Subject: Re: What's the difference between a IIc that is a "3" and a "4"?
From: dempson@actrix.gen.nz (David Empson)
Date: Sat, Nov 28, 1998 05Ç16+  
Message-id: <1dj9bb7.1ef58ip1qkv4q2N@dempson.actrix.gen.nz>

Jason Whorton <jason@microxl.com> wrote:

> Hello.  What is the difference between a IIc that reports "3" on the print
> peek (64447) and one that reports "4"?

The "3" version is the memory expansion IIc (the first one that contains
the memory expansion slot).  The "4" version has bug fixes but no new
features.

Here is the technical note which describes all the Apple IIc firmware
revisions (reformatted slightly).


Apple II
Technical Notes
________________________________________________________________________
                                             Developer Technical Support


Apple IIc
#7:    Existing Versions

Revised by:    Matt Deatherage                             November 1988
Written by:    Guillermo Ortiz                             November 1987

This Technical Note describes the main differences between the five
different IIc ROM versions which encompass the original IIc and four
revisions.
________________________________________________________________________


Original IIc ( $FBBF = $FF )

o    Can use the IIc external drive only
o    No AppleTalk firmware
o    PR#7 boots the second drive
o    Mouse firmware maps to slot 4
o    Serial firmware does not mask incoming linefeed characters
o    Serial firmware does not support XON/XOFF protocol


3.5 ROM IIc ( $FBBF = $00 )

o    Can use the IIc external drive and the UniDisk 3.5 drive
o    AppleTalk firmware maps to slot 7
o    PR#7 returns the message "AppleTalk Off Line"
o    Mouse firmware maps to slot 4
o    Serial firmware defaults to mask all incoming linefeed characters
o    Serial firmware supports XON/XOFF protocol

Original "Memory-Expandable" IIc ( $FBBF = $03 )

o    Can use the IIc external drive, the UniDisk 3.5 drive, and the IIc
     Memory Expansion Card
o    Mouse firmware maps to slot 7
o    No AppleTalk firmware
o    PR#7 kills the system
o    Serial firmware defaults to mask all incoming linefeed characters
o    Serial firmware supports XON/XOFF protocol


Revised "Memory-Expandable" IIc ( $FBBF = $04 )

Same as Original Memory-Expandable, plus:
o    Keyboard buffering firmware bug fixed
o    Firmware returns correct information when the Memory Expansion Card
     is not present


Apple IIc Plus ( $FBBF = $05 )

o    Can use the external IIc drive, the UniDisk 3.5 drive, the Apple
     3.5 drives, but not the original IIc Memory Expansion Card.
o    Contains a Memory Expansion Card connector
o    3.5" internal drive replaces 5.25" internal drive
o    Mouse maps to slot 7
o    PR#7 kills the system
o    4 MHz 65C02 microprocessor
o    Accelerator chip and static RAM cache permit operation up to 4 MHz
o    Keyboard replaced with Apple Standard Keyboard (minus numeric
     keypad)
o    Internal power supply
o    Internal modem connector
o    Serial ports refitted with mini-DIN 8 connectors
o    Headphone jack has been removed
o    Volume control relocated above the keyboard
o    40/80 column switch replaced by keyboard (Sholes/Dvorak) switch


Further Reference
o    Apple IIc Technical Reference Manual
o    Apple IIc Technical Note #5, Memory Expansion on the Apple IIc
o    Apple IIc Technical Note #6, Buffering Blues
o    Apple II Miscellaneous Technical Note #2, Apple II Family
     Identification Routines 2.1
o    Apple II Miscellaneous Technical Note #7, Apple II Family
     Identification
o    Apple II Miscellaneous Technical Note #8, Pascal 1.1 Firmware
     Protocol ID Bytes



-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand