we r using philips 89c669 ,in design we r using DS1232 to provide reset to 89C669. Reset doesnt come up most of the time.
Is this problem of microcontroller?
"Is this problem of microcontroller?"
Not usually.
The reset signal does not come up? So I'd ask myself: What device drives the reset signal; the MicroMonitor or the microcontroller?
Have you used the correct reset signal? The DS1232 has one open-drain active-low reset signal, and one push-pull active high signal.
Have you looked at the reset signal? Does it leave the reset state 250ms after power has reached correct values? Will the supply voltage ever reach correct values?