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Author: SpenceKonde

avr/extras/UsingMicronucleus.md

@@ -38,7 +38,7 @@ The entry behavior of the included versions of Micronucleus does not always matc
 ### Clock Speed
 Micronucleus is built with a specific clock speed in mind; only a few are supported by the codebase, and generally the fastest that is an option is used: 12 MHz, 12.8 MHz, 15 MHz, 16 MHz, 16.5 MHz or 20 MHz. The 12.8 and 16.5 configurations are only used with the internal oscillator - and this extra speed gives the bootloader some room to correct for the lower clock accuracy. 16.5 is only possible on parts that can be clocked from an on-chip PLL (the ATtiny85 and ATtiny861 - though the internal oscillator on some (not all) ATtiny841 can reach those speeds as well - note that this is higher than the maximum spec for the chip, not just the internal oscillator!), and is within spec above 4.5v for those parts, while 12.8 MHz can be reached by the internal oscillator on other parts (although it is far outside spec for that). Where the internal oscillator is used, it is "tuned" to the needed frequency based on the USB clock.
 
-In the case of the ATtiny85, the internal oscillator is (by default) left at the 16.5 MHz setting so that USB will also work in the sketch. On the ATtiny84 and ATtiny841, this is not done; in the current version of ATTinyCore, USB cannot be used within the sketch on these parts. When running at 16.5 MHz, be aware that timing related code may be be less accurate - this has not been tested carefully, but I belive that millis() will be correct, but micros - and possibly delay - may not be)
+In the case of the ATtiny85, the internal oscillator is (by default) left at the 16.5 MHz setting so that USB will also work in the sketch. On the ATtiny84 and ATtiny841, this is not done; in the current version of ATTinyCore, USB cannot be used within the sketch on these parts. When running at 16.5 MHz, be aware that timing related code may be be less accurate - this has not been tested carefully, but I believe that millis() will be correct, but micros - and possibly delay - may not be)
 
 In order to support low-power operation, ATTinyCore provides an option to prescale the system clock on all Micronucleus boards (as well as most others) - as soon as the sketch starts, the oscillator will bw prescaled to run at the specified frequency. On the ATtiny85, an option for 12 MHz operation is also provided - this will reset `OSCCAL` to the factory setting