ESP 8266 -
All GPIO Pins extended with berg pins
3.3v Power Regulator on board.
RST pin pulled high through resistor.
CH_PD pin also pulled high through resistor.
Supply 5v can be safely provided at 5v / Gnd pins
TXD / RXD / GND pins can be connected with USB to TTL converter and AT commands can be tested using a serial monitor software like PUTTY or HERCULES
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