RELOC.DOC  by James Yi/73327,1653


RELOC.BA is a program that will move a machine language routine to a different
address.
  First, LOADM the file to be moved( or the file may be in memory unsaved) to 
display its TOP,END,EXE addresses.  Then run the program.  Enter the file name,

and its TOP,END,EXE.  If there is a data table that is not to be interpreted as
  codes, then press 'y' to data table 
prompt and enter its starting and end addresses.  The program will skip this 
data table and not check it to see if it needs to be adjusted.  If you don't 
know if there is a data table, then just go with 'n'.  You have, perhaps, about
80% chance of success.Then enter the 
address to which it is to be moved.
    Choose Auto mode if you don't have a disassembly along with you and won't 
know what to answer to each prompt in Manual mode.  If run in Auto mode,it 
checks to see if any three-bytes-long-instruction points to an address within 
the range of the routine.  If it does, then the program pokes in a new value to

 adjust it to the new location.
    If auto mode didn't move the routine and adjust all addresses successfully,

you can try the Manual mode.  It will pause at each instruction that is 3 
bytes long.  Then a space bar will adjust its content, or any other key 
will leave it unchanged and pause at the next one.  One would probably need a 
source code to do this.  In most cases, auto mode will work.
    If neither mode has any success in relocating a machine language routine,
then it's probably one of the following:
  1) There's an indirect addressing scheme, where an HL pair is loaded in 
from a data table(the program skips data table), and the resulting HL content 
is
 pointing to a new address within the range of routine's Top and End 
addresses.
  2) A register pair such as HL is loaded seperately, therefore is not 
recognized as a three byte instruction by the program.
  3) The content of a three byte instruction such as JMP xx is poked in 
by the routine.  So when the program sees it, it might be JMP 0, and goes 
undetected, but after the routine is executed, its content may be changed to 
JMP 61000.


    As the program goes through and checks the routine, it displays at each 
line in order the following: the code's original location, new location in 
parenthesis, mnemonic or a number, if it is not a code but a data, its content 

if any, and the changed content in parenthesis, if it was changed.

After it's done, press 'y' to save the result, or any other key to cancel it.
Be sure that HIMEM is adjusted also.