Reflow chapter 7 paragraphs

ch07.txt

@@ -1,38 +1,22 @@
 # CHAPTER 7 - CUSTOMIZING DOS
 
-Although DOS usually provides most of
-the functionality needed by the BASIC
-or assembly language programmer, at
-times a custom change is required.
-Making changes to your copy of DOS
-should only be undertaken when
-absolutely necessary, since new
-versions of DOS are released from
-time to time, and the job of moving
-several patches to a new version of
-DOS every few months can become a
-burden. In addition, wholesale
-modification of DOS without a clear
-understanding of the full
-implications of each change can
-result in an unreliable system.
+Although DOS usually provides most of the functionality needed by the BASIC or
+assembly language programmer, at times a custom change is required.  Making
+changes to your copy of DOS should only be undertaken when absolutely necessary,
+since new versions of DOS are released from time to time, and the job of moving
+several patches to a new version of DOS every few months can become a burden. In
+addition, wholesale modification of DOS without a clear understanding of the
+full implications of each change can result in an unreliable system.
 
 SLAVE VS MASTER PATCHING
 
-The usual procedure for making
-changes to DOS involves "patching"
-the object or machine language code
-in DOS. Once a desired change is
-identified, a few instructions are
-stored over other instructions within
-DOS to modify the program. There are
-three levels at which changes to DOS
-may be applied.
+The usual procedure for making changes to DOS involves "patching" the object or
+machine language code in DOS. Once a desired change is identified, a few
+instructions are stored over other instructions within DOS to modify the
+program. There are three levels at which changes to DOS may be applied.
 
-1 - A patch can be made to the DOS
-in memory. If this is done, a later
-reboot will cause the change to "fall
-out" or be removed.
+1 - A patch can be made to the DOS in memory. If this is done, a later reboot
+will cause the change to "fall out" or be removed.
 
 2 - A patch of the first type can be made permanent by initializing a diskette
 while running the patched DOS.  This procedure creates a slave diskette with a
@@ -41,16 +25,11 @@ newly created diskette is booted the patched version of DOS will be loaded.
 Also, any slave diskettes created by that diskette will also contain the patched
 version of DOS.
 
-3 - The patch is applied directly to
-a master diskette. This is somewhat
-more complicated. Either the patch
-may be made to the image of DOS on
-the first three tracks of a master
-diskette using a zap program, or
-MASTER CREATE may be used to write
-the changed copy of DOS to a new
-diskette. The following procedure may
-be followed to do this:
+3 - The patch is applied directly to a master diskette. This is somewhat more
+complicated. Either the patch may be made to the image of DOS on the first three
+tracks of a master diskette using a zap program, or MASTER CREATE may be used to
+write the changed copy of DOS to a new diskette. The following procedure may be
+followed to do this:
 
     BLOAD MASTER CREATE
     Get into the monitor (CALL -151)
@@ -67,95 +46,54 @@ be followed to do this:
     Complete the MASTER CREATE update normally. The
        resulting diskette will have the patches applied.
 
-This procedure will work for versions 3.2, 3.2.1, and 3.3 of
-DOS.
+This procedure will work for versions 3.2, 3.2.1, and 3.3 of DOS.
 
 AVOIDING RELOAD OF LANGUAGE CARD
 
-A rather annoying addition to DOS 3.3
-was a patch to the Boot 2 code to
-store a binary zero in the first byte
-of the Language Card, forcing DOS to
-reload BASIC (either INTEGER or
-APPLESOFT) for every boot, whether or
-not the machine was just powered up.
-When the machine is first powered up
-this patch is not necessary, since
-the first byte of the Language Card
-does not appear to DOS to be either
-BASIC, and it will reload the card
-anyway. On subsequent reboots, more
-often than not, a good copy of BASIC
-already resides in the Language Card
-and this patch results in a LANGUAGE
-NOT AVAILABLE error message after
-booting a slave diskette. Presumably
-the patch was added for version 3.3
-to allow for the eventual possibility
-that a language like PASCAL whose
-first byte of code just happens to
-match one of the BASICs would cause
-strange results in DOS. If the user
-always powers the machine off and on
-between using DOS and any other
-system, the patch may be removed as
-follows.
+A rather annoying addition to DOS 3.3 was a patch to the Boot 2 code to store a
+binary zero in the first byte of the Language Card, forcing DOS to reload BASIC
+(either INTEGER or APPLESOFT) for every boot, whether or not the machine was
+just powered up.  When the machine is first powered up this patch is not
+necessary, since the first byte of the Language Card does not appear to DOS to
+be either BASIC, and it will reload the card anyway. On subsequent reboots, more
+often than not, a good copy of BASIC already resides in the Language Card and
+this patch results in a LANGUAGE NOT AVAILABLE error message after booting a
+slave diskette. Presumably the patch was added for version 3.3 to allow for the
+eventual possibility that a language like PASCAL whose first byte of code just
+happens to match one of the BASICs would cause strange results in DOS. If the
+user always powers the machine off and on between using DOS and any other
+system, the patch may be removed as follows.
 
-At $BFD3 (48K) is a STA instruction which
-stores a zero on the Language Card.
-This instruction must be made into
-three no-operation instructions:
+At $BFD3 (48K) is a STA instruction which stores a zero on the Language Card.
+This instruction must be made into three no-operation instructions:
         BFD3:EA EA EA
 
-A slave diskette may then be INITed
-using this modified version of DOS
-and that diskette will have the
-patch in its DOS. The address of the
-store instruction for a 32K DOS is
-7FD3 and for a 16K DOS is 3FD3.
+A slave diskette may then be INITed using this modified version of DOS and that
+diskette will have the patch in its DOS. The address of the store instruction
+for a 32K DOS is 7FD3 and for a 16K DOS is 3FD3.
 
 INSERTING A PROGRAM BETWEEN DOS AND ITS BUFFERS
 
-Once in a while it is useful to find
-a "safe" place to load a machine
-language program (a printer driver,
-perhaps) where BASIC and DOS
-can never walk over it, even if DOS
-is coldstarted. If the program is
-less than 200 bytes long, $300 is a
-good choice. For larger programs,
-it is usually better to "tuck" the
-program in between DOS and its
-buffers (assuming the program is
-relocatable and will run at that
-location). To do this, load the
-program into low RAM, copy it to high
-RAM right below $9D00 (for a 48K
-machine), over the top of DOS's
-buffers, change the first buffer
-address at $9D00 to point below your
-program, (remember to allow 38 extra
-bytes for the filename and link fields)
-and JMP to $3D3 (DOS
-COLDSTART). This will cause DOS to
-rebuild its buffers below your
-program and "forget" about the memory
-your program occupies until the next
-time DOS is booted. Of course, BASIC
-can not get at that memory either,
-since its HIMEM is below the DOS
-buffers.
+Once in a while it is useful to find a "safe" place to load a machine language
+program (a printer driver, perhaps) where BASIC and DOS can never walk over it,
+even if DOS is coldstarted. If the program is less than 200 bytes long, $300 is
+a good choice. For larger programs, it is usually better to "tuck" the program
+in between DOS and its buffers (assuming the program is relocatable and will run
+at that location). To do this, load the program into low RAM, copy it to high
+RAM right below $9D00 (for a 48K machine), over the top of DOS's buffers, change
+the first buffer address at $9D00 to point below your program, (remember to
+allow 38 extra bytes for the filename and link fields) and JMP to $3D3 (DOS
+COLDSTART). This will cause DOS to rebuild its buffers below your program and
+"forget" about the memory your program occupies until the next time DOS is
+booted. Of course, BASIC can not get at that memory either, since its HIMEM is
+below the DOS buffers.
 
 BRUN OR EXEC THE HELLO FILE
 
-Ordinarily, when DOS finishes booting
-into memory, it performs a RUN
-command on the HELLO file in its file
-name buffer (left there by the INIT
-command which wrote DOS to the
-diskette).  To change the RUN command
-to a BRUN or an EXEC, apply the
-following patch to DOS (48K):
+Ordinarily, when DOS finishes booting into memory, it performs a RUN command on
+the HELLO file in its file name buffer (left there by the INIT command which
+wrote DOS to the diskette).  To change the RUN command to a BRUN or an EXEC,
+apply the following patch to DOS (48K):
 
      9E42:34         (for BRUN)
      ..or..
@@ -163,15 +101,10 @@ following patch to DOS (48K):
 
 REMOVING THE PAUSE DURING A LONG CATALOG
 
-Normally, when a CATALOG command is
-done on a disk with many files, DOS
-will pause every time the screen
-fills with names to allow the user
-time to see them all.
-By pressing any key
-the CATALOG continues.  If this pause
-is undesirable, apply the following
-patch to DOS (48K):
+Normally, when a CATALOG command is done on a disk with many files, DOS will
+pause every time the screen fills with names to allow the user time to see them
+all.  By pressing any key the CATALOG continues.  If this pause is undesirable,
+apply the following patch to DOS (48K):
 
      AE34:60