I am following these connections given in this instructable.
http://www.instructables.com/id/Getting ... /?ALLSTEPS
VCC ----> 3.3V Power supply (Vout of LM1117)
GND ----> Ground of power supply
CH_PD ----> HIGH (3.3V)
GPIO2 ----> HIGH (3.3V)
GPIO15 ----> LOW (GND)
GPIO0 ----> HIGH or Floating for AT Mode (3.3V) [ * if you want to flash completely different firmware then you must connect it to ground ]
Any help is appreciated.
Thanks in advance