Once I have finished programming I need to disconnect EA from VCC so as to execute system code upon reset by watchdog.
No need, you need it at Vcc anyhow (!EA).

REMEMBER: NoTouch (and if developing "the backdoor") MUST be installed at first programming of the chip.


Erik

please suggest me one easily available in Indian market and where in Mumbai
Also any specific IC I can use?

contradictory statements