Description: Apple IIGS: Recovering a corrupted ProFile
Header: Apple IIGS: Recovering a corrupted ProFile


 This article last reviewed: 29 March 1988

 In the Apple IIGS, the bus' higher 'noise' passes on to the ground traces
 on the ProFile interface card and, after use, corrupts the directory of the
 ProFile, rendering it invisible to ProDos and inaccessible to the user.

 It is possible to recover the directory and make the ProFile usable again. On
 the report of a ProFile going bad after installation in a Apple IIGS, first
 see the article "Apple II ProFile Interface Card Modification for the
 Apple IIGS.  This modification lets the card operate correctly for the
 directory fix. Don't try to repair a directory with an un-modified ProFile
 card.

 For the recovery, use a disk editor program, like the ProDos MLI Exerciser
 program here:

  1. Execute the ProDos Machine Language Interface Exerciser program with
     the '-' command and wait for the main menu.

  2. From the main menu, type '80'<Return> to command a read of a block;
     follow that by typing in the following values from the next screen:

        Parameter Count     $03 (Default)
        Unit Number         $50 (The ProFile card's slot followed by a '0')
        Data Buffer         $00 (This value is where the block to be modified
                            $40  will be loaded)
        Block Number        $02 (This is the bad block to load in)
                            $00

     After typing in each pair of numbers, press <Return> to go on to the
     next entry prompt. After pressing <Return> on the last entry, you see a
     message 'PRESS RETURN TO EXECUTE COMMAND', you press <Return> and then
     see another message 'Error $00: Call Successful'. At this point, press
     <Return> to get the main menu.

 3. Type 'M' <Return> to modify the buffer. The default should read:

                            $00
                            $40

     This is the correct setting; press <Return> on each entry and press it
     once more to go on to modify mode. At this point, you should see a table
     of numbers and a blinking cursor on the entry we want to 'delete', number
     '55'. Now that we know that problems with the directory exist, press
     <ESC> to go to the main menu.

     If the '55' was not in the first position of the table, then this
     directory recovery procedure won't work. If the '55' was not shown at
     all, your ProFile possibly has a different reason for not operating)

  4. Type '81' <Return> to write the block out to the disk. Press <Return>
     through the number entries until you reach the 'data buffer' entry.
     Change it to look like this:

                            $01
                            $40

     Continue to press <Return> through the block number entries and once
     more to command the actual block write, after which you will see the
     message 'Error $00: Call Successful' will be displayed.

  5. You may now reboot your system and check to see if the ProFile is now
     recognized. All of the data previously inaccessible should be back and
     usable.

 For more information about using the ProDOS Exerciser Program, see the
 ProDOS Technical Reference manual.
 Copyright 1988 Apple Computer, Inc.
 Keywords:  hts