update:
- removed the 10 KHz test as TWBR is not valid for 10KHz as TWBR is a byte ..
- updated title of thread.
new 0.1.03 version: (replaces all earlier versions)
- removed 10 KHz
- added 800 KHz (my RTC DS3231 seems to work reliably on this speed)
- fixed TWBR math
- d: delay toggle => now only waits for 5 millis if device is found.
- added millis() time stamp in the output.
latest version of the code see first post