960-999



     Wilkinson's "Insight: Atari" columns in COMPUTE!, November
     and December 1981, and in Microcomputing, August 1982. Also
     refer to the OS User's Manual and De Re Atari.

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960-999        3C0-3E7        PRNBUF
     Printer buffer. The printer handler collects output from LPRINT
     statements here, sending them to the printer when an End of Line
     (EOL; carriage return) occurs or when the buffer is full. Normally
     this is 40 characters. However, if an LPRINT statement generates
     fewer than 40 characters and ends with a semicolon or 38
     characters and ends with a comma, Atari sends the entire buffer
     on each FOR-NEXT loop, the extra bytes filled with zeros. The
     output of the next LPRINT statement will appear in column 41 of
     the same line. According to the Operating System User's
     Manual, the Atari supports an 80-column printer device called
     P2:. Using OPEN and PUT statements to P2: may solve this
     problem. Here is a small routine for a GR.0 BASIC screen dump:

     10  DIM TEXT$(1000): OPEN#2,4,0,"S:":
         TRAP 1050
     .
     .
     .
     1000  FOR LINE = 1 TO 24: POSITION PE
          EK(82),LINE
     1010  FOR COL = 1 TO 38: GET#2,CHAR:
          TEXT$(COL,COL)=CHR$(CHAR)
     1020  NEXT COL: GET#2,COL
     1030  LPRINT TEXT$
     1040  NEXT LINE
     1050  RETURN

     You can use the PTABW register at location 201 ($C9) to set the
     number of spaces between print elements separated by a comma.
     The minimum number of spaces accepted is two. LPRINT
     automatically uses channel seven for output. No OPEN statement
     is necessary and CLOSE is automatic.

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Locations 1000 to 1020 ($3E8 to $3FC) are a reserved spare buffer
area.

1021-1151      3FD-47F        CASBUF
     Cassette buffer. These locations are used by the cassette handler
     to read data from and write data to the program (tape) recorder.
     The 128 ($80) data bytes for each cassette record are stored
     beginning at 1024 ($400 - page four). The current buffer size is