Board generic (platform esp8266, package esp8266) is unknown, when using both 1.6.6 and 1.6.7 - so am going back to 1.6.5....a well.
Board generic (platform esp8266, package esp8266) is unknown, when using both 1.6.6 and 1.6.7 - so am going back to 1.6.5....a well.