Question

What is the minimum no of cycles required for reset operation?

(a) 3 cycle

(b) 2 cycles

(c) 1 cycles

(d) 4 cycles

I had been asked this question during an online interview.

My question is from Microcontroller (8051- Pin, Registers, Timers) in section Prototyping Embedded Devices of IOT

Answer 1

Right choice is (c) 1 cycles

Explanation: When power is turned on, the circuit holds the RST pin high for an amount of time that depends on the capacitor value and the rate at which it changes. To ensure a valid reset the RST pin must be held high long enough to allow the oscillator to start up plus two machine cycles.