Compiler shows as ESP8266EX WiFi 26MHz 4MB Flash.
After test it seems that command pinmode(PBH, OUTPUT); corrupts the working of the serial monitor. It is pin D0 = GPIO16 = connected to the onboard LED close to the USB connector. This is a little bit annoying as I use it as a visual check during development, but then I also need the serial monitor for debugging as well. A limitation for this great product.