Wolfram,

      I have not had any success in finding out whether you can or
      cannot use Ports C, D and E (and their associated direction
      registers) when in extended microcontroller mode.  I have a
      request in to the designer of the chip for an answer.  I did get
      one suggestion, however, if you really need more RAM you can use
      the PIC17C44 instead of the PIC17C42.

      I will let the list know when the answer comes in.

      Tchuess,

      Pete

      Pete Brink
      Senior Software Engineer
      Microchip Technology Inc.
      pete.brink@microchip.com


______________________________ Reply Separator _________________________________
Subject: Extended Microcontroller 17c42
Author:  Wolfram Liebchen <liebchen@IPSERV.FFO.FGAN.DE> at Internet_Exchange
Date:    4/26/96 4:05 AM


Does anybody know, what happens to the port C, D and E registers
and to the respective direction registers, when the PIC 17c4x is used
in extended microcontroller mode or in microprocessor mode?
Can I use them as general purpose registers or are they changed through
the accesses to external RAM / ROM?

TIA

Wolfram


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