Thanks for the reply and the tip regarding bit position vs. pin number.
Indeed, this works for the counter-clockwise configuration:
int blinkPin = 4;
and this works for the clockwise configuration:
int blinkPin = 6;
I revisited the readme file and the spec sheet. I'm still having trouble grasping a couple of things.
The readme explains
Note that analog pin numbers (ex A0 ) cannot be used with digitalWrite()/digitalRead()/analogWrite() - all pins have a digital pin number. Analog pin number should only be used for analogRead().
However, I'm not clear on what the digital pin numbers are. Would that be the ones marked as "Arduino Pin" numbers? If so, the diagram defines the Arduino Pin number for port pin PA6 as:
"4/A6" for Alternate Pinout (which I now know is counter-clockwise, like ATTinyCore, and the default)
"6/A6" for standard(?) Pinout (which would be clockwise, like damellis)
Does this mean I can use either 4 or A6 for counter-clockwise orientation? I tried 4 and it works. I tried A6 and it did not work. Or, does this mean something different (like 4 for pin numbers and A6 for bit numbers, or 4 is digital and A6 is analog, ... ?). Any help here would be great so I can use the proper notation in my programs.
Additionally, I'm still a little confused about the clockwise vs counter-clockwise capability. Since I was using the ATTinyCore "package" in Arduino, and the ATTinyCore option was selected by default, I thought this was the correct thing to use.
This question is probably too basic for me to search it properly, but under what circumstance would I want to use the alternate pin mappings? Since the are default, I'm guessing they are maybe the 'recommended' setting for using the ATTinyCore. However, it is a little confusing that they don't align with the ATTiny84 spec sheet. So I'm assuming there is a good reason to deviate but I'm having trouble understanding what it is. I saw a blurb somewhere that it was related to ADC, but it hasn't clicked for me yet.
Thanks again!
Bill