Re: Apple IIc Booting from external drive

[ddkilzer@iastate.edu (David D Kilzer)]

NOTE:  Someone along the line added "comp.sys.apple2.comm" to the
Newsgroups: line.  I have removed it since this topic is not relevant to
that group.

>kevins@donald.ee.pdx.edu (Kevin Stanton) writes:

>|> It says ''cannot read disk'' when trying to boot up.
>|> I tried pr#6,2 but it still spun up drive A.
>|> 
>|> Is there a way to bypass this?
>|> 
>I think that you can boot from the //c's external drive into ProDOS (only).


voss@i40s16.ira.uka.de (Stefan Voss) writes:

>Try this:
>1. go to BASIC.
>2. put a bootable ProDOS disk in the external drive.
>3. Do PR#7.

>Hope it works,

Only if you have a //c with original ROMs.  If you do a PRINT PEEK(64447) 
from a BASIC prompt and see the number 255 printed, then you have a
original ROM //c.  Here's the stuff from the //c Tech Note #7 about what
PR#7 does, along with some other information.  This document and all
other file-type and tech notes are available via anonymous FTP from
ftp.apple.com.

BTW, 64447=$FBBF for those who are hex-deficient.  ;^)

-=-=-=-=-=-
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
-=-=-=-=-=-

Dave
-- 
David D. Kilzer               \                ST:TNG _Relics_
Computer Engineer 3           /       Capt. Montgomery Scott ("Scotty")
ddkilzer@iastate.edu          \   "I may be a captain by rank, but I never
Iowa State University, Ames   /    wanted to be anything but an engineer."