atmel 89s51 -- how to demonstrate the inbuilt watchdog?

[saravanakumar09]

atmel 89s51

how to demonstrate the inbuilt watchdog timer in AT89s51 and please give assembly program for control the atmel microcontroller?

 

[IanP]

Re: atmel 89s51

To demonstrate the Watchdog in the 89S51 all what you have to do is to include the following sequence:

MOV 0A6h,#1Eh
MOV 0A6h,#0E1h

where 0A6h is the location of the WDTRST ..

and repeat it somewhere in your code so the processor is fed with it more often than, say, 15ms (Q=11,0592MHz), otherwise the “dog” will reset the uP every ≈ 16ms ..

All that is described in the AT89S51 data sheet ..


Rgds,
IanP

 

[saravanakumar09]

Re: atmel 89s51

respected sir,

we are trying to use watchdog timer in software mode at ATMEL 89S51 CHIP. we want example program for watchdog timer and please give information about how to use watch dog timer in atmel .
we are waiting for your reply .

thanking you sir.