Tuesday, July 28, 2009

The Best PIC Microcontroller Projects on Web (Part 1)

In this section of my blog, I have planned to compile a list of some of the best PIC microcontroller based projects that are available online. Since there are many, they will be discussed here in a series of articles. This is the beginning. I hope this will help those students and hobbyists who really want to do something on PIC interfacing but getting hard time to find a good project to start with. These projects are really some of the best electronic projects based on PIC microcontroller interfacing. Meantime I also believe that there could be some others too that might have been overlooked by me. I would appreciate for your time and effort if you would like to provide the links of any other projects that you think should be listed here.

I have selected these projects out of hundreds on the basis of their completeness, explanation detail, and uniqueness.

1. An Alarm Clock Based on PIC16F84A

If you are looking to build a simple alarm clock based on a PIC 16F84A, this is a perfect choice. This clock counts seconds, minutes, hours and day of the week. The display portion consists of 4 seven segment LED displays, and the clock can be programmed with three push buttons. For the circuit diagram, program, and other details, CLICK HERE ....

2. PIC16F628 Based Frequency Counter

This is a very cool project based on PIC16F628, and I am pretty sure you will love to do it. The frequency range of this counter is 1Hz to 50MHz, and has automatic range switching capability. This project uses very minimum number of components and can be built on a single-sided general purpose proto-board. For more details, CLICK HERE ...

3. Digital Thermometer

This is another project based on PIC16F628, and a 1 wire digital thermometer IC DS1820. It uses 16x2 LCD screen for temperature display. It has a relay switch to control any system based on surrounding temperature. For details, CLICK HERE ...

4. A VGA Test Box

The goal of this project is to develop a VGA test equipment that is capable of generating VGA signals that could be fed to a monitor to display figures and text. The good thing about doing this project is it will give you a chance to learn about how CRT monitor works, as well as the importance of timing and synchronization in displaying output on a monitor screen. This uses PIC18F452 microcontroller with a 4MHz oscillator. For detail schematics and description, CLICK HERE...

Saturday, July 25, 2009

Where to buy low cost PIC Programmers?

In this blog I am going to talk about some low price PIC programmers from different manufactures and the places to buy online. Their price range is less than $60.00 and some of them have really very good shipping rates.

1. MCUMALL (www.mcumall.com)

I exactly don't know where they are located but last month I ordered a PIC programmer and it was shipped from China. They have a wide variety of PIC programmers online ranging from $17.99 to above hundred, depending upon your requirements.

(i) PRG-022 Enhanced JDM PIC programmer

The cheapest one is PRG-022 Enhanced JDM PIC programmer. It is the most popular JDM type PIC programmer that comes with a RS232 cable and a link to download necessary software. However, this product does not work on Windows Vista. It has on board ICSP Header that let user program the chip In-Circuit. The price for this product, as mentioned on their website is $17.99.

(ii) PRG-017 USB PIC programmer

This is a low cost USB based PIC programmer that can be used in Windows Vista platform too. It acquires power from the USB port itself, and works on laptop which has no RS232 serial port. This can program a wide variety of PIC devices. The complete list can be found on the website. The price for this item is $24.99 on their websites, and it comes with a link for software and a USB cable.

2. Softworld (http://www.alibaba.com/product/pk105521569-105221534-0/PIC_Programmer.html)

This is the cheapest PIC programmer I have ever seen on web
(just $8.00, can you imagine?). These guys sell this product through www.alibaba.com and they are located in Pakistan. This programmer supports a wide variety of 16F and 18F PICs. An Excellent Offer to Hobbyists and Students!

3. iCircuit (www.piccircuit.com)

This is another cheapest PIC programmer I have seen on web. It does not come with any ZIF socket. It is an In-Circuit Serial Programming (ICSP) with USB interface with PC. It can be used for programming the popular Flash PIC MCU, includes PIC10F, PIC12F, PIC16F and PIC18F family, and it does not require any additional power supply. It supports both Windows XP and Windows Vista. The cost is only $15.00. If you are willing to pay $22.00 you will get both the ICSP programmer and 40 pin ZIF adaptor.

4. FUTURLEC (www.futurlec.com)

This is an online electronic store and they sell wide range of electronic components: from tiny LEDs to microcontroller development boards. I had made two deals with these guys a couple of months ago, they have really very low prices of electronic components. But I would say they are little bit slow in their shipping, but the prices are great.

(i) PIC Programmer - USB Connection

If you go to Boards -> Programmers section on their website, you will see this product. They mention the price for this product $59.00. It has two ZIF sockets so as to program 8-40 pins PIC microcontrollers. It derives power from USB port, no external supply is required. In-circuit programming is also available with a wide range of adapters (sold seperately). It comes with a Windows version programming software.

(ii) PIC18F458 Development Board

This is a PIC development board that comes with a PIC18F458 microcontroller pre-installed with all the necessary support components included. It has a large breadboard area for additional circuitry and testing. All the input/output ports are available through female header pins. The power supply is not included and need to be purchased seperately. If you have purchased a PIC programmer seperately, this item will be very useful to start developing PIC projects without much discomfort. The price for this item is $30.90 online.

5. KEE Electronics (www.keeelectronics.com)

The physical location of this store is not mentioned on web (most possibly in China), but they have four varieties of PIC programmers, all under $50.00.

(i) ICD2.5 Debugger with PIC Programmer ($49.95)

(ii) PICkit 2 Development Programmer/Debugger ($38.00)

(iii) USB Microchip PIC Programmer ($34.00)

(iv) USB Microchip PIC Programmer (JB3 Chip Burner) ($37.00)

Please visit the website for detail specifications of these products.

6. Total Project Solution (www.onlinetps.com)

TPS is an Indian based company that sells a serial port PIC programmer for IRs 700.00 (equivalent to $18.00 approximately). It can program more than 150 different PIC devices from 8- to 40-pins. It does not require any external power supply and it comes with a software CD and a RS232 cable. Students and hobbysts from India, Nepal, Pakistan, and Bangladesh may save shipping time and cost with this purchase if they are looking for a simple and low cost PIC programmer.

7. e-bay

Shopping on ebay has become very popular these days, as the prices are comparatively cheaper on ebay stores. You can find a large number of stores on ebay selling PIC programmers. I have listed the names of few stores where you can find PIC programmers at a good price.

(i) QLS_Microchip pic mcu/mpu tools

(ii) Stella Collectible and Electronics

(iii) I_Wanne_Buy_Shop


(v) sureelectronics3

(vi) sivava store

(vii) MDflystore

Friday, July 24, 2009

Basics of Microcontrollers (Part 2)

This is the follow up from Part 1

How it differs from a Microprocessor

Microcontrollers are special-purpose computer systems, usually programmed to perform a single task. However, a microprocessor is tasked to perform a wide variety of functions. For example, a microcontroller in a traffic light control system is dedicated to timely switch ON and OFF the various switches so as to allow smooth traffic flow. On other hands, a microprocessor inside a desktop computer can do a wide variety of jobs depending upon the user inputs. As a matter of fact, a microcontroller has a built in microprocessor too that executes the instructions loaded in its memory.

Example of microprocessors: Intel 8085, 8086, Pentium, etc

Programming Microcontrollers

A microcontroller can do nothing without it is instructed to do something. The instructions can be loaded into its memory so that it could execute them repeatedly and perform the task it is supposed to do based on those instructions.

Most of the modern microcontrollers have Flash EEPROM to store the instructions. It means you can erase the old instructions and reprogram. You need a programming device to do this. There are many companies who build these programming devices. A few websites where you can buy microcontroller programmers are listed here:

1. http://www.alibaba.com/showroom/microcontroller_development.html
2. http://www.hobbyengineering.com/
3. http://www.sparkfun.com
4. http://www.futurlec.com/Programmers.shtml
5. http://www.digikey.com/

You can find many more on google search.

Additional features of Microcontrollers

Microcontrollers are available with extra features such as analog-to-digital converters (ADCs), watchdog timers, controller area network (CAN), and so on. With an inbuilt ADC, you can directly connect an analog input to the microcontroller. Similarly, a watchdog timer is a piece of hardware that can be used to automatically detect software anomalies and reset the processor if any occur.

A typical example of how microcontroller work?
Source : http://www.maxim-ic.com/products/microcontrollers/designers_overview.cfm

Let's examine how a microcontroller functions while cooking a bag of popcorn in a microwave oven.

You open the door and put the bag of popcorn inside. You close the door and push the button labeled "Popcorn." A few minutes later, a tone announces the popcorn is done. What happened behind the scenes?

When you opened the door, the microcontroller sensed the door switch, turned on the light and disabled the magnetron. The microcontroller continually scans the keyboard. When you pushed the "Popcorn" button, the microcontroller confirmed that the door was closed and began to count timing pulses, started the motor for the turntable, set the power level of the magnetron, and controlled the display. When the timer reached zero, the microcontroller shut down the magnetron, stopped the turntable, and signaled you.

Wednesday, July 22, 2009

Basics of Microcontrollers (Part 1)

In this section of my blog, the most fundamental aspects of microcontrollers will be discussed. This includes the definitions of a microcontroller and the relevant terms, types of microcontrollers, and microcontroller programming. Enjoy!

What is a Microcontroller?

A microcontroller is a complete computer system on an integrated chip, typically combining a Central Processing Unit (CPU), memory units (RAM, ROM), and I/O ports so that they can function as a tiny, dedicated computer. The input ports are used to detect action by a user or read input from attached sensors (e.g., light, heat, motion sensors), whereas the output ports are to display the results (on LEDs, LCD Display, Monitor, etc) of processing based on the inputs, or to take any actions (like switching on/off devices, send messages to remote stations, etc). In the physical sense, the I/O port relates to metal pins on the part package that are used to connect to other circuitry in the system. Microcontrollers usually have just a few I/O pins, as few as 8 or as many as 100.

Microcontrollers are everywhere.

Microcontrollers have become common in many areas, and can be found hidden in many categories of products like home appliances, computer equipments, automobiles, etc.
A microwave oven with a LCD screen and a keypad contains a microcontroller. Microcontrollers are used in running the traffic light at an intersection. In automobiles, the engine, the anti-lock brakes, the cruise control, and so on, are all controlled by microcontrollers these days. From the simplest gadgets, like digital cameras, cell phones, printing machines etc, to highly sophisticated satellite and rocket missile systems, the microcontrollers have become ubiquitous.

How does a microcontroller look?

Figure 1(a). PIC16F628 microcontroller

Figure 1(b). Pin description of PIC16F628

Figure 1(a) above shows a 18 pin microcontroller named PIC16F628, manufactured by Microchip company. The metal pins are Input/Output and power supply pins. The description of the various pins of PIC16F628 is shown in Figure 1(b). You don't have to understand the detail functions of these pins at this point. Just move ahead.