File content as of revision 15:9323fab1db01:

/** Library for Holtek HT1632 LED driver chip,
 * As implemented on the Sure Electronics DE-DP10X and DE-DP13X1X display boards
 * 8 x 32 dot matrix LED module.)
 *
 * Original code by:
 * Nov, 2008 by Bill Westfield ("WestfW")
 *   Copyrighted and distributed under the terms of the Berkely license
 *   (copy freely, but include this notice of original author.)
 *
 * Adapted for 8x32 display by FlorinC.
 *
 * Arduino Library Created and updated by Andrew Lindsay October/November 2009
 *
 * Ported to Mbed platform by Andrew Lindsay, November 2012
 *
 * @author Andrew Lindsay
 *
 * @section LICENSE
 *
 * Copyright (c) 2012 Andrew Lindsay (andrew [at] thiseldo [dot] co [dot] uk)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:

 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @section DESCRIPTION
 *  Functions to drive displays
 *
 */

#include "mbed.h"
#include "HT1632_LedMatrix.h"
#include "font_5x7_p.h"

#define HIGH 1
#define LOW 0
/*
 * Set these constants to the values of the pins connected to the SureElectronics Module
 * For mbed, use WR=p7, DATA=p5, cs1=p17, cs2=p18, cs3=p19, cs4=p20
 */

// CS pins 17, 18, 19, 20 used.
// Stripboard
//DigitalOut  _cs[4] = {p17, p18, p19, p20};    // Chip Select (1, 2, 3, 4)
// PCB
DigitalOut *_cs[4]; // = { NC,NC,NC,NC};  //= {
//p19, p17, p18, p20};    // Chip Select (1, 2, 3, 4)

// helper macros
#define chip_number(x,y) (x >> 5) + (y >> 3)*numYDevices
#define chip_nibble_address(x,y) ((x%32)<<1) + ((y%8)>>2);
#define chip_byte_address(x,y) ((x%32)<<1);
#define max(a, b)  (((a) > (b)) ? (a) : (b))

// Display size and configuration, defaul is for a single 8x32 display
uint8_t numDevices = 1;    // Total number of devices
uint8_t numXDevices = 1;   // Number of horizontal devices
uint8_t numYDevices = 1;   // Number of vertical devices
uint8_t xMax = 32 * numXDevices-1;
uint8_t yMax = 8 * numYDevices-1;
uint8_t displayWidth = 32;
uint8_t displayHeight = 8;

// Variables used to keep track of cursor position
int cursorX = 0;
int cursorY = 0;

/*
 * we keep a copy of the display controller contents so that we can
 * know which bits are on without having to (slowly) read the device.
 */
// 4 boards at 32 bytes per board + 1 byte means we don't need to check overwrite in putChar
uint8_t shadowram[256];  // our copy of the display's RAM


// Custom character buffers - 8 characters available
// 6 cols * 8 rows - first byte of each char is the number of columns used
// Bits are aranged in columns with LSB at top
uint8_t cgram [8][7] = {
    { 0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
    { 0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
    { 0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
    { 0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
    { 0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
    { 0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
    { 0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
    { 0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
};


// Default constructor p19, p17, p18, p20
//HT1632_LedMatrix::HT1632_LedMatrix( void ) { }

HT1632_LedMatrix::HT1632_LedMatrix( PinName _clk, PinName _dat, PinName cs1, PinName cs2, PinName cs3, PinName cs4 ) :
    _wrclk(_clk), _data(_dat), _cs1(cs1), _cs2(cs2), _cs3(cs3), _cs4(cs4)
{
    _cs[0] = &_cs1;
    _cs[1] = &_cs2;
    _cs[2] = &_cs3;
    _cs[3] = &_cs4;
}

void HT1632_LedMatrix::init( uint8_t xDevices, uint8_t yDevices, uint8_t displayType )
{

    // Set up the display size based on number of devices both horizontal and vertical

    numXDevices = xDevices;
    numYDevices = yDevices;
    numDevices = numXDevices * numYDevices;

    if( displayType == HT1632_16x24 ) {
        displayWidth = 24;
        displayHeight = 16;
    } else {
        displayWidth = 32;
        displayHeight = 8;
    }
    xMax = displayWidth * numXDevices-1;
    yMax = displayHeight * numYDevices-1;

    // Disable all display CS lines by taking high
    for( uint8_t i = 0; i < 4; i++ )
        *_cs[i] = HIGH;

    for (uint8_t chipno=0; chipno<4; chipno++) {
        chipfree(chipno);     // unselect it

        sendcmd(chipno, HT1632_CMD_SYSON);    // System on
        sendcmd(chipno, HT1632_CMD_LEDON);    // LEDs on
        sendcmd(chipno, HT1632_CMD_BLOFF);    // Blink Off
        sendcmd(chipno, HT1632_CMD_MSTMD);    // Master Mode
        sendcmd(chipno, HT1632_CMD_RCCLK);    // Internal Oscillator
        if( displayType == HT1632_16x24 ) {
// TODO - check
            sendcmd(chipno, HT1632_CMD_COMS10);  // 16*24, NMOS drivers
        } else {
            sendcmd(chipno, HT1632_CMD_COMS00);  // 08*32, NMOS drivers
        }
        sendcmd(chipno, HT1632_CMD_PWM | 0x0c);   // PWM Duty

        for (uint8_t i=0; i<96; i++)
            senddata(chipno, i, 0);  // clear the display
        wait(0.1);
    }
    cursorX = 0;
    cursorY = 0;

}

void HT1632_LedMatrix::displayOff( void )
{
    for (uint8_t chipno=0; chipno<4; chipno++) {
        chipfree(chipno);     // unselect it
        sendcmd(chipno, HT1632_CMD_LEDOFF);    // LEDs on
    }
}

void HT1632_LedMatrix::displayOn( void )
{
    for (uint8_t chipno=0; chipno<4; chipno++) {
        chipfree(chipno);     // unselect it
        sendcmd(chipno, HT1632_CMD_LEDON);    // LEDs on
    }
}


/***********************************************************************
 * chipselect / chipfree
 * Select or de-select a particular ht1632 chip.
 * De-selecting a chip ends the commands being sent to a chip.
 * CD pins are active-low; writing 0 to the pin selects the chip.
 ***********************************************************************/
void HT1632_LedMatrix::chipselect(uint8_t chipno)
{
    *_cs[chipno] = LOW;
}

void HT1632_LedMatrix::chipfree(uint8_t chipno)
{
    *_cs[chipno] = HIGH;
}

/**
 * writebits
 * Write bits to HT1632 on pins HT1632_DATA, HT1632_WRCLK
 * Chip is assumed to already be chip-selected
 * Bits are shifted out from MSB to LSB, with the first bit sent
 * being (bits & firstbit), shifted till firsbit is zero.
 */
void HT1632_LedMatrix::writebits (uint8_t bits, uint8_t firstbit)
{
    while (firstbit) {
        _wrclk = LOW;
//        for( int i=0; i<2; i++);
        if (bits & firstbit) {
            _data = HIGH;
        } else {
            _data = LOW;
        }
        _wrclk = HIGH;
        firstbit >>= 1;
    }
}

/*
 * writedatabits
 * Write databits to HT1632 on pins HT1632_DATA, HT1632_WRCLK
 * Chip is assumed to already be chip-selected
 * Bits are shifted out from LSB to MSB
 */
void HT1632_LedMatrix::writedatabits (uint8_t bits, uint8_t count)
{
    while (count) {
        _wrclk = LOW;
//        for( int i=0; i<2; i++);
        _data = bits & 1;
        _wrclk = HIGH;
        count--;
        bits >>= 1;
    }
}

/*
 * sendcmd
 * Send a command to the ht1632 chip.
 * A command consists of a 3-bit "CMD" ID, an 8bit command, and
 * one "don't care bit".
 *   Select 1 0 0 c7 c6 c5 c4 c3 c2 c1 c0 xx Free
 */
void HT1632_LedMatrix::sendcmd (uint8_t chipno, uint8_t command)
{
    chipselect(chipno);  // Select chip
    writebits(HT1632_ID_CMD, 0x04);   // send 3 bits of id: COMMMAND
    writebits(command, 0x80);         // send the actual command
    writebits(0, 1);  // one extra dont-care bit in commands.
    chipfree(chipno); //done
}

/*
 * clear
 * clear the display, and the shadow memory, and the snapshot
 * memory.  This uses the "write multiple words" capability of
 * the chipset by writing all 96 words of memory without raising
 * the chipselect signal.
 */
void HT1632_LedMatrix::clear()
{
    char i;

    for (uint8_t chipno=0; chipno<numDevices; chipno++) {
        chipselect(chipno);  // Select chip
        writebits(HT1632_ID_WR, 0x04);   // send ID: WRITE to RAM
        writebits(0, 0x40);              // Send address
        for (i = 0; i < displayWidth; i++)         // Clear entire display
            writedatabits(0, 8);         // send 8 bits of data
        chipfree(chipno); // done
        for (i=0; i < 64; i++)
            shadowram[i+64*chipno] = 0;
    }
    cursorX = 0;
    cursorY = 0;
}


// Brighness is from 0 to 15
void HT1632_LedMatrix::setBrightness( unsigned char brightness )
{
    for (uint8_t chipno=0; chipno<numDevices; chipno++) {
        sendcmd(chipno, HT1632_CMD_PWM | (brightness & 0x0F ));
    }
}


/*
 * senddata
 * send a nibble (4 bits) of data to a particular memory location of the
 * ht1632.  The command has 3 bit ID, 7 bits of address, and 4 bits of data.
 *    Select 1 0 1 A6 A5 A4 A3 A2 A1 A0 D0 D1 D2 D3 Free
 * Note that the address is sent MSB first, while the data is sent LSB first!
 * This means that somewhere a bit reversal will have to be done to get
 * zero-based addressing of words and dots within words.
 */
void HT1632_LedMatrix::senddata (uint8_t chipno, uint8_t address, uint8_t data)
{
    chipselect(chipno);  // Select chip
    writebits(HT1632_ID_WR, 0x04);     // send ID: WRITE to RAM
    writebits(address, 0x40);          // Send address
    writedatabits(data, 4);            // send 4 bits of data
    chipfree(chipno); // done
}

/*
 * sendcol
 * send a byte of data to a particular memory location of the
 * ht1632.  The command has 3 bit ID, 7 bits of address, and 8 bits of data.
 *    Select 1 0 1 A6 A5 A4 A3 A2 A1 A0 D0 D1 D2 D3 D4 D5 D6 D7 D8 Free
 * Note that the address is sent MSB first, while the data is sent LSB first!
 * This means that somewhere a bit reversal will have to be done to get
 * zero-based addressing of words and dots within words.
 */
void HT1632_LedMatrix::sendcol (uint8_t chipno, uint8_t address, uint8_t data)
{
    chipselect(chipno);  // Select chip
    writebits(HT1632_ID_WR, 0x04);         // send ID: WRITE to RAM
    writebits(address, 0x40);              // Send address
    writedatabits(data, 8);                // send 8 bits of data
    chipfree(chipno); // done
}

// Write a string at the position specified
// x and y start from 0 and count number of pixels, 2nd row on a 2 row display is y=8
void HT1632_LedMatrix::putString(int x, int y, char *str)
{
    cursorX = x;
    cursorY = y;
    while( *str ) {
        putChar( cursorX, y, *str++ );
    }
}

/*
 * Copy a character glyph from the font data structure to
 * display memory, with its upper left at the given coordinate
 * This is unoptimized and simply uses plot() to draw each dot.
 */
void HT1632_LedMatrix::write( uint8_t c)
{
    putChar( cursorX, cursorY, (char)c );
}

/*
 * Copy a character glyph from the font data structure to
 * display memory, with its upper left at the given coordinate
 * This is unoptimized and simply uses plot() to draw each dot.
 * returns number of columns that didn't fit
 */
uint8_t HT1632_LedMatrix::putChar(int x, int y, char c)
{
    // fonts defined for ascii 32 and beyond (index 0 in font array is ascii 32);
    // CGRAM characters are in range 0 to 15 with 8-15 being repeat of 0-7
    // note we force y to be modulo 8 - we do not support writing character to partial y values.

    uint8_t charIndex;
    uint8_t colData;
    uint8_t numCols;
    uint8_t chipno;
    uint8_t addr;
    uint8_t colsLeft = 0;        // cols that didn't fit

    if( c > 15 ) {
        // Regular characters
        // replace undisplayable characters with blank;
        if (c < 32 || c > 126) {
            charIndex = 0;
        } else {
            charIndex = c - 32;
        }

        // move character definition, pixel by pixel, onto the display;
        // fonts are defined as one byte per col;
        numCols=smallFont[charIndex][6];   // get the number of columns this character uses
        for (uint8_t col=0; col<numCols; col++) {
            colData = smallFont[charIndex][col];
            chipno = chip_number(x,y);
            addr = chip_byte_address(x,y); // compute which memory byte this is in
            if (x <= xMax && y <= yMax) {
                shadowram[(addr>>1) + displayWidth * chipno] = colData;
                sendcol(chipno,addr,colData);
                x++;
            } else {
                colsLeft++;
            }
        }
    } else {
        // CGRAM Characters
        charIndex = c & 0x07;       // Only low 3 bits count
        numCols=cgram[charIndex][0];    // get the number of columns this character uses
        // fonts are defined as one byte per col;
        for (uint8_t col=1; col<=numCols; col++) {
            colData = cgram[charIndex][col];
            chipno = chip_number(x,y);
            addr = chip_byte_address(x,y); // compute which memory byte this is in
            if (x <= xMax && y <= yMax) {
                shadowram[(addr>>1) + displayWidth * chipno] = colData;
                sendcol(chipno,addr,colData);
                x++;
            } else {
                colsLeft++;
            }
        }
    }

    cursorX = x;
    cursorY = y;

    return colsLeft;
}

int  HT1632_LedMatrix::_putc(int c)
{
    if (c == '\n') {
        cursorY += 8;
        cursorX = 0;
    } else if (c == '\r') {
        // skip em
    } else {
        putChar(cursorX, cursorY, c);
        cursorX += 6;
//  if (wrap && (cursorX > (_width - 6))) {
//    cursorY += 8;
//    cursorX = 0;
//  }
    }

    return c;
}
int HT1632_LedMatrix::_getc()
{
    return -1;
}

// Set position of cursor for writing
void HT1632_LedMatrix::gotoXY(int x, int y)
{
    cursorX = x;
    cursorY = y;
}

void HT1632_LedMatrix::getXY(int* x, int* y)
{
    *x = cursorX;
    *y = cursorY;
}

void HT1632_LedMatrix::getXYMax(int* x, int* y)
{
    *x = xMax;
    *y = yMax;
}

// Shift cursor X position a number of positions either left or right.
void HT1632_LedMatrix::shiftCursorX(int xinc)
{
    cursorX += xinc;
}


/*
 * plot a point on the display, with the upper left hand corner
 * being (0,0), and the lower right hand corner being (xMax-1, yMax-1).
 * Note that Y increases going "downward" in contrast with most
 * mathematical coordiate systems, but in common with many displays
 * basic bounds checking used.
 */
void HT1632_LedMatrix::plot (int x, int y, char val)
{
    if (x<0 || x>xMax || y<0 || y>yMax)
        return;

    uint8_t chipno = chip_number(x,y);
    char addr = chip_byte_address(x,y); // compute which memory word this is in
    char shadowAddress = addr >>1;

    char bitval = 1<<(y&7);  // compute which bit will need set

    if (val) {  // Modify the shadow memory
        shadowram[shadowAddress + displayWidth * chipno] |= bitval;
    } else {
        shadowram[shadowAddress + displayWidth * chipno] &= ~bitval;
    }
    // Now copy the new memory value to the display
    sendcol(chipno, addr, shadowram[shadowAddress + displayWidth * chipno]);
}


void HT1632_LedMatrix::setCustomChar( int charNum, unsigned char cgchar[] )
{
    for(int i=1; i<7; i++ ) {
        cgram[charNum][i] = (uint8_t)cgchar[i];
    }
    cgram[charNum][6] = 0;
    cgram[charNum][0] = 6;
}

void HT1632_LedMatrix::setCustomChar( int charNum, unsigned char cgchar[], uint8_t numCols )
{
    numCols = max(numCols, 6 );
    for(int i=1; i<=numCols; i++ ) {
        cgram[charNum][i] = (uint8_t)cgchar[i];
    }
    cgram[charNum][0] = numCols;
    cgram[charNum][numCols] = 0;
}

void HT1632_LedMatrix::scrollLeft(uint8_t numberCols, uint8_t lineNum )
{
    for (int i=0; i<xMax-numberCols; i++) {
        shadowram[i]=shadowram[i+numberCols];
    }
    for (int i=xMax-numberCols; i<xMax; i++) {
        shadowram[i]=0;
    }

    cursorX -= numberCols;
    if (cursorX < 0 ) cursorX = 0;
}

void HT1632_LedMatrix::putShadowRam()
{
    for (int chipno=0; chipno<numDevices; chipno++)
        putShadowRam(chipno);
}

void HT1632_LedMatrix::putShadowRam(uint8_t chipno)
{
    for (int i=0; i<64; i+=2) {
        sendcol(chipno,i,shadowram[(i>>1)+ displayWidth * chipno]);
    }
}

#ifdef USE_GRAPHIC
/*
 * Name         : drawLine
 * Description  : Draws a line between two points on the display.
 * Argument(s)  : x1, y1 - Absolute pixel coordinates for line origin.
 *                x2, y2 - Absolute pixel coordinates for line end.
 *                c - either PIXEL_ON, PIXEL_OFF
 * Return value : none
 */
void HT1632_LedMatrix::drawLine(unsigned char x1, unsigned char y1,
                                unsigned char x2, unsigned char y2, unsigned char c)
{
    int dx, dy, stepx, stepy, fraction;

    /* Calculate differential form */
    /* dy   y2 - y1 */
    /* -- = ------- */
    /* dx   x2 - x1 */

    /* Take differences */
    dy = y2 - y1;
    dx = x2 - x1;

    /* dy is negative */
    if ( dy < 0 ) {
        dy    = -dy;
        stepy = -1;
    } else {
        stepy = 1;
    }

    /* dx is negative */
    if ( dx < 0 ) {
        dx    = -dx;
        stepx = -1;
    } else {
        stepx = 1;
    }

    dx <<= 1;
    dy <<= 1;

    /* Draw initial position */
    plot( x1, y1, c );

    /* Draw next positions until end */
    if ( dx > dy ) {
        /* Take fraction */
        fraction = dy - ( dx >> 1);
        while ( x1 != x2 ) {
            if ( fraction >= 0 ) {
                y1 += stepy;
                fraction -= dx;
            }
            x1 += stepx;
            fraction += dy;

            /* Draw calculated point */
            plot( x1, y1, c );
        }
    } else {
        /* Take fraction */
        fraction = dx - ( dy >> 1);
        while ( y1 != y2 ) {
            if ( fraction >= 0 ) {
                x1 += stepx;
                fraction -= dy;
            }
            y1 += stepy;
            fraction += dx;

            /* Draw calculated point */
            plot( x1, y1, c );
        }
    }
}


/*
 * Name         : drawRectangle
 * Description  : Draw a rectangle given to top left and bottom right points
 * Argument(s)  : x1, y1 - Absolute pixel coordinates for top left corner
 *                x2, y2 - Absolute pixel coordinates for bottom right corner
 *                c - either PIXEL_ON, PIXEL_OFF
 * Return value : none
 */
void HT1632_LedMatrix::drawRectangle(unsigned char x1, unsigned char y1,
                                     unsigned char x2, unsigned char y2, unsigned char c)
{
    drawLine( x1, y1, x2, y1, c );
    drawLine( x1, y1, x1, y2, c );
    drawLine( x1, y2, x2, y2, c );
    drawLine( x2, y1, x2, y2, c );
}


/*
 * Name         : drawFilledRectangle
 * Description  : Draw a filled rectangle given to top left and bottom right points
 *        just simply draws horizontal lines where the rectangle would be
 * Argument(s)  : x1, y1 - Absolute pixel coordinates for top left corner
 *                x2, y2 - Absolute pixel coordinates for bottom right corner
 *                c - either PIXEL_ON, PIXEL_OFF
 * Return value : none
 */
void HT1632_LedMatrix::drawFilledRectangle(unsigned char x1, unsigned char y1,
        unsigned char x2, unsigned char y2, unsigned char c)
{
    for(int i=y1; i <= y2; i++ ) {
        drawLine( x1, i, x2, i, c );
    }
}


/*
 * Name         : drawCircle
 * Description  : Draw a circle using Bresenham's algorithm.
 *        Some small circles will look like squares!!
 * Argument(s)  : xc, yc - Centre of circle
 *        r - Radius
 *        c - either PIXEL_ON, PIXEL_OFF
 * Return value : None
 */
void HT1632_LedMatrix::drawCircle(unsigned char xc, unsigned char yc,
                                  unsigned char r, unsigned char c)
{
    int x=0;
    int y=r;
    int p=3-(2*r);

    plot( xc+x,yc-y, c);

    for(x=0; x<=y; x++) {
        if (p<0) {
            y=y;
            p=(p+(4*x)+6);
        } else {
            y=y-1;
            p=p+((4*(x-y)+10));
        }

        plot(xc+x,yc-y, c);
        plot(xc-x,yc-y, c);
        plot(xc+x,yc+y, c);
        plot(xc-x,yc+y, c);
        plot(xc+y,yc-x, c);
        plot(xc-y,yc-x, c);
        plot(xc+y,yc+x, c);
        plot(xc-y,yc+x, c);
    }
}
#endif

// The end!