GSM BASED DIGITAL NOTICE BOARD
INTRODUCTION
The user sends a SMS containing the data to be rolled.
PC receives the SMS and send it to both the slaves via RS232 -RS485 converter section.
Both the slaves receive the frame. Then they match the slave ID in the frame to their own ID’s.
If ID match occurs then that particular slave rolls the data on it’s alphanumeric display.
GSM BASED DIGITAL NOTICE BOARD
BLOCK DIAGRAM
COMPONENTS USED
Microcontroller PIC( 16F877A).
RS 232 and 485 Transreceivers.
Octal Bus Transreceivers (74LS245).
Alphanumeric
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