I reach strange issue ...
I want to control AD9833 Waveform Generator with ESP8266 (ESP-210 module)
I found a good working code for that, created from Alexander C. Frank (http://www.changpuak.ch/electronics/AD9 ... erator.php)
it use 3 pins of ESP8266 with Wire.h library
it work very well with any combination of pins with two digits names ... 12, 13, 14, 15, 16 ...
but do not work if I try to use pins with single digit name: 0, 1, 2, 3, .....
not work mean ... the controller can not communicate with AD9833 (there is no any error in compilator ...)