Friday, 12 February 2016

ለልጅዎ መጽሐፍ ቅዱሳዊ ስም ማውጣት ይፈልጋሉ?....ከዚህ ይመረጡ

1. ሆሴዕ - እግዚአብሔር ያድናል
2. ሐና - ጸጋ
3. ሔዋን - የሕያዋን ሁሉ እናት
4. ሕዝቅኤል - እግዚአብሔር ብርታትን ይሰጣል
5. ሕዝቅያስ - እግዚአብሔር ኃይል ነው
6. መልከ ጼዴቅ - የጽድቅ ንጉሥ
7. ሚልክያስ - መልእክተኛየ
8. ሚክያስ - እንደ እግዚአብሔር ያለ ማን ነው
9. ምናሴ - ማስረሻ
10. ሣራ - ልዕልት
11. ሩሐማ - ምህረት
12. ሮቤል - እነሆ ወንድ ልጅ
13. ሰሎሞን - ሰላማዊ
14. ሳሙኤል - አምላካዊ ስም (የአምላክ ስም)
15. ሳኦል - ከእግዚአብሔር የተለመነ
16. ሴዴቅያስ - የእግዚአብሔር ጽድቅ
17. ሶፎንያስ - እግዚአብሔር ሰውሯል
18. ቃዴስ - ቅዱስ
19. በርተለሜዎሰ - የተለሜዎስ ልጅ
20. በንያስ - እግዚአብሔር አዳነኝ
21. ባሮክ - ቡሩክ
22. ቤተልሔም - የእንጀራ ቤት
23. ቤተል - የእግዚአብሔር ቤት
24. ብንያም - የቀኝ እጄ ልጅ (የደቡብ ልጅ)
25. ቶማስ - መንታ
26. ናሆም - መጽናናት
27. ናታን - እግዚአብሔር ሰጥቷል
28. ንፍታሌም - የሚታገል
29. አልዓዛር - እግዚአብሔር ረድቷል
30. አማኑኤል - እግዚአብሔር ከእኛጋር
31. አርኤል - የእግዚአብሔር ምድጃ
32. አሴር - ደስተኛ
33. አስቴር - ኮኮብ
34. አብርሃም - ታላቅ አባት (የብዙዎች አባት)
35. አቤሴሎም - አባቴ ሰላም ነው
36. አቡ - አባት
37. አብዱዩ - የእግዚአብሔር አገልጋይ
38. አቢያ - እግዚአብሔር ወንድሜ ነው
39. ኢሳይያስ - እግዚአብሔር ደህንነት ነው
40. አቤኔዘር— እግዚአብሔር እረድቶኛል
41. ኢዩኤል - እግዚአብሔር አምላክ ነው
42. ኢያሱ - እግዚአብሔር አዳኝ ነው
43. ኢይዝራኤል - እግዚአብሔር ይዘራል
44. ኢዩሣፍጥ - እግዚአብሔር ፈርዷል
45. ኢዩራም - እግዚአብሔር ከፍ ከፍ አለ
46. ኢዩርብአም - ሕዝቡ እየበዛ ሄደ
47. ኢዮስያስ - እግዚአብሔር ይደግፋል
48. ኢዮአስ - እግዚአብሔር ሰጥቷል
49. ኢያቄም - እግዚአብሔር አቆመ
50. ኢዮአብ - እግዚአብሔር አባቴ ነው
51. ኢዮአታም - እግዚአብሔር ፍጹም ነው
52. ኢዮአካዝ - እግዚአብሔር ይዟል
53. ኤሊዔዘር - እግዚአብሔር ረዳቴ ነው
54. ኤልሳዕ - እግዚአብሔር ደህንነት ነው
55. ኤልያቄም - እግዚአብሔር ያስነሳል
56. ኤርምያስ - እግዚአብሔር ከፍ ያደርጋል
57. እስማኤል - እግዚአብሔር ይሰማል
58. ኬልቅያስ - እድል ፈንታየ እግዚአብሔር ነው
59. ኤድን - ደስታ
60. ኬብሮን - ኅብረት
61. ዘካርያስ - እግዚአብሔር ያስታውሳል
62. ይሳኮር - ዋጋየ
63. ይዲድያ - በእግዚአብሔር የተወደደ
64. ዮሐናን - እግዚአብሔር ጸጋ ሰጭ ነው
65. ዮናስ - ርግብ (የዋህ)
66. ዮናታን - እግዚአብሔር ሰጥቷል
67. ዮአኪን - እግዚአብሔር ያቆማል
68. የካብድ - እግዚአብሔር ክብር ነው
69. ዮዳሄ - እግዚአብሔር ያውቃል
70. ዮፍታሔ - እግዚአብሔር ይከፍታል
71. ጋድ - መልካም ዕድል
72. ጎዶልያስ - እግዚአብሔር ታላቅ ነው
ለሌሎች እንዲዳረስ SHARE እንዲያደርጉ በእግዚአብሔር ስም እንጠይቃለን።
ወስብሐት ለእግዚአብሔር ወለወላዲቱ ድንግል ወለመስቀሉ ክቡር አሜን-ይቆየን።

Thursday, 11 February 2016

IoT is not an IT Initiative, but a Business Function

IoT is not an IT Initiative, but a Business Function 

In future your Bank balance will show if you are an IoT person or not

IoT is the agenda going forward, for many enterprises, but do they really know how to embrace it? Diksha P. Gupta from Open Source For You spoke to R. Ravi vice-president, research & Development, HCL Services Ltd, to figure out how best IoT can help organisations grow their businesses.

What is HCL’s IoT strategy and in what way does the company see itself as the game changer in the IoT revolution?

It all started somewhere along with the ‘Make in India’ campaign, which the government is very keen about and a lot of private enterprises and corporates are also trying to embrace. From that perspective, we thought we could design and build cost-effective end-to-end solutions in the IoT space. Fortunately for us, we have already been operating in the systems integration space for many years, and we had a fantastic platform, or middleware, which we had developed on our own…we have earned IP rights for it. So we thought that it would make sense to build on that and support all the different types of sensors. HCL services have been focusing heavily on three-four industry verticals, including manufacturing, the health care and BFSI. While we do not have any tangible use case for IoT in BFSI, we are trying to focus on manufacturing, automotive, FMCG, logistics and healthcare from the IoT perspective.

IoT is clearly a big buzzword today, but is it anywhere close to reality, w.r.t. adoption, particularly in the sectors you are talking about?

Overall, I think people are just dabbling with the possible business solutions w.r.t. IoT, but I think the automotive industry has taken the lead, with telematics solutions that are already existing. Though these solutions were not called IoT earlier, now the industry is probably adding more features to them. Telematics was initially used for position tracking of the vehicle; now, more features linked to geo-fencing, fuel efficiency, driving behaviour, etc, are being added. That, we feel, will become very common in most of the vehicles going forward, in one or two years down the line. This is one sector in which we see the most traction. The second area in which we see IoT flourishing is that of medical devices. A lot of IoT based medical devices are proliferating in hospitals across Tier 2 and Tier 3 towns as well, apart from the Tier 1 towns.
Likewise, any high value equipment critical for the business environment, will be the next target where IoT will have a solid business case. We had already seen this in data centres in the IT area. Even the non-IT aspects of the data centre, like the AC, UPS systems, chillers, etc, have been using IoT. Though it was not called IoT earlier, it was the beginning of this trend. They wanted the environment to be up and running so that the data centres were always available. The same thing is getting extended to other critical equipment. One sector in which the value proposition will be very high is logistics, where users need to track and trail consignments in real-time. Probably this sector will start late but I think the uptake will be very high.

Could you explain what exactly you meant by IoT concepts being present in some of the sectors even prior to the IoT revolution, but not being referred to by this term.

It was not called IoT because it was not connected to the Internet. Now, with the cloud in place and Internet usage increasing, it is getting reoriented and is known as the IoT. With IoT coming in, the avenues are open for more stakeholders. For example, IoT has led to outsourcing, where the decision-makers are sitting outside the organisation.

The IT industry did witness a slowdown over the past few years. Has the IoT revolution added some pace of the Indian IT industry?

As of now, my answer is, ‘No.’ But yes, IoT will help the IT industry to grow in the years to come. Right now, IoT is a very small portion of the entire IT gamut of operations.

In HCL, how much thrust is given to IoT within the usual projects?

IoT
What we are seeing is that the IT heads or CIOs are not the decision-makers when it comes to implementing IoT-based solutions. It would be either a business or a manufacturing head who would decide whether or not to use IoT. So IoT solutions need to be positioned to them, instead. IoT will be governed mostly by the business value sale and not an IT solutions’ sale.
Of course, the solution pitched to the business heads will be validated by the IT team, because they will have to subsequently handle the support side of things, or it should dovetail into the overall roadmap of automation. This is the reason why we don’t see IoT as a pure IT function, though we do expect it should come down to being a part of IT budgeting, going forward. But as of now, IoT sponsors are business unit heads. So, one may or may not generate an IoT lead by traditionally approaching an IT head. Right now, very few CIOs look at the IoT space, and it happens only in companies where they are a part of the think tank.

What is the stage at which IoT is being looked at, in the Indian enterprise?

We keep doing a lot of ideation workshops with different enterprises. In these sessions, the business heads discuss their business roadmaps, and then we delve deep into different areas where we can enhance business growth, reduce cost or improvise the customer experience, eventually resulting in boosting sales. Taking these issues into account, their internal teams deliberate on what is the priority for them and then we go into the PoC (proof of concept) stage. Right now, a lot of companies are in the PoC stage, when it comes to IoT solutions.

What are the biggest risks associated with the IoT?

The biggest risk the market perceives is security. Today, there are IoT solutions that are sending raw data, and security is at stake. So, this is definitely one key area of concern — to ensure that the data doesn’t go in the wrong hands. The second thing is the absence of the right analytics. IoT-linked solutions will churn out GBs of data on a daily basis, depending on how much data you are collecting and on what frequency. So, it is important that a firm has the matching infrastructure at the backend to gather all that data, and also has the right analytics tools to analyse that data and churn out the right information for informed decision-making. Analytics, in itself, is a developing area and there are a lot of things that still need to be worked out in this sphere. I wouldn’t call analytics a risk, but the growth of IoT will closely depend on how fast the analytics side can grow. So anyone who directly jumps into IoT without having any clarity on analytics may end up in a bad situation – not being able to utilise IoT in a fruitful way.

What single factor, according to you, would accelerate the growth of IoT?

I think a telecom network, supported by analytics and mobility, will lead to the growth of IoT. All the sensors need to be connected by a network, which has to be robust. That is going to play a key role. Also, availability of high data speed at remote locations will fuel IoT growth.

What role does open source technology play in the revolution called IoT?

Analytics is a major factor in IoT. Although we hardly have any open source solutions in the analytics domain, I understand that a lot of groups are working on that. So, that will be a major area where open source will find a role. I think people would not like to spend millions on untested software if they are not sure what business it will deliver. In such a domain, they will probably try open source software. If that works, they will probably go for a commercial licence. The other area where I see open source growing is the cloud, an area of orchestration and provisioning tools.

How, according to you, is the government helping IoT to flourish in India?

It is too early to talk, but I think the Smart Cities initiative is going to be a very big consumer of IoT. Smart cities would need different types of sensors offering various controls, tracking, parking solutions, infrastructure facilities to monitor the transformers, sub-stations, telecom towers, maintenance facilities, etc. Ultimately, all of these cannot be done manually. This is where IoT will come into play.

Is there one piece of advice that you want to share with the business leaders who want to embrace IoT?

The simplest thing that they can immediately embark on is the ideation session, if not done already. They should identify, not one, but five to six areas in which IoT can be used to improve the level of automation. The key thing is that IoT should be treated as a solution to solve business problems and as a business enhancement tool, and not an IT initiative.



Shanosh Kumar

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Monday, 8 February 2016

Selecting The Right Operating System for Your Next Embedded Design




From robots, cars, home appliances to calculators, thermostats, ATMs and mobile phones, embedded systems are everywhere. And at the heart of almost every embedded system is its operating system (OS), which plays a critical role in keeping the system alive and running. “Therefore it is essential to choose the right OS at the very beginning of the design cycle itself,” notes Neeraj Saraf, CEO, Seal Technologies. Let us explore the important parameters that must be considered while selecting the perfect OS for your embedded application.

An OS can greatly affect the development of the design. According to Andrew Longhurst, engineering and business development manager, Wittenstein high integrity systems, by selecting an appropriate OS, the developer gains three things: one, a task based design that enhances modularity, simplifies testing and encourages code re-use; two, an environment that makes it easier for engineering teams to develop together; and three, abstraction of timing behaviour from functional behaviour, which should result in a smaller code size and more efficient use of available resources.
 

Peripheral support, memory usage and real-time capability are key features that govern the suitability of the OS. Longhurst says, “Using the wrong OS, particularly one that does not provide sufficient real-time capability, will severely compromise the design and viability of the final product. The OS needs to be of high quality and easy to use.” He adds, “It is hard enough developing embedded projects and you do not want to be struggling with OS-related problems as well. The OS must be a trusted component that the developer can rely on, supported by in-depth training and good, responsive support.”


In the case of systems with real-time characteristics, a hard, real deterministic OS would be the right choice, whereas for applications that require no real-time behaviour but run a set of applications with rich user experience, an embedded Linux with a good graphics library or Android would be the right fit, informs Thilak Kumar, manager, field engineering, Wind River Systems. Therefore choosing the right OS early in the design cycle is very important. He says, “If it is not realised, it could put the entire project at risk, especially if the OS is unable to meet key system requirements.”

On another note, Mubeen Jukaku, technology head, Emertxe Information Technologies, feels, “Design engineers should be able to create a design with effort spent in creating the application rather than other factors specific to the OS.”

Now that we know the importance of choosing the right OS for developing embedded systems, let us take a look at the parameters to be considered for selecting the same.

Selecting the OS 
Embedded systems are meant to run for long, and sometimes these are unattended or non-upgradable. In any case, these should be robust, reliable and secure. “Support for device drivers, ease of porting and extending/configuring the kernel also matters a lot if devices are peripheral-rich and you have future plans of upgrading the hardware,” says Jukaku. For power management, the OS should be able to provide power-saving features, like suspend/wake-on-interrupts. He adds, “Some other factors include availability of software protocols and development libraries, which could be specific to the application area. The level of vendor/community support for the OS also needs to be high.”


While designing an embedded system, parameters such as computing power, memory, electrical power, real-time behaviour, regulatory guidelines, connectivity, safety, security and manageability should also be considered while selecting an OS. Citing an example, Kumar says, “If you are designing a life-critical device, such as a pacemaker, then the OS would need to be deterministic, small and extremely power efficient.” He adds, “If you are designing an avionics system, it would still need to be power efficient but not as much as the pacemaker. For sub-systems, meeting safety requirements outlined by the regulatory authority is one of the most important requirements and a certified/certifiable OS would be more appropriate.”

For developers, real-time operating system (RTOS) selection has traditionally been a matter of preference and convenience, as they tend to look at compatibility with their choice of compilers, debuggers and other development tools, informs Prasad Suri, AVP-sales, product engineering services, ValueLabs. He says, “Many use integrated development environments (IDEs) that enable them to develop a wider range of RTOSs.”

Another critical factor for the success of a project is the selection of an OS that ensures right time to market for the application. Suri adds, “RTOSes that offers simple system services, intuitive naming conventions, documentation, good support and availability of full source code should be preferred as these characteristics enable developers to become productive in a short period and complete projects on schedule.”

Trends in selection of an OS
“We have seen an increase in the use of multi-core devices,” notes Longhurst. This presents an interesting challenge to OS suppliers, as the OS also needs to support core-to-core communication and asymmetrical and/or symmetrical processing models. He adds, “The type of OS support required is highly dependent upon the architecture of the application. Therefore a one-size-fits-all approach is not appropriate, as each solution will require a certain amount of customisation to achieve an optimum design.”


Another obvious trend is related to the Internet of Things (IoT) or machine-to-machine (M2M) communication, where embedded devices that existed in isolation in the past need to be connected now. Kumar says, “Connectivity is essential for better manageability of assets, which allows businesses to move from a device-centric model to a service-oriented model. With connectivity, there is also the threat of security that needs to be addressed.”
The other very prominent trend is software defined networking (SDN) and network function virtualisation (NFV). He adds, “This is driving consolidation of efforts in the networking and telecommunication markets where delivering carrier-grade reliability, while also achieving high-performance throughput with minimal latency, is absolutely essential.”

Platform era. There has always been a need to tailor-make embedded OSes for specific application domains. Many times this is like re-inventing the wheel and often unnecessary. Jukaku notes, “Recently, there has been a trend in building domain-specific OSes or software stacks that consist of the OS, application stack, framework and development environments—commonly known as platform.” Citing an example, he explains, “In the automotive industry, there is automotive-grade Linux, which is a Linux based software stack for the connected car. Google is also bringing Android to the car with Android auto. Similarly, in the IoT space, ARM has come up with mbed OS for IoT devices.”

Adoption of open source. Another trend seen is the wide adoption of open source software in the embedded space. Jukaku says, “Organisations are adopting open source software because of their reliability, stability, accuracy, cost, openness and support.”


Choose wisely, build effectively
It is not only the OS functionality and features that you will need to consider, but also the licensing model that will work best for your project’s budget and the company’s return on investment. Longhurst says, “The company behind the OS is just as important as selecting the correct OS itself.” He adds, “Ideally you want to build a relationship with the OS supplier that can support not only your current product but also products of the future. To do this, you need to select a proactive supplier with a good reputation, working with leading silicon manufacturers to ensure they can support the latest processors and tools.” Trust, quality of product and quality of support is everything.
 

From skill point of view, Jukaku says, “Understanding the architecture of the OS, integrating appropriate board-support packages, hardware interfacing and customising, and tuning for specific needs are all very important to have.” These skills make the OS easier for a new product designer to get started with.

Ultrasonic Radar Model Using Microcontroller ATmega128



  
Radar systems have a number of defence as well as civil applications. Air traffic control uses radars to track aircrafts on the ground and in the air, and to guide planes for smooth landings. Police use radars to detect the speed of passing vehicles. Geologists use radars to map the Earth and other planets. Military uses these for surveillance. Meteorologists use radars to track storms, hurricanes and tornadoes. The list is endless.
 

A radar system consists of a transmitter that transmits a beam towards the target, which is then reflected by the target as an echo signal. The reflected signal is received by a receiver. This receiver processes the received signal and provides such information as the presence of a target, distance, position (moving or stationary) or speed, which is displayed on a display unit.
 

Circuit and its working 
Actual radar systems are built with high-power transmitters and receivers, huge antennae, complex processing systems using digital signal processors and large displays.
The circuit described here demonstrates the working of a radar system. It uses ultrasonic waves to detect an object and measure its distance and angular position, and displays the same on a 20x4 LCD screen. It can detect multiple objects at different angles and distances as new objects are detected. This means that the distance and angle of all objects are displayed one by one on the same LCD screen.
The block diagram of an ultrasonic radar system is shown Fig. 1. The system includes an ultrasonic distance measurment (UDM) sensor, LCD panel, opto interrupt sensor, a motor driver, DC motor, buzzer and LEDs. The schematic of the system is shown in Fig. 2.

Fig. 1: Block diagram of an ultrasonic radar system
Description of components 
Microcontroller (ATmega128). AVR microcontroller ATmega128 (IC3) is a high-performance, low-power Atmel 8-bit AVR RISC based microcontroller that combines 128kB of programmable flash memory, 4kB SRAM, 4kB EEPROM, 8-channel 10-bit A/D converter and JTAG interface for on-chip debugging. The device operates between 4.5V and 5.5V.
Ultrasonic distance sensor. This sensor is a modified version of the original UDM sensor. The UDM sensor module has four pins but this module has only three pins for connection to external circuit. The transmitter unit sends an ultrasonic wave of 40kHz directed towards the target. The reflected signal is received by the receiver unit, which calculates distance based on the speed of ultrasonic waves and the time required by the waves to travel to-and-fro.


Fig. 2: Schematic diagram of the ultrasonic radar model using microcontroller ATmega128

  
It forms a 9-byte frame as xxx.xxcm of the calculated distance and sends it through a serial (UART) interface to the microcontroller at pin PE0 configured as RXD0. The sensor works on 5V DC power supply. Its minimum and maximum ranges are 10cm and 400cm, respectively. The rate of transmission of the serial data is 9600bps with TTL level output. The ultrasonic distance sensor is shown in Fig. 3.
The sensor can be easily interfaced with any microcontroller. Output from the sensor is in a frame of nine bytes. The frame format xxx.xxcm is described in Table I.
Slotted opto isolator module MOC7811. Internally, the module consists of an LED and a photo transistor. The plastic package encloses them in such a way that there is gap in between these two components as shown in Fig. 4. If the LED is forward-biased, its light falls directly on the base of the photo transistor and it conducts. But, if any obstruction like a thin strip, card paper or post card is placed in the gap, the light does not fall and the photo transistor does not conduct.

Fig. 3: Ultrasonic distance sensor—serial out module

Fig. 4: Slotted opto isolator module MOC7811
  
DC motor driver IC L293D. L293D (IC2) contains two in-built H-bridge driver circuits. In its common mode of operation, two DC motors can be driven simultaneously, both in forward and reverse directions. The operation of the two motors can be controlled by input logic at pins 2 and 7, and 10 and 15. Input logic 00 or 11 will stop the corresponding motor. Logic 01 and 10 will rotate it in clockwise and anti-clockwise directions, respectively. In the circuit, it is programmed to run 5rpm DC motor in a clockwise as well as anti-clockwise direction. In this circuit, the input logics are fed to pins 2 and 7 to control the motor connected across pins 3 and 6 of IC2.
LCD panel. The 20x4 LCD displays the scanning angle, measured distance, messages like Object Detected and Scanning, etc. It accepts ASCII value of any letter or digit and displays it on the selected line.
LED dial. Twelve red-colour LEDs are arranged like a dial of clock. Each LED indicates an angle between 0o and 330o that is separated from the next or previous by 30 degrees. When an object is detected, its angle is indicated by the corresponding angle of LED. This gives an approximate idea of position, direction and angle of an object with respect to reference position.
Buzzer. It is a piezoelectric DC buzzer that generates audible beep-like sounds when given DC supply of 5V. It is used to give short beep sounds on detection of an object.
Opto interrupt sensor circuit. This circuit generates a negative pulse when the strip passes the gap in the sensor. This pulse is used to generate an interrupt signal for the microcontroller. As shown in Fig. 2, the circuit comprises a slotted opto isolator module, BC547 npn transistor T1 and a few resistors.
The internal LED is forward-biased through the current-limiting resistor of 330Ω. This turns it on continuously. The falling LED light drives the photo transistor to saturation. Its output at the collector is low, which drives T1 into cut-off. This means that output of the circuit is high, which is the normal state when the falling light is not interrupted. When a strip passes through the gap, it blocks the light and the photo transistor goes into cut-off.
Its output at the collector is high, which drives transistor T1 into saturation and gives low output at its collector.
As the strip passes through the gap, we get high to low, which is taken as interrupt. Interconnection of various components with microcontroller ATmega128 (IC1) is shown in Fig. 2 and described below.
1. Serial data output pin Tx of the sensor is connected to PE0 of IC3. 
2. Opto interrupt sensor interfacing circuit is connected to external interrupt 4 pin at pin 6 of IC3.
3. Pins PB5 and PB6 of PORTB are connected to inputs (IN1 and IN2) of L293D chip. These pins are used to rotate the motor clockwise and anti-clockwise. Pin PB4 is connected to enable input of L293D chip, which is used to enable the output of the chip.
4. DC motor is connected to two outputs (OUT1 and OUT2) of L293D (IC2).
5. Pin PF0 of PORTF is connected to operation (scanning) LED17 through current limiting resistor R19. Another pin, PF1, is connected to the buzzer through npn transistor (T2) BC547. 
6. PORTA pins PA4 through PA7 are connected to data pins D4 through D7 of the LCD. Pins PA0 and PA2 are connected to control pins RS and EN of the LCD, respectively. R/W pin of LCD is connected to ground.
7. LCD pins 2 and 15 are connected to Vcc, the latter through 100-ohm resistor R20, and pins 1 and 16 are connected to ground. Pin 3 of the LCD, which is used for contrast control, is connected with 10k pot, as shown in the figure. 
8. PORTC pins PC0 through PC7 are connected to cathodes of eight LEDs. Anodes of all the LEDs are connected to Vcc through current-limiting resistors.
9. Similarly, four PORTG pins PG0 through PG3 are connected to four LEDs. 
10. The 12MHz crystal with two 22pF capacitors is connected to pins XTAL1 and XTAL2. 
11. The complete system works on 5V DC supply, with additional 12V DC supply given to pin 8 of L293D (IC2) for the DC motor.

Fig. 5: An actual-size PCB of the circuit

Fig. 6: Component layout of the PCB
Download PCB and component layout PDFs: click here

System operation

1. Initially, the motor is stationary and the strip is in the gap of the slotted opto isolator module. This is the reference angle 0o (position) for ultrasonic sensor module.
2. Next, the motor starts rotating in a clockwise or anti-clockwise direction. The speed of the motor is 5rpm, so we can presume that in one minute (60 seconds) it completes five revolutions. So, to complete one revolution, it takes 60/5 = 12 seconds. 
Now, one revolution = 360o, which means in 12 seconds the motor will rotate by 360o, and in one second, it will rotate by 30o. Thus, to rotate the motor by 30o, it has to run for one second only. Furthur, to reduce the speed of the motor to 2rpm only, after moving the motor by 30o for one second, the motor rests for 1.5 seconds and then moves in a clockwise or anti-clockwise direction, depending on the direction of previous rotation.
3. As the motor rotates in clockwise or anti-clockwise direction, messages such as Scanning......, Angle:30, Angle:60, Angle:90, etc, are displayed on the LCD. 
4. When the motor rotates completely by 360o in 30 seconds, the strip again passes between the gap of the slotted opto isolator module. This generates an interrupt signal and the motor starts rotating in 30o steps at a speed of 2rpm in reverse direction, and messages are displayed on the LCD as Scanning......, Angle:330, Angle:300, Angle:270, etc.
5. Same thing happens when the motor reaches back to 0o. Thus, the cycle continues and the motor rotates clockwise and anti-clockwise continuously to scan a complete 360o at the rate of 2rpm.
6. The sensor module continuously sends ultrasonic waves of 40kHz and receives echos. If it receives an echo from any object, it calculates the distance and sends it serially to the microcontroller, which displays the message Object Detected, and the distance of the object as distance = xxxcm on the LCD. The angle at which the object is detected is indicated approximately by glowing LED. It also generates short beep sounds on the buzzer for audio indication.
Construction and testing
An actual-size, single-side PCB of the circuit is shown in Fig. 5 and its component layout in Fig. 6. The slotted opto isolator module, ultrasonic sensor and DC motor are external to the PCB. These are connected to the PCB through connectors provided on the PCB.
Make a separate circular dial. Refer the proposed system set-up as shown in Fig. 7 for fitting the LEDs (LED1 through LED12) and connect these through wires from the PCB. The prototype set up in EFY Lab is shown in Fig. 8.
For troubleshooting, first check the voltages at various test points as listed in Table II. 

Fig. 7: Proposed system set-up

Fig. 8: Prototype set up in EFY Lab
Software program
The program for the microcontroller is written in C language and compiled using AVR Studio 4. The compiler is used to convert C program into a hex file for burning into the flash memory of ATmega128 microcontroller using AVR Studio 4. A 4-pin connector (CON2) is provided in the circuit for programming the chip using a suitable ISP-compatible AVR programmer board.
 

The complete program is a combination of different functions. It starts with the main function, which is used to configure various ports of ATmega128 microcontroller as input/output (I/O) and initialise the LCD. It also calls UARTinit() function to initialise UART0 to 9600bps and enable reception. The main function also enables interrupts to be used in the project and continuously rotates the motor in either direction (clockwise or anti-clockwise) at 2rpm.
The function angle_disp() is used for displaying the corresponding angle of the rotation of ultrasonic sensor module from its point of origin. There are two interrupt handler sub-routine functions, ISR(UART0_RX_vect) and ISR(INT4_vect), which represent operation mode on receiving interrupts.
ISR(INT4_vect) is used to set reference for the angle and operation of the motor in the opposite direction to the current direction of the rotation of the motor. ISR(UART0_RX_vect) receives nine bytes from the sensor, calculates the distance of the object from the sensor, and displays it on the LCD screen. As soon as an object is detected, the buzzer sounds and indicates the angle of object detection on the LCD as well as on the LED dial with corresponding LED indication.
All LCD functions, such as lcd_init(), lcd_cmd(), lcd_str() and lcd_num(), are included in LCD header file lcd.h.

Download source code: click here