Category : Unprotects for Games and Such
Archive   : UNPROT2.ZIP
Filename : VISICALC.UNP

[[This patch was extracted from the PHOENIX IBM-PC Software
Library newsletter. They received it from the HAL-PC users group of
Houston, TX. Corrected by Jack Wright. Many thanks to them.]]

**** CONVERT VISICALC TO A .COM FILE ****

USE THE FOLLOWING PROCEDURE TO TRANSFER THE 80-COLUMN VISICALC PROGRAM
FROM THE VISICALC DISK AND WRITE A STANDARD .COM FILE WHICH MAY BE
LOADED ON A NON-STANDARD DISK DRIVE (WINCHESTER, 8", ETC).

FORMAT A DISK AS FOLLOWS: (FORMAT B:/S(ENTER)).
START THE DEBUG SYSTEM.
INSERT THE VISICALC DISK IN DRIVE A:
THEN TYPE:

-L 100 0 138 2 (LOAD THE VC80 LOAD/DECRYPTER)
-M 0 3FF 7000 (DUPLICATE IT IN HIGHER MEMORY)
-R CS (INSPECT COMMAND SEGMENT REGISTER)

DEBUG WILL RESPOND WITH THE CONTENTS OF THE CS REGISTER (eg. 04B5) AND
PROMPT WITH A COLON (:). TYPE THE OLD CONTENTS + 700 (HEX). (eg. 04B5
BECOMES 0BB5). DO THE SAME WITH THE 'DS' REGISTER.
DEBUG response to R CS might be:

CS 04B5 <-Save the value you get, we'll need it later.
:0BB5 <-Type in your CS value + 700hex here
-R DS <-Type
DS 04B5
:0BB5 <-Type in your DS value + 700hex here

NEXT:
Take the low order byte of the CS you saved above and substitute it
for LL in the next line. Substitute the high order byte for HH:

-E 107 LL HH (ENTER BYTE-FLIPPED CS) Ex: -E 107 B5 04
-E 24D BB A8 00 90 (HARD-WIRE THE DECRYPTION KEY)

NOW, WE MUST RUN THE LOADER/DECRYPTER, TYPE:

-G =1B8 26B (EXECUTE FROM 1B8 TO 26B)

THE ENTIRE PROGRAM WILL NOW BE LOADED AND DECRYPTED AND A REGISTER DUMP
SHOULD APPEAR ON THE SCREEN. NOW RESTORE CS AND DS TO THEIR PREVIOUS
VALUES AND SET THE FILE LENGTH IN CX. Set BX=0:

-R CS
CS 0BB5 <-Yours might be different
:04B5 <-Type in the value of CS you saved above
-R DS
DS 0BB5
:04B5 <-Type in the value of DS you saved above
-R BX
BX F3FD
:0
-R CX
CX 0000
:6B64 (LENGTH = 6B64 FOR VERSION 1.1, 6802 FOR VERSION 1.0)

NOW WE MUST NAME THE FILE, WRITE IT AND EXIT.
REMOVE THE VISICALC DISK FROM A:
INSERT THE NEW, FORMATTED, EMPTY DISK IN A:
TYPE:

-N VC.COM (OR WHATEVER YOU WISH TO NAME IT)
-W (WRITE THE .COM FILE)
-Q (EXIT FROM DEBUG)
***YOU ARE DONE*****
Back in DOS, type VC to try it.