was SCI delay needed?

[nerdralph]

https://github.com/wagiminator/ATtiny84-TinyCalibrator/blob/main/software/TinyCalibrator_v0.5.ino#L327

The datasheet says the minimum clock period is 220ns. I had no problems with a period of 250ns (cbi + sbi instructions on a 16MHz AVR), so I'd think that you certainly wouldn't need the delay on a t84 running at 12MHz.

[wagiminator]

Oh yes, you are right. I forgot that cbi and sbi each need two clock cycles ;-) I'll change that in the next version.