>
>This is the point I was trying to make, too.  Here's a brief list of
>part-numbering inconsistencies and annoyances:

>
>3.  In most cases, an "A" designation after a part number (e.g.,
>16C73A) means only that some silicon bugs have been fixed, and that
>the chip is otherwise identical (except for some configuration-word
>details and a little extra reset circuitry, perhaps) to a "non-A"
>part.  However, there are other cases, like the 16C84A, where the
>part has been significantly enhanced -- by doubling the RAM size,
>for instance.

Further more, there are times a "A" suffix is not added when in fact the
part is an "A-TYPE" device. The 16C63 is one such case. The real importance
here is that everyone knows the 16Cxx "A" parts have uneraseable code protection
but not so the non "A" parts. But the 16C63 being an "A" suffix type without
the
"A" is a TRAP.

DON'T use the code protection on the 16C63-JW parts.

>
>4.  When the Microchip powers-that-be decide that an "A' designation
>is inappropriate for a part that's been enhanced like that, they
>sometimes rename the "non-A" part AND the "A" part (e.g, the 16C71
>and 16C71A became the 16C710 and 16C711), but in other cases, they
>just rename the "A" part (e.g., the 16C84 keeps its old name, but
>the 16C84A is now called the 16F84).
>

Actually Andy, I think you are wrong here. The 16C710 is NOT a renamed
16C71, it is a renamed 16C70. The 16C70 was an "A-TYPE" revision to begin
with without the "A" suffix (Like the 16C63.)  So here, there IS a little
method in the madness. (But strong emphasis on "little.")  As far as I know,
the 16C71 is still the 16C71.


>5.  As long as I'm talking about those two chips, how come the
>16C71/71A got extra digits, while the 16C84A only had its LETTER
>changed?  Why didn't Microchip rename the '84s "16(C/F)840" and
>"16(C/F)841"?

I know!!! (Me thinks I know at least!) It's because microchip have
decided that all 16Cxx parts with A/D will be generically 16C7x?.
The 16C710/711/715 are all of the same generic sub-branch. Without the
extra digit, not all the planned A/D devices could be included under the
16C7X? brand.

The 16C84A becames 16F84 as a misleading marketing tool. We all understand this
much....

Without the extra digit when the 16C84 has an generic overlap with the 16C71,
can we conclude the 16C8x family will not be as extensive as the 16C7x family?
>
>
>-Andy
>
It is not just the stuffing arround with the part numbers that are a pain.
The arbitrary "paper" changes to certain devices is also a REAL hazzard. The
latest device to suffer from this is the PIC14000. The Code protect scheme
is NOT the same as it was orginally specified. However ALL the current AP
notes,
and latest header files still are using the OLD specification.

Any programmer designed arround the new specification is gone to give different
results to the code protection!!! Further more, the user may not even know this
has happened! Does this concern anyone other than myself?

Jim