Impulse #02 31 декабря 1997

Программирование

Programmers - Fast Decruncher to packer Data-Squeezer v4.x.

   Now proceed to the consideration of accelerated DECRUNCHERa 
to DSQ. To use it you

need to pack in DSQ
the file and write the uncompressed file on disk without
DECRUNCHERa by answering NO to the question "INCLUDE DECRUNCHER 
(Y / N)?". There you will be asked a few more

questions for which answers are not
have no value (bug
DSQ).


   Here it is necessary to stipulate a
moment, which can lead to
fatal consequences: the starting address of packed files
(ORG in the following program) should be several
bytes lower than address in which to unpack the original file.


   In DECRUNCHER (the first three
line) must be replaced
the following values:

 - In the first row (DATLEN) to record the length of the packed 
file, which you kept the DSQ. 

- The second (STRFIL) - start address of the original file
ie address to which you want
raspakovt file.

 - In the third line (ENDFIL) must enter a last byte of the 
source file, which is calculated by adding the starting address 
and length, minus 1. 



   Also, if necessary,
instead of the last command RET
You can put JP # xxxx for
Startup after unpacking.



   For example, to unpack the OSD files packed DSQ
2048 bytes, first line
you need to put 2048 in the second - 16384, and the third line -
16384 +6912-1 = # 5AFF (23,295).


   But, in fact, the text
most DECRUNCHERa:


DATLEN EQU 2048
STRFIL EQU 16384
ENDFIL EQU 23295


        ORG xx-nn; (!!!)
START LD DE, 16384

        LD HL, DECR

        PUSH DE

        LD BC, FL2-FL1

        LDIR

        LD DE, START

        LD HL, DATA

        LD BC, DATLEN

        RET
DECR
FL1 LDIR

        LD BC, 264

        EX DE, HL

        DEC HL

        EXX

        PUSH HL

        LD DE, ENDFIL
DR5 LD HL, 1

        EXX

        DJNZ DR20

        LD B, C

        LD E, (HL)

        DEC HL
DR20 RL E

        EXX

        JR NC, DR1

        LD B, L

        INC L

        EXX

        DJNZ DR21

        LD B, C

        LD E, (HL)

        DEC HL
DR21 RL E

        EXX

        JR C, DR6

        INC B

        LD L, 4

        EXX

        DJNZ DR22

        LD B, C

        LD E, (HL)

        DEC HL
DR22 RL E

        EXX

        JR C, DR6

        EXX

        DJNZ DR23

        LD B, C

        LD E, (HL)

        DEC HL
DR23 RL E

        EXX

        JR NC, DR7

        LD B, L

        XOR A
DR24 EXX

        DJNZ DR25

        LD B, C

        LD E, (HL)

        DEC HL
DR25 RL E

        EXX

        RLA

        DJNZ DR24

        ADD A, 8

        LD L, A

        CP 1923

        JR C, DR8

        LD B, 5

        XOR A
DR35 EXX

        DJNZ DR34

        LD B, C

        LD E, (HL)

        DEC HL
DR34 RL E

        EXX

        RLA

        DJNZ DR35

        ADD A, 14

        LD L, A
DR1 LD B, 8

        XOR A
DR26 EXX

        DJNZ DR27

        LD B, C

        LD E, (HL)

        DEC HL
DR27 RL E

        EXX

        RLA

        DJNZ DR26

        LD (DE), A

        DEC DE

        DEC L

        JR NZ, DR1

        JR DR9
HEDGE JR DR5
DR7 LD L, 1923
DR2 LD B, 8
DR6 XOR A

        LD C, A
DR29 EXX

        DJNZ DR28

        LD B, C

        LD E, (HL)

        DEC HL
DR28 RL E

        EXX

        RL C

        RLA

        DJNZ DR29

        LD B, A

        LD A, C

        ADD HL, BC

        INC A

        JR Z, DR2
DR8 PUSH HL

        LD HL, 33

        EXX

        DJNZ DR30

        LD B, C

        LD E, (HL)

        DEC HL
DR30 RL E

        EXX

        JR C, DR10

        LD B, 9

        ADD HL, DE

        EXX

        DJNZ DR31

        LD B, C

        LD E, (HL)

        DEC HL
DR31 RL E

        EXX

        JR NC, DR11

        LD B, 5

        LD L, E

        LD H, D

        INC HL

        JR DR11
DR10 LD B, 11

        LD H, 2

        ADD HL, DE
DR11 XOR A

        LD C, A
DR32 EXX

        DJNZ DR33

        LD B, C

        LD E, (HL)

        DEC HL
DR33 RL E

        EXX

        RL C

        RLA

        DJNZ DR32

        LD B, A

        LD A, C

        ADD HL, BC

        POP BC

        LDDR
DR9 LD HL, STRFIL-1

        SBC HL, DE

        JR C, HEDGE

        POP HL

        EXX

        RET
FL2
DATA INSERT "NAMEDATA"


   NAMEDATA - the name of the packed
a DSQ file recorded without
DECRUNCHERa.



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