Merge pull request #543 from AkosLukacs/patch-2

ESP32 - added pins to docs that can be watched

Author: gfwilliams

boards/ESP32.md

@@ -501,7 +501,12 @@ There are 8 channel available. Each one with is connected to a pin. Timimg goes
 Implemented with the esp-idf RMT driver.
 
 ### setWatch implementation
-
+[These pins can be watched](https://github.com/espruino/Espruino/blob/8d193bab16a08d013dbb5689c9666b81039990a4/targets/esp32/jshardware.c#L473-L477):
+ * D0 
+ * D12 .. D19 
+ * D21, D22 
+ * D25 .. D27 
+ * D34 .. D39
 
 
 ---