City #08 31 марта 1999

Программирование

Likbez - full description + full disassembler ROM (part 4).

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                     LIKBEZ
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(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



                   Data Files


  Disk operating system supports
with another type of files - data files. Files
data can be consistent and arbitrary
access. These files are divided into blocks of 16 sectors
with the same name. To work with these files
serve the following commands:

  1. Opening a file for sequential access
record.
OPEN # <thread number>, <filename> W []

  If you opened the file already exists, the data
will be appended to the end fayla.Posle, you can enter in your 
data file by displaying them in stream. For example:

PRINT # 4; "THIS IS A TEST LINE"

  Trying to use the stream for input will lead to
error
INVALID I / O DEVICE.

  2. Opening a file for sequential access
reading.
OPEN # <thread number>, <filename> R []

  Now you can enter data from a file through
stream, for example:
INPUT # 4; A $
 But bring something to a file you can not.

  3. Opening a file random access.
OPEN # <thread number>, <filename> RND, <record length>
[]
 Now you can access a file as input,
and for output. When you access a file, first output record 
number in a row, ending with its symbol CHR $ 6. Here you can 
enter or output data. After graduating from the input or output

CHR $ 13 must again show a record number. For example:
PRINT # 4, 0, "OUTPUT DATA"
INPUT # 4, (0), A $
PRINT # 4, 1, "RECORD 1"

  4. Close the file.

  After working with the file it should be closed. This
done through the command:
CLOSE # <thread id> []

  When working with the data file is created an additional 
channel. Its structure you see in the table below: 

Number of bytes in length content


     0 2 Address sub output

                  file (15630)

     February 2 Address sub decommissioning

                  File (15622)

     May 4 Not used

     September 1 is always equal to 36

     October 1 is always 1

     Nov. 1 No. drive, which at
                  must file

     12 January of the current block number in file

                  Directory

     February 13 length traversed part of the file

                  sequential access, and

                  as a relative address those
                  kuschego symbol for podprog
                  FRAMEWORK input from a file

     January 15 File Type:

                       0 - Serial to

                           reading

                     127 - Random Access

                    otherwise - to the serial

                    record

     August 16 Name of the current block file

     January 24 Expansion of the current block file

     25 January of the current block number in file

     January 26 is always equal to 32

     February 27 The length of the recorded portion of the 
current 

                  in bytes

     29 January of the current block length in sectors

                  (Always equal to 16)

     30 January number of the first sector of the current

                  file block

     31 January number of the first tracks on the current

                  file block

     32 1 The record length for file an
                  of free access

     33 1 A relative address for the symbol

                  for the sub output for pa
                  paper with a file to an arbitrary
                  mortar

     34 1 If 0, then the subroutine output

                  will host a record number,

                  otherwise the data. Only for file

                  random access.

     35 1 If not 0, then zag
                  manual ultrasonic sector next file

                  current will be rewritten

     36,256 Current sector file



  Attention! In all the routines for working with data files 
contains errors. 


             Working with sector files


  In the TR-DOS is also the opportunity to work directly
with sector files. For this purpose there are two teams.

  1. Reading the sector file.
PEEK <file name>,   []

  2. Record sector file.
POKE <file name>,   []
There are also teams PEEK <ENTER> and POKE <ENTER>,
which also act as LOAD <ENTER>.


              to be continued ...