

			HANDY CARTRIDGE ENCRYPTION SYSTEM


	This disk contains the current system for encrypting a boot block for
a ROM file that will allow a cartridge to be made that will run on the Lynx.
The program that actually performs the RSA part of the encryption, and the
separate pieces of the RSA key number are not included on this disk.

	To use this disk, either copy its contents to a directory on a hard
disk, or insert it into a floppy drive and CD to it.  You will also need a
floppy disk with the volume name RSA;  if you don't have one, insert a blank
disk into drive 0 of your computer and type:
		FORMAT drive df0: name RSA
at the CLI prompt.  To encrypt a ROM file, type:
		EXECUTE DOIT <filename> <size>
at the CLI prompt, where <filename> is name of the ROM file to encrypt, and
size is one of 128, 256 or 512 specifying the size (in K) of the ROM file.
Then just follow directions as they are given on the screen.

	The source to the separate pieces of the process are also included on
this disk.  The following files are made from the corresponding source files:
		BUILDCHK - buildchk.c
		PREMOD	 - premod.c
		POSTMOD	 - postmod.c
		BUILDROM - main.c, buildrom.c, global.c, rombin.h, eglobal.c

	BUILDCHK is a program that scans the image file, locates the directory
entries for the first two files and writes the information to romdir.i , and
simulates the hash code security process performed in the boot block to
generate the check string and write it to checkstring.src .

	PREMOD takes a raw binary file, and prepares the data to be run
through the RSA encryption program.

	POSTMOD takes the output of the RSA encryption program, and prepares
it for inclusion in the boot block.

	BUILDROM takes the files boot.raw and boot2.raw (the results of the
encryption process) and writes them over the beginning of the ROM file.

	MAKEFILE contains directions to build the above C programs, assuming
an Aztec C environment.  The C programs assume 32 bit integers.

	The file boot.src assembles to create the code to be encrypted in the
boot blocks.  It includes the system equates files harddefs.i and cartdefs.i ,
and the generated files romsize.i, romdir.i, and checkstring.src .


