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Showing posts from July, 2013

Alarm Clock without RTC using AT89C52

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     This clock works in 12 hour mode and is configured by programming the microcontroller  AT89C52 .  The program uses a delay function for producing a delay of 1 second.      On reset, the LCD prompts the user to set time. Only the hour and minute components can be set by pressing the corresponding switches, repeatedly. These switches are made active low and so they provide ground to the corresponding input pins of the controller. The AM/PM mode is set by toggling the switch between ground and Vcc. Ground would set the clock in AM mode while Vcc would set it in PM mode. The clock starts when start pin is connected to Vcc by pressing the switch.        The set time is displayed on LCD screen and changes as the time passes on. Seconds are increased after every one second by making use of delay function. As second reaches 59, minute is incremented by one and second is reset to 0. Similarly, as minute reache...

16X2 LCD and 8051 interfacing

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How to interface  16X2 LCD with 8051? Several electronic devices and projects require a message to be displayed in order to indicate their functioning. This topic explains how to display a message (string) on 16x2  LCD  by interfacing it to 8051 microcontroller ( AT89C52 ). LCD and AT89c52 interface