TextDisplay.h

00001 /* mbed TextDisplay Library Base Class
00002  * Copyright (c) 2007-2009 sford
00003  * Released under the MIT License: http://mbed.org/license/mit
00004  *
00005  * A common base class for Text displays
00006  * To port a new display, derive from this class and implement
00007  * the constructor (setup the display), character (put a character
00008  * at a location), rows and columns (number of rows/cols) functions.
00009  * Everything else (locate, printf, putc, cls) will come for free
00010  *
00011  * The model is the display will wrap at the right and bottom, so you can
00012  * keep writing and will always get valid characters. The location is 
00013  * maintained internally to the class to make this easy
00014  */
00015 
00016 #ifndef MBED_TEXTDISPLAY_H
00017 #define MBED_TEXTDISPLAY_H
00018 
00019 #include "mbed.h"
00020 #include "Stream.h"     // need on mbed-os-6.2.0, Aug. 5th, 2020 by JH1PJL
00021 
00022 /**
00023  * TextDisplay interface
00024  */
00025 class TextDisplay : public Stream {
00026 public:
00027 
00028     /**
00029      * Create a TextDisplay interface
00030      *
00031      * @param name The name used in the path to access the strean through the filesystem
00032      */
00033     TextDisplay(const char *name = NULL);
00034 
00035     /**
00036      * Output a character at the given position
00037      *
00038      * @param column column where charater must be written
00039      * @param  row where character must be written
00040      * @param c the character to be written to the TextDisplay
00041      */
00042     virtual void character(int column, int row, int c) = 0;
00043 
00044     /**
00045      * Return number of rows on TextDisplay
00046      *
00047      * @results number of rows
00048      */
00049     virtual int rows() = 0;
00050 
00051     /**
00052      * Return number if columns on TextDisplay\
00053      *
00054      * @results number of rows
00055      */
00056     virtual int columns() = 0;
00057     
00058     // functions that come for free, but can be overwritten
00059 
00060     /**
00061      * Redirect output from a stream (stoud, sterr) to  display
00062      *
00063      * @param stream stream that shall be redirected to the TextDisplay
00064      */
00065     virtual bool claim (FILE *stream);
00066 
00067     /**
00068      * Clear screen
00069      */
00070     virtual void cls();
00071     
00072     /**
00073      * Change the cursor position to column, row (in pixels)
00074      */
00075     virtual void locate(int column, int row);
00076     
00077     virtual void foreground(uint16_t colour);
00078     virtual void background(uint16_t colour);
00079     // putc (from Stream)
00080     // printf (from Stream)
00081     
00082 protected:
00083 
00084     virtual int _putc(int value);
00085     virtual int _getc();
00086 
00087     // character location
00088     uint16_t _column;
00089     uint16_t _row;
00090 
00091     // colours
00092     uint16_t _foreground;
00093     uint16_t _background;
00094     char *_path;
00095 };
00096 
00097 #endif