Dilshan R Jayakody’s Web Log

In this project we decide to implement simple ATMEL AVR microcontroller programmer for our hobby electronic purposes. We get ideas for this project from http://www.electronics-diy.com and http://www.societyofrobots.com . All the credits of this project go to them and creator of the ISP Programmer - Adam Dybkowski. You can get complete circuit diagram from here Entire project is based on the 7408 - Quad AND gate chip and it is possible to use any (CMOS/TTL) AND gate chip with this project. During the testing phase we use CD4071 and 7409 quad AND gate chips without any circuit modifications. During the assembly process make sure to install proper heat-sink to the 7805 voltage regulator. After constructing the circuit download and install ISP Programmer and follow these steps, Open ISP Programmer software package and press "Setup" button to setup the programmer. Select "AEC ISP" as a "ISP Cable Pinout" and press OK Connect MCU to the programmer and power on...

Microsoft compiled HTML help files are now commonly used in software applications and generally these files are opened using hh.exe (HTML Help) file in windows folder. The most important thing is, hh.exe have custom chm decompilation command. To use this option simple provide following parameters to hh.exe, hh.exe –decompile for example : hh.exe -decompile E:\test\output E:\test\help_demo.chm That’s all. Check the output directory for all HTML topics, Images and other related files.

In this project we design 9 pin Microsoft Windows NT compatible dot matrix printer using two PIC16F84A microcontrollers. Printer mechanism is based on old Commodore dot matrix printer. At the moment this device support for Microsoft Windows 2000 and XP operating systems. Other most notable features of this implementation are, Drive 18V - 9pin magnetic dot matrix head unit Handle 12V paper feeder and head movement stepper motors Support A4 and compatible page formats System drives using 240V - 18V step-down transformer Audible warning system Low power consumption due to CMOS implementation Works with Standard Printer Port In this implementation we use Microsoft Windows Driver Development Kit (DDK) with Microsoft Visual C++ to create device driver for the system and use Delphi 7 to create front end application (printer maintenance – control panel applet). Both microcontrollers are programmed using MPLAB – ASM. In this system we use 2 microcontrollers with 7MHz oscillators, One PIC16F84A ...

Universal Serial Bus (USB) allows peripherals and computers to interconnect using standard protocol and provide plug and play feature to the devices. At the moment there are 2 specifications available for USB they are, USB 1.1 : In this specification data transfer rate is 12Mbps and 1.5Mbps. USB 2.0 : Support data transfer rate up to 480Mbps. Both these specifications support up to 127 devices and support for hot swapping (no need to power down to remove or connect the devices). In USB devices are categorized as a classes and each class represent the functionality that target device can provided to the host device. For example: AUDIO : Audio and related systems HID : Human Interface Devices. (E.g: Keyboard, Mouse, etc) POWER: Devices related with the power such as UPS systems. IrDA: Infrared devices. There are 4 types of transfers take place over USB, Control transfer : Used to configure the bus and devices on the bus. Bulk transfer : Move data asynchronously over USB. Isochron...

I’m trying Delphi for PHP 2.0 in few days back and I'm get very frustrated about it because of its pour implementation and technologies. Some key failures in Delphi for PHP 2.0 are, - IDE is very buggy and most of the times it produces "Access Violation" errors and IDE get confused. (In my computer Delphi 7 tries to debug it.) - Help is very pour and incomplete. - JavaScript and PHP integration is very complex and buggy. Most of the time JavaScript codes may not work in client side and it is heavily depends on the web browser. - Some times it is necessary to deploy entire "VCL" directory to the web server otherwise some of the VCL components produces invalid outputs. (specially RichEdit and TrackBar components) - MySQL integration is pour and buggy. - Build-in Apache web server crash several times and because of that reason we may not be able to debug/run web application using IDE. - Some times XML file (xml.php) generated by Form Designer may not compatible wit...

According to my experiences USB devices are bit complicated to design and writing software (drivers and support applications) for USB devices are time consuming and complex process. Most recommended (and easiest) method to design hardware interface for USB port is using Future Device Technologies FT245 or FT232 chips. At the moment both these chips support for USB 2.0 and have excellent set of APIs. To test the performance of this device I implement some experimental version of PC oscilloscope using FT245 USB Interface, AD7575 ADC, LF347 Op-amp, 4069 Hex Inverter and array of AM7205 FIFOs. Application program is design using Delphi 7 and it is totally based on FTDI Delphi APIs. This test system is worked perfectly in Windows XP and Windows 2003 systems during my test runs and produce excellent results. I choose FT245 for this design because it has 8 parallel input interfaces and this is perfectly matched with AD7575 ADC. (AD7575 also have 8 parallel outputs) I use 2705 FIFOs to captur...

Thoppigala is a computer game developed by Vectronics and according to my observations it is developed using Game Creators FPS Creator. I have demonstration version of Thoppigala game and it is totally based on FPS Creator models and FPSC Model Pack 5. The vendor (Vectronics) do model’s texturing part only. Demonstration mission available in this release (file version 1.0.0.0) is based on the FPSC sample mission and it’s level designing is in very poor stages. In this game, player use Tommy Gun (Thompson Submachine Gun) for it’s operations, but the problem is according to my knowledge Sri Lanka Army may never use Tommy guns for there operations and it is widely used in World War II and currently it is not in use. FPSC model pack 5 contains good weapon collection and I don’t know why designers may not use them for these missions. This game have lot of other problems, most notable problems are, Enemy AI : During the attacks, and all the others just choose some random direction to run in,...