

All four ports in the 80C51 are bidirectional. Each consists of a latch (Special Function Register P0 ,P1,P2 and P3), an output driver, and an input buffer.
All the port latches in the 80C51 have 1’s written to them by the reset function. If a 0 is subsequently written to a port latch, it can be re configured as an input by writing a 1 to it.

Port 0:

Port 0 occupies a total of 8 pins (pins 32-39) . It can be used for input or output.

Above figure shows a functional diagram of a typical bit latch and I/O buffer in port 1.

The bit latch (one bit in the port’s SFR) is represented as a Type D flip-flop, which will clock in a value from the internal bus in response to a “write to latch” signal from the CPU.
The Q output of the flip-flop is placed on the internal bus in response to a“read latch” signal from the CPU.
The level of the port pin itself is placed on the internal bus in response to a “read pin” signal from the CPU.
Some instructions that read a port activate the “read latch” signal, and others activate the “read latch” signal, and others activate the “read pin” signal.
Port 0 differs in not having internal pull-ups. The pull-up FET in the P0 output driver is used only when the Port is emitting 1’s during external memory accesses. Otherwise the pull-up FET is off which forms open drain collector.
To use the pins of port 0 as both input and output ports, each pin must be connected externally to a 10K ohm pull-up resistor as shown in figure below.
The output drivers of Ports 0 are switchable to an internal ADDR/DATA bus by an internal CONTROL signal for use in external memory accesses.
To be used as an input, the port bit latch must contain a 1, which turns off the output driver FET.

Dual role of port 0:

Port 0 is also designated as AD0-AD7, allowing it to be used for both address and data. When connecting an 8051/31 to an external memory, port 0 provides both address and data.
The 8051 multiplexes address and data through port 0 to save pins. ALE indicates if P0 has address or data. When ALE = 0, it provides data D0-D7, but when ALE =1 it has address and data with the help of a 74LS373 latch.

Port 1: Port 1 occupies a total of 8 pins (pins 1 through 8). It can be used as input or output.

The bit latch is represented as a Type D flip-flop, which will clock in a value from the internal bus in response to a “write to latch” signal from the CPU.
The Q output of the flip-flop is placed on the internal bus in response to a“read latch” signal from the CPU.
The level of the port pin itself is placed on the internal bus in response to a “read pin” signal from the CPU.
Some instructions that read a port activate the “read latch” signal, and others activate the “read latch” signal, and others activate the “read pin” signal.
In contrast to port 0, this port does not need any pull-up resistors since it already has pull-up resistors internally.

Port 2 : Port 2 occupies a total of 8 pins (pins 21- 28). It can be used as input or output.

The bit latch is represented as a Type D flip-flop, which will clock in a value from the internal bus in response to a “write to latch” signal from the CPU.
The Q output of the flip-flop is placed on the internal bus in response to a“read latch” signal from the CPU.
The level of the port pin itself is placed on the internal bus in response to a “read pin” signal from the CPU.
Some instructions that read a port activate the “read latch” signal, and others activate the “read latch” signal, and others activate the “read pin” signal.
This port does not need any pull-up resistors since it already has pull-up resistors internally.
The output drivers of Ports 0 are switchable to an internal ADDR bus by an internal CONTROL signal for use in external memory accesses.

Dual role of port 2:

· Port 2 must be used along with P0 to provide the 16-bit address for the external memory. As shown in pin configuration 8051, port 2 is also designed as A8-A15, indicating the dual function.

· Since an 8051 is capable of accessing 64K bytes of external memory, it needs 16 bits of the address. While P0 provides the lower 8 bits via A0-A7, it is the job of P2 to provide bits A8-A15 of the address.

· In other words, when 8031 is connected to external memory, P2 is used for the upper 8 bits of the 16 bit address, and it cannot be used for I/O.

· Ports 0 and 2 may not be used as general purpose I/O when being used as the ADDR/DATA BUS.

Port 3

Port 3 occupies a total of 8 pins, pins 10 through 17. It can be used as input or output. Port 3 has the additional function of providing important signals as shown in figure below.

The bit latch is represented as a Type D flip-flop, which will clock in a value from the internal bus in response to a “write to latch” signal from the CPU.
The Q output of the flip-flop is placed on the internal bus in response to a“read latch” signal from the CPU.
The level of the port pin itself is placed on the internal bus in response to a “read pin” signal from the CPU.
Some instructions that read a port activate the “read latch” signal, and others activate the “read latch” signal, and others activate the “read pin” signal.
This port does not need any pull-up resistors since it already has pull-up resistors internally.
If a P3 bit latch contains a 1, then the output level is controlled by the signal labelled “alternate output function.” The actual P3.X pin level is always available to the pin’s alternate input function.

Read-modify-write feature:

· The ports in the 8051 can be accessed by the read-modify-write technique. This feature saves many lines of code by combining in a single instruction all three actions of (1) reading the port, (2) modifying it, and (3) writing to the port.

Single bit addressability of ports:

· There are times that we need to access only 1 or 2 bits of the port instead of the entire 8 bits. A powerful feature of 8051 I/O ports is their capability to access individual bits of the port without altering the rest of the bits in that port.

Interrupt handling & programming

Interrupts

· An interrupt is usually defined as an event that alters the sequence of instructions executed by a processor. Such events correspond to electrical signals generated by hardware circuits both inside and outside the CPU chip.

Interrupts are often divided into synchronous and asynchronous interrupts:

· Synchronous interrupts are produced by the CPU control unit while executing instructions and are called synchronous because the control unit issues them only after terminating the execution of an instruction.

· Asynchronous interrupts are generated by other hardware devices at arbitrary times with respect to the CPU clock signals.

· Intel microprocessor manuals designate synchronous and asynchronous interrupts as exceptions and interrupts, respectively.

· Interrupts are issued by interval timers and I/O devices; for instance, the arrival of a keystroke from a user sets off an interrupt.

· Exceptions, on the other hand arrive after the execution of an instruction, and are caused either by programming errors or by anomalous conditions. Eg. Page fault or when the cpu try to devide a number by 0.

· A trap is a kind of exceptions, whose main purpose is for debugging

· A software interrupt (Programmed Exceptions) occur at the request of the programmer. They are used to implement system calls. Software interrupt is a considered to be an exception (because they are synchronous).

Interrupt Service Routine ( ISR)

Upon receiving an interrupt signal, the microcontroller interrupts whatever it is doing and serves the device.
The program which is associated with the interrupt is called the interrupt service routine (ISR) or interrupt handler.
For every interrupt, there must be an interrupt service routine (ISR), or interrupt handler.
When an interrupt is invoked, the microcontroller runs the interrupt service routine.
For every interrupt, there is a fixed location in memory that holds the address of its ISR .
The group of memory locations set aside to hold the addresses of ISRs is called interrupt vector table.

Upon activation of an interrupt, the microcontroller goes through the following steps:

1. It finishes the instruction it is executing and saves the address of the next instruction (PC) on the stack

2. It also saves the current status of all the interrupts internally (i.e: not on the stack).

3. It jumps to a fixed location in memory, called the interrupt vector table, that holds the address of the ISR.

4. The microcontroller gets the address of the ISR from the interrupt vector table and jumps to it. It starts to execute the interrupt service subroutine until it reaches the last instruction of the subroutine which is RETI (return from interrupt)

5. Upon executing the RETI instruction, the microcontroller returns to the place where it was interrupted. First, it gets the program counter (PC) address from the stack by popping the top two bytes of the stack into the PC.Then it starts to execute from that address.

8051 INTERRUPTS

There are five interrupt sources for the 8051. Since the main RESET input can also be considered as an interrupt, six interrupts can be listed as follows:

Interrupt Vector address

-----------------------------------------------------------------------------------

RESET 0000h

External interrupt 0 0003h

Timer/counter 0 000Bh

External interrupt 1 0013h

Timer/counter 1 001Bh

Serial port 0023h

Enabling and disabling an interrupt

Upon reset, all interrupts are disabled (masked), meaning that none will be responded to by the microcontroller if they are activated.
The interrupts must be enabled by software in order for the microcontroller to respond to them.
There is a register called IE (interrupt enable) this is responsible for enabling (unmasking) and disabling (masking) the interrupts. The Interrupt Enable, IE, register is an SFR register at location A8h in Internal RAM.

Above figure shows the IE register. Note that IE is a bit-addressable register. From Figure notice that bit D7 in the IE register is called EA (enable all).
This must be set to 1 in order for the rest of the register to take effect. D6 is unused. D5 is used by the 8052 for Timer 2 interrupt. The D4 bit is for the serial interrupt, and so on.

Steps in enabling an interrupt

To enable an interrupt, we take the following steps:

Bit D7 of the IE register (EA) must be set to high to allow the rest of register to take effect.
If EA = 1, interrupts are enabled and will be responded to if their corresponding bits in IE are high. If EA = 0, no interrupt will be responded to, even if the associated bit in the IE register is high.

Programming External Hardware Interrupts

· We will concentrate on the external interrupts for now, and later we will examine the other interrupt sources.

· The 8051 has two external hardware interrupts PIN 12 (P3.2) and Pin 13 (P3.3) of the 8051, designated as INT0 and INT1 are used as external hardware interrupts.

· Here’s a brief look at some of the register bits which will be used to set up the interrupts. The EA bit will enable all interrupts (when set to 1) and the individual interrupts must also be enabled.

For example, if we want to enable the two external interrupts we would use the instruction:

MOV IE, #10000101B

Each of the two external interrupt sources can be defined to trigger on the external signal, either on a negative going edge or on a logic low level state. i.e. it can be either

Edge triggered
Level triggered.

Edge Triggered Interrupt:

Upon reset 8051 makes INT0 and INT1 low l Level-Triggered Interrupt. To make them Edge -Triggered Interrupt, we must program the IT0 and IT1 bits of the TCON Register.
In negative edge trigger mode, the interrupt in-service flag IE0 and IE1 of TCON registers are set while the interrupts are being serviced and automatically cleared by hardware once interrupts are processed.
The TCON register is another SFR register and is located at location 88h in Internal RAM. (The other bits in the TCON register will be described later in the context of the hardware Timer/Counters.)

The TCON register holds, among other bits, the IT0 and IT1 flag bits that determine level- or edge-triggered mode of the hardware interrupt
IT0 and IT1 are bits D0 and D2 of the TCON register They are also referred to as TCON.0 and TCON.2 since the TCON register is bit addressable
To define negative edge triggering for the two external interrupts use instructions as follows:

SETB TCON.0 ; negative edge trigger for interrupt 0

SETB TCON.2 ; negative edge trigger for interrupt 1

In edge-triggered interrupts the external source must be held high for at least one machine cycle, and then held low for at least one machine cycle
The falling edge of pins INT0 and INT1 are latched by the 8051 and is held by the TCON register bits D1 and D3 respectively. ( IE0 and IE1)
TCON.1 and TCON.3 bits of TCON register function as interrupt-in-service flags. High status on these flags indicates that the interrupt is being serviced now and on this INTn pin, and no new interrupt will be responded to until this service is finished.
These flags are cleared by the CPU once the ISRs are processed. There is no need for instruction CLR TCON.1 before RETI in the ISR associated with INT0 or INT1.

Level Triggered Interrupt:

In the level-triggered mode, INT0 and INT1 pins are normally high. If a low-level signal is applied to them, it triggers the interrupt then the microcontroller stops whatever it is doing and jumps to the interrupt vector table to service that interrupt.
The low-level signal at the INT pin must be removed before the execution of the last instruction of the ISR, RETI; otherwise, another interrupt will be generated.
This is the default mode upon reset of the 8051.

Programming Timer Interrupts

Roll-over timer flag and interrupt

The timer flag (TF) is raised when the timer rolls over.
In polling TF, we have to wait until the TF is raised. The problem with this method is that the microcontroller is tied down while waiting for TF to be raised, and cannot do any thing else.
Using interrupts solves this problem and avoids tying down the controller.
If the timer interrupt in the IE register is enabled, whenever the timer rolls over, TF is raised, and the microcontroller is interrupted in whatever it is doing, and jumps to the interrupt vector table to service the ISR. In this way, the microcontroller can do other things until it is notified.
Steps in programming Timer Interrupt

1. Bit D7 of the IE register (EA) must be set to high.

2. Enable bit D1(ET0) and D3(ET1) of IE register to enable Timer0 and Timer1 interrupt respectively.

3. Enter Timer0 and Timer1 ISR address in Interrupt vector table locations 000Bh and 001Bh respectively.

Interrupt priority level structure

· An individual interrupt source can be assigned one of two priority levels. The Interrupt Priority, IP, register is an SFR register used to program the priority level for each interrupt source.

· A logic 1 specifies the high priority level while a logic 0 specifies the low priority level.

An ISR routine for a high priority interrupt cannot be interrupted. An ISR routine for a low priority interrupt can be interrupted by a high priority interrupt, but not by a low priority interrupt.
If two interrupt requests, at different priority levels, arrive at the same time then the high priority interrupt is serviced first.
If two, or more, interrupt requests at the same priority level arrive at the same time then the interrupt to be serviced is selected based on the order shown below.
Note, this order is used only to resolve simultaneous requests. Once an interrupt service begins it cannot be interrupted by another interrupt at the same priority level.

Improve your Interview Skill

2010-12-01T01:25:00.001+05:30

Sit Down and Panic. The Interview is Yours @GayleHoward
How to Stand Out in a Job Interview @heathermundell
Avoid These Reference Mistakes @DawnBugni
Unspoken Secrets of Job Interviewing Prep: How Your Nonverbal Presentation and Behaviors Impact the Impression You Make @KatCareerGal
Prep for Interviews Now: Snuff out the Elephant in the Room Later! @chandlee << not working yet
What Should Job Seekers Do Now to Prepare for an Interview @erinkennedycprw
Take a Ride in the Elevator Before You Interview @barbarasafani
Are You Ready for the Elephant in the Room? @WorkWithIllness
"Tell Me About Yourself" (Oh, Yikes!), @KCCareerCoach
The job interview as a shared narrative @WalterAkana
Prepare your references for job search success @Keppie_Careers
No Pain No Gain In Job Search and Interview Prep @ValueIntoWords
Job searching? Take a cue from the Boy Scouts @LaurieBerenson
Preparing for Career Success Starts with Interviewing the Employers @JobHuntOrg

MSBTE Question Papers - First Year (E Scheme)

2010-11-30T00:14:00.003+05:30

Advanced Industrial Electronics

2010-08-17T23:37:00.006+05:30

CNC Tutorial

Direct Numeric Control

Alarm Annunciator

MSBTE Question Papers - Third Year (C Scheme)

2010-08-17T23:25:00.013+05:30

CISC Vs RISC

2010-08-12T00:33:00.004+05:30

Please click on the image to enlarge

Do visit this page for clear understanding of RISC-CISC concept in a simple way.

2010-08-10T22:10:00.001+05:30

Basic Tutorial for Keil Software

RESUME WRITING TIPS FOR ENGINEERING STUDENTS APPEARING FOR CAMPUS PLACEMENT

2010-08-01T22:23:00.003+05:30

Dear Students,

You are in the final year now and must be very excited about the campus placements. Final year students and fresh graduates often face the challenge of writing resumes that can effectively market them to recruiters. In such resume, one needs to shift the emphasis on academic achievements rather than professional achievements owing to the general lack of work experience.

Remember…..

Even if you don’t have professional experience, your credentials are still worth noting down.

You can use your resume to show employers the value you'll bring to their organization.

The employer requires an account of skills that showcase one’s potential despite the lack of adequate work experience.

Follow the guideline given below while drafting Resume for campus placements:

Resume should be well drafted in a short and concise format. An effective resume should constitute an education background and qualifications that are relevant to the job that is being sought. The language should be simple without use of unnecessary complex words.

The resume should begin with your name and clear contact details.

Use a summary of qualifications, rather than writing “objective” in the beginning. It's a great way to emphasize your academic record, skills in ways that will be meaningful to the employer. Highlight your academic record (if it is good), and your personality traits that best match with those required for the job.

Do mention the important courses you took during engineering. Resume should reveal the skills you gained such as computer programming, technical writing, and project management skills.

If you have earned any scholarships, awards then make note of them. Educational qualifications should be chronologically indicated along with the institutions that were attended.

Include any internship or part-time jobs. Highlight any skills or achievements gained during that employment. Projects and extra curricular activities should be mentioned to show how the individual will contribute to the organization.

Mention specific courses or training programs which you might have attended and which might give you a good edge over those who have only the required qualifications and work experience.

Highlight the skills which you might have acquired through self learning. Be careful that you write only what you really know well. You can expect questions based on the skills you mentioned in the Resume.

Don't be tempted to impress an employer by adding false details.

Even though you are applying for your first job, follow a professional resume format, take time with your wording, and leave no spelling mistakes unattended!

Overall be sure that you project a positive attitude and a willingness to jump and get things done.

VAN-NEUMANN ARCHITECTURE Vs HARVARD ARCHITECTURE

2010-07-20T01:40:00.003+05:30

VAN-NEUMANN ARCHITECTURE	HARVARD ARCHITECTURE
Used in conventional processors found in PCs and Servers, and embedded systems with only control functions.	Used in DSPs and other processors found in latest embedded systems and Mobile communication systems, audio, speech, image processing systems
The data and program are stored in the same memory	The data and program memories are separate
The code is executed serially and takes more clock cycles	The code is executed in parallel
There is no exclusive Multiplier	It has MAC (Multiply Accumulate)
Absence of Barrel Shifter	Barrel Shifter help in shifting and rotating operations of the data
The programs can be optimized in lesser size	The program tend to grow big in size

Technical Writing for Engineering Students

2010-03-08T01:52:00.001+05:30

MSBTE has included some excellent subjects like Development of Life Skills, Professional Practices etc in the diploma curriculum that is implemented in all the polytechnics in Maharashtra. These subjects, no doubt if implemented properly will benefit the engineering students immensely.

Polytechnics under MSBTE are located in urban as well as rural places in Maharashtra. MSBTE has given a lot of attention while designing syllabus so that the balance can be maintained between rural Maharashtra and urban Maharashtra. I teach in one of the best Polytechnics in Mumbai .While conducting practical sessions of subject " Professional Practices" I realize the need of emphasizing on developing Technical writing skills for the students. Preparing technical presentations, writing various technical reports such as design reports, progress reports, theses and dissertation are integral tasks in any Engineer's Life!

These skills can also be developed by the students and taught by Lecturers while learning core subjects but most of the times these things take back seat when it come to completing syllabus. We all are aware how a typical engineering student completes his "submission" at the last moment just before the deadline!

My this post is to help students to learn Technical writing. I will post links and articles here. I usually post links under different post headings. For example "Tutorial Links", "Design Links" or post related to links on mixed topics is labeled as "Potpourri" . But this time I thought of writing separate post for links related to Technical writing because I don't want to go this link unnoticed!

Cheers!

LINKS

These guidelines for engineering writing and scientific writing are designed to help students communicate their technical work. To that end, these guidelines contain advice, models, and exercises for common writing and speaking assignments in engineering and science.

Comparison between CAN and FIREWIRE

2010-02-21T01:24:00.003+05:30

The CAN bus offers a high-speed communication rate up to 1 M bits / sec, for up to 40 feet, thus facilitating real-time control. The original IEEE 1394 specifications allowed for speeds of 100, 200, and 400Mbps, IEEE 1394b provides speeds of 800, 1600, and 3200Mbps.

CAN protocol can link up to 2032 devices (assuming one node with one identifier) on a single network. But accounting to the practical limitations of the hardware (transceivers), it may only link up to 110 nodes on a single network.FIREWIRE allows for the connection of up to 63 external devices.

In CAN it is possible to add nodes to the bus without reprogramming the other nodes to recognize the addition or changing the existing hardware i.e. “Hot-plugging” is possible.FIREWIRE supports “Hot swapping” that is the ability to add and remove devices to a computer while the computer is running and have the operating system automatically recognize the change.

CAN have gained widespread popularity for embedded control in the areas like industrial automation, automotives, mobile machines, medical, military and other harsh environment network applications.IEEE 1394 a very high-speed bus design that is ideal for high-bandwidth applications like multimedia..

DiGiTronica TechnoTools

2010-02-21T00:56:00.000+05:30

Calculator User Manual: Have you lost the user manual that comes with the Casio Calculator? Use this Link to download the same. This manual is for calculators of series FX- 82MS to FX 350MS

GSM MODEM

2010-02-05T23:59:00.001+05:30

1.SMS Client - Server Software is used for sending, reading, deleting messages. It uses GSM modem for sending SMS. It listens for incoming messages to arrive, processes the read message and takes action accordingly. This SMS software requires GSMComm Library which you can also download.

2.This is a website about working with GSM SMS messages. It's more software developer oriented, but also users may find useful things here.

Embedded SoftwareDevelopment Process

2010-01-28T00:38:00.006+05:30

This article provides a generic description of the end-to-end process from C source file development to downloading machine code in the target processor. Details for a specific software suite coupled with a specific target controller may have slight differences.

As the system designer, you will write the C source files that implement the required control algorithm. The source files consist of C source code and also header files. Header files may include functions you have written, functions provided with your compiler, and also personality data for the specific processor you are using as the target system.

The C source files are compiled using a compiler for the specific target processor. The output from the compiler will be assembly code which is automatically routed to the assembler portion of the software development suite. The output from the assembler is object code which is linked with library files provided with the compiler.

The overall output will be machine code for download into the target processor. The software development suite may also provide some auxiliary files. These files provide information on memory usage and code placement within memory. These files are handy if system troubleshooting is required.

The machine code is downloaded into the target controller via a programming cable.

DiGiTronica "Jara Hatke"!

2009-03-03T00:53:00.005+05:30

The Intel Museum!
The Intel Museum's online exhibits are a great way to complement your visit or to explore the museum if you can't make a trip to the physical museum in Santa Clara, California, USA.

FileFactory
FileFactory lets you host files up to 300MB for free. You don't have to register.Your files can be downloaded an unlimited number of times!

Flipkart
Online Bookstore from India!

One Smart Click!

Electronics Engineering Herald
An online magazine for electronic engineers with focus on hardware design, embedded, VLSI, and design tools. EE Herald publishes design ideas, technology trends, course materials, electronic industry related news and new products.

MSBTE Embedded Systems (9168)

2009-01-19T17:13:00.010+05:30

8051 I/O port status upon Reset
Embedded Systems Syllabus
MSBTE Sample Papers 6th Semester
Can you access individual 8051 registers (R0 to R7) in Keil C?
Excellent 8051 simulator that is available for FREE.The best part of this simulator is that it has several peripheral simulation included.
Source code for Timer Tick library. Application notes on how interrupt driven generic timer delay routine can be written and used.
CAN Tutorial
RTOS Webinar
PCI PPT, PCI Configuration Header

DiGiTronica Potpourri

2008-12-30T01:21:00.005+05:30

8052.com is a website provided free-of-charge to the 8052/MCS-51 community. The vast majority of the prepared material on 8052.com is written by the webmaster Craig Steiner who is a founding member of Vault Information Services LLC. The site receives approximately half a million "hits" from human beings (as opposed to web spiders) every month and is the primary community for developers and engineers interested in MCS-51 architecture.

http://www.microcontroller.com/

http://electrofriends.com/

Embedded Craft is the information portal useful for those who are working in embedded systems domain or want to start new career in this field.

www.ikalogic.com By Joining ikalogic community, you can download project folders, free software, and video clips, share questions and ideas and receive mail notifications when new interesting content is uploaded.

http://embeddedcookbook.com Share, Collaborate and Learn! A website for electronic developers to improve the documentation of electronic parts and to avoid reinventing the wheel each time we need to use a new component.

Electronic open source : This is for the technocrat who believes that sharing one self experience, in terms of code, schematics, bug report etc. is as much important as taking benefit from other people experience.

Cornell University: Designing with Microcontrollers course

Stanford University's Embedded System Design Laboratory

Santa Clara University: Embedded System Resources

Rickey's World of Microcontrollers:Here you will find everything related to microcontrollers, you can download codes, libraries, examples, discuss about your projects and ask doubts in the forum.

Microcontrollershop.com site has list of books on various engineering topics, such as microcontroller architectures, embedded system design and firmware software development.Books have been grouped into sub-categories by topic. Books specific to a microcontroller architecture are grouped by manufacturer/architecture.

This blog is maintained by the Princeton University Library. Started in 2006, it gives students and visitors relevant information on engineering. The numerous categories include awards, tips, documents, news, projects, and more.
EE Times Education and Training

DiGiTronica Design Links

2008-12-30T00:15:00.001+05:30

Learn designing with electronidesign.com on various topics like Embedded, Automation, Communication,Power, Analog/Mixed signals etc.

DiGiTronica Technobuyer's Links

2008-12-27T00:30:00.002+05:30

http://robokits.co.in/shop/

Import from China to Chandani Chowk! http://www.seeedstudio.com/depot/

http://www.sunrom.com/

GSM/GPRS Modem at reasonable cost in Mumbai

http://www.shreeramindia.com/index.html

http://www.kitsnspares.com/user1/buyproduct.asp

DiGiTronica Project Links

2008-10-26T14:56:00.002+05:30

http://www.electronics-lab.comHere you can find useful circuits with full description, diagrams and PCB, electronics articles, links and downloads.

http://www.circuitgeek.comWelcome to CircuitGeek. This is a place where you can find useful circuits, interesting projects, and electronics related articles. Site is updated frequently with electronics projects, events found in the internet.

http://www.circuit-projects.comYou can find as well as share your own electronic circuit schematics/diagrams or projects with people from all around the world.

http://www.projects-lab.com

http://www.scienceprog.com

GPS Tracking

http://www.youritronics.com

http://www.uchobby.com

http://www.e-dsp.com

http://www.diylive.net Do-it-yourself projects and technology updates

http://www.embedds.com

Digital BugsThe Digital Bugs (also known as DiBugs) is a place where you can find lots of friends facing similar computer, windows, or other technology and evnen non technology related problems. Here we can learn new stuff together, solve small problems related to Windows XP, Vista, particular programs and much more.

http://www.elecfree.comhttp://microblog.routed.netp

http://www.arduino.cc Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It's intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments.

Ladyada: Most of the stuff on this site is related to the electronic toys, gadgets and art that Limor, an engineer currently working with Adafruit Industries worked on since 2003.

FPGA based simple projects. You can find information pages, as well as FPGA projects to build with an FPGA board.

प्रत्यूष

2008-01-28T01:40:00.000+05:30

प्रत्यूष