C02/doc/stdiox.txt

Extended Input/Output Functions for C02 Programs

At the beginning of the program use the directives

  #include <stdlib.h02>
  #include <stdiox.h02>
  
The following functions are defined:

  putdec(b);          Writes the decimal representation of byte b to the
                      screen. The output will be between one and three 
                      digits with no leading spaces.
                      
                      Note: Calls part of the ctoa() routine from stdlib
                      which leaves the binary values of the ones, tens,
                      and hundreds digits in variables temp0, temp1, and 
                      temp2, respectively.

  putdel(b);          Writes the decimal representation of byte b to the
                      screen. The output is left justified by appending it 
                      with 1 space if b is between 10 and 99, or two spaces
                      if b is less than 10.
                      
                      Note: Calls putdec() and putspc(). Leaves the value
                      of b in varible temp3.

  putder(b);          Writes the decimal representation of byte b to the
                      screen. The output is right justified by prepending it
                      with 1 space if b is between 10 and 99, or two spaces
                      if b is less than 10.
                      
                      Note: Calls putdec() and putspc(). Leaves the value
                      of b in varible temp3.

  putdst();           Prints the destination string set by the setdst() or
                      setstr() functions. 
                      
                      This can be used to print the results of any function
                      call that stores it's result in the destination string,
                      such as strcat(), strcpy(), and strcut() in string,

                      Note: calls putc() and is called by printf() when
                      processing a %S formatting tag.
                      
  putspc(b);          Writes a space character to the screen. 

                      Note: Used by the putdel() and putder() functions.

  r = printf(b, &s):  Writes the value of byte b to screen, formatting
                      the output according the contents of string s. 
                      
                      The output consists of the characters in s, but with
                      any formatting tags replaced with an ASCII 
                      representation of the value of b.
                      
                      The recognized formatting tags are:
                      %C - output the ASCII character represented by b
                      %D - output b as a an unjustified decimal number
                      %H - output b as a two-digit hexadecimal number
                      %L - output b as a left justified decimal number
                      %R - output b as a right justified decimal number
                      %% - output a single % character
                      
                      Unlike the printf() function in standard C, only
                      one value argument may be passed and that value is
                      used for each formatting tag in the format string.
                      
                      One additional formatting tag is supported:
                      %S - output the destination string 
                      
                      The destination string is set using the setdst() or
                      strdst() functions (from the "string" library) before
                      calling printf(). Multiple occurances of the %S tag
                      will cause the destination string to be repeated.
                      
                      When tag types are mixed, the %S tag will output the
                      destination string, while the other tags will output
                      the formatted byte. If only the %S tag is used, then
                      the byte argument may be excluded from the call.

                      The letter in the formatting tag may be upper or 
                      lower case with either a 0 or 1 in the high bit.
                      Unrecognized formatting tags are interpreted as %C.
                      
                      Note: Calls putdec(), putdel(), putder(), prbyte(), or
                      putdst() depending on which formatting tags are used. 
                      The value of b is left in variable temp3.

Note: This library expects the following functions to be defined:

  cubcd();          Convert byte to BCD and unpack into three bytes
  prbyte();         Print byte to screen as hexadecimal number
  prchr(c);         Print ASCII character to screen
  setsrc(&s);       Set source string pointer and initialize index

along with the zero page variable pairs:
  
  srclo,srchi:      Source string pointer

and the temporary variables

  temp0,temp1,temp2,temp3