Microcontroller 8051 with PC interface

yes i did dat also only buzzer nt wrkng properly switch wrking properly
N Thnx alot Majoka n Ricky World Team

hi Maherbaloch
buzzer need more current as compare to other things
use pull up resistor of 1 k on that pin where buzzer connected
using transistor to drive buzzer

hi majoka i have made dat on wireboard it iz wrkng excpt buzzer
thnx alot majoka and Ricky World Team

welcome Maherbaloch

now how does buzzer wrk i have used resistance and transister but still nt wrkng

hi Maherbaloch
ru check buzzer with out controller logic simple give it power is it beep or not
normally transistor not give as much power to it to beep u can use power transistor
can u post ur schematic how u use buzzer

hi Shashank1

could you say the importance of 8051 interrupt

interrupts are very necessary for any controller
in fact controller is nothing without interrupts
interrupt is used in multitasking applications
controller can execute one line at a time so when u need multiple tasks then we has to use interrupts
there are six interrupts in 8051
1) reset interrupt :
it is not controllable by software it is hardware interrupt
2) timer 0 interrupt
3) timer 1 interrupt
4) serial interrupt
5) external 0 interrupt
6) external 1 interrupt
these are all controllable by software