89S52 External Interrupts. Hi all... i am making a project for driving a dc motor clock and anticlock wise using L293D which is connected to port 3^3(pin 2 of L293D) and port3^4(Pin 7 of L293D) and 89s52, 20x4 character lcd, keypad, 7.4v li-ion battery. using 7805 to stepdown 7.4v to 5v which is futher applied to my circuit. at initial stage i have kept my lcd off, so as button 1 is pressed from keypad the lcd goes on and again waits for user input from keypad to drive dc motor clock or anticlock wise. but when i even put my lcd to off, my 89s52 is in active mode which consumes my battery. to solve this problem i want to add power down mode to my controller. so i added Code:
PCON |= 0x02; // Enter Power Down Mode count++; // External Interrupt or Reset Wakes-up MCU
to enter power down mode. but now i am not aware of how to exit power down mode as i am very new to electronics and programming. can anybody please help me with the code to exit Power down mode.
i want something like as if when button 1 is pressed to on the lcd, it should exit power down mode and lcd gets on.
thanks a lot... but sorry what is TCON and IE
read the documentation I gave you the links to
to be very frank with you.... the link you have provided me is quite difficult to understand. it reads something like 0003H or FFFFH and all like that.... i am not getting exactly what it mean...