You're both right and wrong.  The 16C84 uses EEPROM technology.  This makes
it erasable electrically, obviously.  The F84 parts use FLASH EPROM, making
it electrically erasable also.
The OTP parts use EPROM technology, but due to the fact that they're in a
solid plastic package,
they cannot be erased.  There's no way for the UV light to get to the array.
Hope this clears up your confusion.


Regards,


Jim

-----Original Message-----
From: Greg Wiley <greg@LOOP.COM>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Thursday, July 08, 1999 6:20 PM
Subject: Confusion on PIC part numbers


>I am confused by Microchip's device number assignment.
>
>In the mid-range PIC overview documentation, they
>claim that parts with Fs use EEPROM for program store,
>and that parts with Cs use EPROM for program store.
>
>Thus, my little brain says:  16F84 is electrically erasable
>and 16C84 is UV erasable or OTP, depending on the
>package.  They are probably similar in other respects.
>
>Well, I know that the F84 is electrically erasable.  It's
>the one I have been messing with.  But now I want a
>compatible part that is OTP so I pull up the spec sheet
>for the 16C84 and it says that the device uses elect-
>rically erasable program store.  The only difference wrt
>the F84 seems to be the amount of RAM.
>
>So, am I missing something?  Is there a OTP equivalent
>to the 16F84?
>
>TIA,
>
>  -greg