City #24 12 августа 1999

Программирование

Likbez - a full disassembler ROM (part 16).

   ************** **************** LIKBEZ


(C) P. Yu Fedin



    FULL DESCRIPTION + FULL ROM Disassembler


              TR-DOS 5.04T (5.03)


              For professionals


               And as for those


             WHO WANTS TO BE.



                    continued

Address 1921. Erasing files. Input: Set
23773, 23781, and search the file. Program
sets 23816 and 23815.
1921 XOR A; zeroing of the erased

                   Files

      LD (23815), A

      JR 1952, erasing files

Address 1927. Runs the command ERASE. Set
23825 and 23611.
1927 CALL 7647; receiving the file name on stack calcium
                   kulyatora

      CALL 7541; if there is a check in syntax

                   then return

      CALL 4142, receiving a file extension

      XOR A; yet nothing is erased

      LD (23815), A

      CALL 10543; installation and checkout the name of the STP
                   paradise file

      CALL 1952; erase file

      JP NZ, 1399, if the file is not erased at the end of ka
                   Taloga, then check how many

                   erased files

      JP 993; message O.K.

Address 1952. Erasing faylov.Vhod: Set 23773,
23781, reset 23815 and search the file.
The program installs 23,816 and 23,815.
1952 LD A, (23773), the preservation of the first character 
filename 

      LD (23816), A

      RET NZ; if the file was not found, the WHO
                    Gates

      LD HL, 23815; erased another file

      INC (HL)

      PUSH BC; saving the file number

      CALL 1021; read into the buffer sector 8 road
                    point 0

      LD A, (24073) take the number of files on the dis
                    Ke

      POP BC; restore the file number

      INC C; this file last?

      CP C

      JR NZ, 1980, if not, erasing the usual

                    order

      DEC A; to drive now on a smaller file
                    above

      LD (24073), A

      XOR A; erase the file in the catalog
1980 PUSH AF; saving feature of the method of the STP
                    Rania

      JR Z, 1987, if the file is not in the catalog,

      LD HL, 24089; then increase by 1 the number of

                    deleted files

      INC (HL)
1987 PUSH BC; retention rates erase

                    File

      CALL 7747; sector 8 dub track 0

      POP BC; recovery rates abrasion
                    On File

      DEC C

      CALL 5725; download the file descriptor

      POP AF; restoration of the flag of the method

                    erasure

      JP Z, 2002; if the file in the catalog, then

                    first character of name is CHR $ 0

      LD A, 1, otherwise it will be a CHR $
2002 LD (23773), A; installing the first character of name

      PUSH AF; preservation method erasure

      CALL 7744; record of the file descriptor

      LD A, (23816); restoring the first character

                    filename

      LD (23773), A

      POP AF; erasure recovery method

      JR Z, 2023, if the file is erased at the end of catalogs
                    ha, the reorganization of the descriptor

                    Disk

      CALL 7347; search for a file with the

                    name

      JR 1952; erase it if it is
2023 CALL 1021; reading sector 8 track 0

      LD HL, (23787), installation of a new beginning of freedom
                    Nogo place

      LD (24070), HL

      LD DE, (23786), setting a new number

                    free sectors

      LD HL, (24074)

      LD D, 0

      ADD HL, DE

      LD (24074), HL

      JP 7747; sector 8 dub track 0

                    and return

Address 2048. Positioning, with fast speed
moving the head. Put the physical number of tracks in the data 
register, and the team positioning - In the battery.

2048 AND 252; position with fast speed

      JP 15770; issuing commands and expecting INTRQ


             to be continued ...