Friday, July 16, 2010

Cara Mrogram mikrokontroller AT89S52 Mengunakan Programmer 2.15

Mrogram mikrokontroller AT89S52 Via Programmer 2.15

Programmer 2.15 is a software specifically developed for programming, read, or erase the internal flash memory microcontroller AT89S52, Programmer2.15 also equipped with a text editor that can be used to create the program in 8051 assembler language and compiled directly in to the file hex

Programmer 2.15 windowPic 1. Programmer 2.15 window

How to use Programmer 2.15
  • Programmer2.25 is equipped with a text editor that functions to make programming in assembler language.
  • When finished making your program can compile directly using a shortcut assemblel / compile it (F9), if it found an error from the program list, programmer 2.51 will display an error message, and if there are no errors will appear the message "NO ERRORS FOUND"
  • after the compile process successfully you can directly write down (the download) to the flash memory at8951/52

How to program (to download) to the flash memory AT89S51/52

Assembler program that has been compiled with no errors can be directly in the programming or "the downloaded" to the flash memory AT89S51/52. Programmer 2.15 using parallel port for this download process. Also in need a special interface circuit such as circuit scheme is shown below.

rankaian antarmuka Programmer 2.15
rankaian antarmuka Programmer 2.15Pic 2. rankaian antarmuka Programmer 2.15

Before doing the download process needs to be done beforehand setting process, the setup process is done using a programming menu / setup (See figure 1.) Settings are done to select the parallel port address, memory lock bits mode, and determining conditions RST pin after the download process completed

Pic 3. settings window

  • Adjust settings such as the picture above
  • LPT1 address customize to your computer
  • Programmer2.15 suitable for programming (download) Microcontroller AT89S51/52
After doing the settings in the process of programming can be done through programflashmemory menu (F2)


Wednesday, July 14, 2010

Menghitung Resistor LED Putih (Super Bright White LED)

LED (light emitting diode) is currently being widely used, among other things, traffic signal lights and indicator lights of the vehicle. Efisasi value (lumens per watt) LED increasingly make this light source is used widely in the field of lighting.

LED Super Bright Nyala PutihSuper bright white LED pic

LED is highly efficient light sources. Average white LED lamps that are marketed produce light efisasi of 32 lumens per watt (lm / W), and the results of the latest technological development is expected to produce 80 lm / W. LED operating life which has made a long-white LED light is very attractive.

Menghitung Resistor LED Super Bright Nyala Putih

The following formula to calculate the required resistance is as follows:

R = (Vs-Vd)/Id

  • R = resistance is needed (Ohm)
  • Vs = voltage source / power supply (Volt)
  • Vd = LED forward voltage (Volt)
  • Id = LED forward current (Ampere)
Lights will be used 3 pieces LED, when the voltage source using a 12 VDC car batteries. The question now, what is the ideal resistor values to inhibit voltage 12VDC, so that the LED does not die quickly?

So, (-12V (3.6 V * 3)) / .03 A = 40Ω

Thus, the resistor value for 3 pieces LED lights that are installed in series 20Ω

how to install it as below
Rangkaian LED Super Bright Nyala Putih
  • The voltage (Vd) and current (Id) white LED can be seen in the datasheet below
Datasheet 500TSW4DF Super Bright White 5mm LED
  • DC Forward Current 30 mA
  • Reverse Voltage (IR = 100mA) 5 V
  • Forward Voltage 3.6 - 3.8 V
  • Peak Pulse Forward Current (1) 100 mA
  • Avg. Forward Current (Pulse Operation) 30 mA
  • Operating Temperature -30 to +85 0C
  • Storage Temperature -40 to +100 0C


Monday, July 05, 2010

Cara Menentukan Nilai Resistor Pada LED

Menentukan Nilai Resistor Pada LED

How to choose a resistor to turn on the LED? Why LEDs need resistors? That's because the LED does not have a current regulator, the LED will burn out if no resistor.

The amount of flow determines how bright an LED. Greater flow of the lighter flame of an LED. Current in the LED should be approximately 10-20 mA. When a current passes through a LED, the LED voltage drop of about 1.85 V or depending on the type of LED that is in use

LED picLEDs Pic

To determine the resistor on the led first consider the graph above (right graph ). Choose the desired LED light and use this chart to determine the required flow. For example, if the desired luminous intensity (high / dark light an LED) for 1, can be seen that the currents are in need of 20 mA.

This shall mean the current 20 mA to pass through the LED, to get the brightness of LED = 1. Now, we can calculate the voltage drop across the LED based on a known flow. Look at the graph on the left at 20 mA. Now you know that the fall in voltage of 1.85 V. Know that the voltage drop across the LED is not only a function of current, but also the color of the LED and the temperature (because of chemical differences in the LED).

Color Potential Difference (LED voltage)
  • Infrared : 1.6 V
  • Red : 1.8 V - 2.1 V
  • Orange : 2.2 V
  • Yellow : 2.4 V
  • Green : 2.6 V
  • Blue : 3.0 V - 3.5 V
  • White : 3.0 V - 3.5 V
  • Ultraviolet : 3.5 V
The following example circuit LED (Menentukan Nilai Resistor Pada LED) series / parallel based on Ohm's law, V = IR to refer to the list above the LED voltage

Led parallel
Resistor values = (voltage source - LED voltage) / LED current
  • Red LED resistor values (12 V- 1.8V) /0.02 A = 510 ohms
  • Blue LED resistor values (12V - 3V) / 0.02 A = 450 ohms
LED SeriResistor values = (voltage source - the total LED voltage) / LED current
  • Resistor values = (12V - 9.6 V) / 0.02 A = 120 ohms

Skema Rangkaian Elektronika