Date   : Fri, 02 Dec 1983 11:45:00-PST
From   : ABN.ISCAMS@usc-isid
Subject: Re: Hexify for Tops-20

Keith (et al),

Correct, HEXIFY on Tops-20 doesn't seem to know how to peel off that
4-byte header from ITS-Binary files.  Someone on the net talked about a
TYPE8 program that peels that off, but that ain't much help when you're
dealing with a binary file you're trying to capture!

What I do (you're gonna love this) is HEXIFY the whole doggon thing,
first unwanted 4 bytes and all, and download it.  Invariably with a binary
.COM type file, it ends at a nice even hex boundary, as you'll see when you
load that .HEX file into DDT. 

Try this:  Run DDT (no file name).  Clear a whole bunch of TPA (at least
as big as your .HEX file will need) by filling it with 0's or F's
(F100,3000,00).  Load that .HEX file into DDT 
(IFOOBAR.HEX
 R)
Write down the NEXT available memory after the load.  (Hey, guys, hope
I'm not boring you with this pretty basic DDT stuff, but some out there
may need the walkthrough.)

Look at that area around the NEXT figure (use the D command), and you'll
see the binary code just barely spill over a 100 boundary -- 4 bytes,
to be precise!

Now move the whole  mess 4 bytes down!

M104,2004,100  (say FOOBAR.HEX ended at 2004H)

Look again, and you'll see a real program start at 100H (or wherever
your TPA starts), and a bunch of cryptic stuff (most programs seem to
lump a bunch of DB data stuff at the end) or maybe a nice neat JMP or
RET right at the 100H boundary (2000H for our example).

G0 to get out of DDT and SAVE 32 FOOBAR.COM (for our example; whatever
the appropriate SAVE is for your file).

If it ran in the original form, it'll run now!

Did this for a bunch of stuff; works just fine.  Have fun.

David Kirschbaum
Toad Hall