/members-area/personalblogs/b/blog/posts/atmega-attiny-microcontroller-programming-shield-for-arduino-as-isp-r2---5This will be the last posting about R2. 1. Limitations of R2 and the ideas for the enhancement. a. R2 doesn’t support ATtiny with external clock.I decided not to make R2 support ATtiny with external clock because I don’t use this combinatio...en-USTelligent Community 12