Alarm Digital Clock-DS1307

Posted on Feb 6, 2014

DS1307 is a hardware realtime clock, which works on I2C protocol. Better graphics using the same old fashioned alphanumeric LCD (type HD44780). Icons which shows the status for Alarm ON/OFF state, which gives a nice and cute look to the clock. Circuit diagram for the digital clock. 2x16 LCD is connected to the port 2 of AT89C51. P1. 0 of uC will pr

Alarm Digital Clock-DS1307
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ovide the SCL (serial clock) and P1. 1 SDA (serial data) for I2C communication. When the power supply is switched on it will give you the default date and time, but later you can change it to the desired value. After setting once, the backup battery will keep the clock ticking even after the power is not there. Acknowledgement-After sending of one byte of data the reciever has to acknowledge the sender for the successful reception. for this the sender make the SDA line high and reciever pulls down the SDA low, which tells the sender that data has reached safely. Now the source code written in assembly, basically implements the I2C protocol. the assembly source written for Keil. Download for Clock. asm and the Clock. hex file for programming the controller. Digital Clock Schematic is available in PDF format can be downloaded. For ppl who wants to edit the code but they dont have the A51 Macro assembler/Keil, they can use the following software to disassemble the hex file and change it according to their need. The disassembling software can be downloaded from following link:

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