-// 2018-1-29 fork from let's split (#2308)
-// 2018-6-28 bug fix master to slave comm (#3255)
-// 2018-8-11 improvements (#3608)
-// 2018-10-21 fix serial and RGB animation conflict (#4191)
+// 2018-1-29 fork from let's split and add PD2, modify sync_recv() (#2308, bceffdefc)
+// 2018-6-28 bug fix master to slave comm and speed up (#3255, 1038bbef4)
+// (adjusted with avr-gcc 4.9.2)
+// 2018-7-13 remove USE_SERIAL_PD2 macro (#3374, f30d6dd78)
+// (adjusted with avr-gcc 4.9.2)
+// 2018-8-11 add support multi-type transaction (#3608, feb5e4aae)
+// (adjusted with avr-gcc 4.9.2)
+// 2018-10-21 fix serial and RGB animation conflict (#4191, 4665e4fff)
+// (adjusted with avr-gcc 7.3.0)
+// 2018-10-28 re-adjust compiler depend value of delay (#4269, 8517f8a66)
+// (adjusted with avr-gcc 5.4.0, 7.3.0)