unit b_crt

OS independent screen and keyboard routines.

author: bocianu bocianu@gmail.com


Set of useful constants, registers and methods to cope with text input and output without ATARI OS.
This library is a part of 'blibs' - set of custom Mad-Pascal libraries.
https://gitlab.com/bocianu/blibs

Constants:

name:value:description:
CHAR_RETURN#$9bChars returned for special keys in ASCII code
CHAR_ESCAPE#$1b
CHAR_BACKSPACE#$7e
CHAR_TAB#$7f
CHAR_INVERSE#$81
CHAR_CAPS#$82
ICHAR_RETURN#219Chars returned for special keys in Antic code
ICHAR_ESCAPE#91
ICHAR_BACKSPACE#126
ICHAR_TAB#127
ICHAR_INVERSE#193
ICHAR_CAPS#194

Register Variables:

name:address:type:description:
kbcode$d209bytecode of last pressed key
consol$d01fbyteconsole keys status

Global Variables:

name:type:description:
CRT_vramwordcontains address of video memory
CRT_sizewordcontains size of video memory
CRT_screenWidthbytecontains width of screen in bytes
CRT_screenHeightbytecontains height of screen in bytes
CRT_cursorwordcontains cursor position in memory

Interface:

name:description:
CRT_Init

procedure CRT_Init(vram_address: word; width, height: byte); overload;


Initializes CRT library with video ram located at specified memory address, using custom values for screen width and height.
    parameters:
  • vram_address - memory address of video ram
  • width - width of the screen (chars)
  • height - height of the screen (rows)
CRT_Init

procedure CRT_Init(vram_address: word); overload;


Initializes CRT library with video ram located at specified memory address, Screen size is defined as default values (40 x 24).
    parameters:
  • vram_address - memory address of video ram
CRT_Init

procedure CRT_Init; overload;


Initializes CRT library with video ram pointed by savmsc register, Screen size is defined as default values (40 x 24).
    parameters:
  • vram_address - memory address of video ram
CRT_Clear

procedure CRT_Clear; overload;


Clears screen.
    CRT_Clear

    procedure CRT_Clear(filler: byte); overload;


    Clears screen using specified byte as filling value.
      CRT_ClearRow

      procedure CRT_ClearRow(row: byte); overload;


      Clears specified row of a screen.
        parameters:
      • row - number of row to clear
      CRT_ClearRow

      procedure CRT_ClearRow; overload;


      Clears current row of a screen.
        CRT_GotoXY

        procedure CRT_GotoXY(x, y: byte);


        Moves cursor to specified position on screen.
        x=0, y=0 is upper left corner.
          parameters:
        • x - cursor's horizontal position
        • y - cursor's vertical position
        CRT_WhereY

        function CRT_WhereY: byte;


        Returns current vertical position of cursor (row).
          returns:
        • (byte) - current row
        CRT_WhereX

        function CRT_WhereX: byte;


        Returns current horizontal position of cursor (column).
          returns:
        • (byte) - current column
        CRT_GetXY

        function CRT_GetXY(x, y: byte): byte;


        Returns byte located at specified position on screen.
        x=0, y=0 is upper left corner.
          parameters:
        • x - cursor's horizontal position
        • y - cursor's vertical position
          • returns:
        • (byte) - value at specified position
        CRT_Write

        procedure CRT_Write(s: string); overload;


        Outputs string at current cursor position.
        This function outputs text in Antic coding, not ATASCII. Add 'tilda' after finishing quote of your string to use Antic coding.
        Example: Write('Hello Atari'~);

        You may also use Atascii2Antic function, to convert strings.
          parameters:
        • s - string of text in Antic code
        CRT_Write

        procedure CRT_Write(num: integer); overload;


        Outputs integer value at current cursor position.
          parameters:
        • num - value to write.
        CRT_Write

        procedure CRT_Write(num: real); overload;


        Outputs real value at current cursor position.
          parameters:
        • num - value to write.
        CRT_WriteXY

        procedure CRT_WriteXY(x,y: byte; s: string);


        Outputs string at desired position of the screen.
        x=0, y=0 is upper left corner.
          parameters:
        • x - cursor's horizontal position
        • y - cursor's vertical position
        • s - string to output (in Antic code)
        CRT_WriteCentered

        procedure CRT_WriteCentered(row: byte; s:string); overload;


        Outputs centered string at specified row of the screen.
          parameters:
        • row - row number
        • s - string to output (in Antic code)
        CRT_WriteCentered

        procedure CRT_WriteCentered(s:string); overload;


        Outputs centered string in current row of cursor.
          parameters:
        • s - string to output (in Antic code)
        CRT_WriteRightAligned

        procedure CRT_WriteRightAligned(row: byte; s: string); overload;


        Outputs string right aligned at specified row of the screen.
          parameters:
        • row - row number
        • s - string to output (in Antic code)
        CRT_WriteRightAligned

        procedure CRT_WriteRightAligned(s: string); overload;


        Outputs string right aligned in current row of cursor.
          parameters:
        • s - string to output (in Antic code)
        CRT_Put

        procedure CRT_Put(b: byte); overload;


        Outputs single byte at current position of the cursor.
          parameters:
        • b - byte to be writen
        CRT_Put

        procedure CRT_Put(x, y, b: byte); overload;


        Outputs single byte at desired position of the screen.
        x=0, y=0 is upper left corner.
          parameters:
        • x - cursor's horizontal position
        • y - cursor's vertical position
        • b - byte to be writen
        CRT_KeyPressed

        function CRT_KeyPressed: boolean;


        Returns true if any key on keyboard is pressed down.
          returns:
        • (boolean) true if any key is down
        CRT_ReadKey

        function CRT_ReadKey: byte;


        Waits for key to be pressed and returns it's keyboard code.
          returns:
        • keyboard code of pressed key.
        CRT_ReadChar

        function CRT_ReadChar: byte;


        Waits for key to be pressed and returns it's value in ATASCII code.
          returns:
        • ATASCII code of pressed key.
        CRT_ReadCharI

        function CRT_ReadCharI: byte;


        Waits for key to be pressed and returns it's value in ANTIC code.
          returns:
        • ANTIC code of pressed key.
        CRT_ReadStringI

        function CRT_ReadStringI(limit: byte): string; overload;


        Reads string from keyboard, finished with return key, and returns it's value in ANTIC code.
        You can provide maximum number of chars to be entered.
          returns:
        • entered string in ANTIC code
        CRT_ReadStringI

        function CRT_ReadStringI: string; overload;


        Reads string from keyboard, finished with return key, and returns it's value in ANTIC code.
        Maximum length is 255 chars
          returns:
        • entered string in ANTIC code
        CRT_ReadString

        function CRT_ReadString(limit: byte): string; overload;


        Reads string from keyboard, finished with return key, and returns it's value in ATASCII code.
        You can provide maximum number of chars to be entered.
          returns:
        • entered string in ATASCII code
        CRT_ReadString

        function CRT_ReadString: string; overload;


        Reads string from keyboard, finished with return key, and returns it's value in ATASCII code.
        Maximum length is 255 chars
          returns:
        • entered string in ATASCII code
        CRT_ReadInt

        function CRT_ReadInt: integer;


        Reads integer value from keyboard, finished with return key,
          returns:
        • (integer) entered integer value
        CRT_ReadFloat

        function CRT_ReadFloat: real;


        Reads floating point value from keyboard, finished with return key,
        Dot symbol '.' is used to separate fractional part.
          returns:
        • (real) entered floating point value
        CRT_NewLine

        procedure CRT_NewLine; overload;


        Moves cursor to next line of screen.
          CRT_NewLine

          procedure CRT_NewLine(offset: byte); overload;


          Moves cursor to next line of screen and sets left margin (text offset).
            parameters:
          • offset - new value for left margin
          CRT_NewLines

          procedure CRT_NewLines(count: byte);


          Moves cursor down by specifien number of lines.
            parameters:
          • number of lines
          CRT_CarriageReturn

          procedure CRT_CarriageReturn;


          Moves cursor to the left margin of the screen,
            CRT_Invert

            procedure CRT_Invert(x, y, width: byte);


            Inverts part of the screen.
            x=0, y=0 is upper left corner.
              parameters:
            • x - starting cursor's horizontal position
            • y - starting cursor's vertical position
            • b - number of characters to be inverted
            CRT_InvertRow

            procedure CRT_InvertRow(row: byte);


            Inverts selected row of the screen.
              parameters:
            • row - row number to invert
            CRT_StartPressed

            function CRT_StartPressed: boolean;


            Returns true if START key is pressed down.
              returns:
            • (boolean) true if START key is down
            CRT_SelectPressed

            function CRT_SelectPressed: boolean;


            Returns true if SELECT key is pressed down.
              returns:
            • (boolean) true if SELECT key is down
            CRT_OptionPressed

            function CRT_OptionPressed: boolean;


            Returns true if OPTION key is pressed down.
              returns:
            • (boolean) true if OPTION key is down
            CRT_HelpPressed

            function CRT_HelpPressed:boolean;


            Returns true if HELP key is pressed down.
              returns:
            • (boolean) true if HELP key is down
            Atascii2Antic

            function Atascii2Antic(c: byte): byte;overload;


            Converts single byte from ATASCII to ANTIC coding.
              parameters:
            • c - byte to convert
            Antic2Atascii

            function Antic2Atascii(c: byte): byte; overload;


            Converts single byte from ANTIC to ATASCII coding.
              parameters:
            • c - byte to convert
            Atascii2Antic

            function Atascii2Antic(s: string): string; overload;


            Converts text string from ATASCII to ANTIC coding.
              parameters:
            • s - string to convert
            Antic2Atascii

            function Antic2Atascii(s: string): string; overload;


            Converts text string from ANTIC to ATASCII coding.
              parameters:
            • s - string to convert

            This documentation was generated using PasDoc.