Michael Rigby-Jones wrote:

>>> It might do 40MHz, but it's rated as a 25MHz part along with
>>> the rest of this particular sub-family including the 6620,6720 and 8620.

The 18F6xxx and 18F8xxx range has both 25 and 40 Mhz parts. Check
the Line Card. Yes, you might find a "sub-sub-family" amongst
those that are rated at either 25Mhz or 40Mhz, but I read your post
as including all 18F6xxx and 18F8xxx parts.

>>> In fact even 25MHz is not reliably achievable on existing silicon, the
>>> errata states that 4MHz is the maximum clock frequency to avoid a bug
>>> that causes random corruption during the instruction fetch.

What "errata" ?

I have checked a three random errata sheets for the 18F6xxx and 18F8xxx
range, and can not find that problem in any of them.

Isn't the "4Mhz problem" an issue for the 18F1220 and friends ?

Jan-Erik.

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