A:/eclipse/mhvlib/MHV_Display_HD44780_Direct_Connect.cpp

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/* Copyright (c) 2011, Make, Hack, Void Inc
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *  * Neither the name of the Make, Hack, Void nor the
 *    names of its contributors may be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL MAKE, HACK, VOID BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <util/delay.h>
#include <MHV_Display_HD44780_Direct_Connect.h>

#define HD44780_DB4                     (1 << _dataPin)
#define HD44780_DB5                     (1 << (_dataPin + 1))
#define HD44780_DB6                     (1 << (_dataPin + 2))
#define HD44780_DB7                     (1 << (_dataPin + 3))
#define HD44780_RS                      (1 << _controlPin)
#define HD44780_RW                      (1 << (_controlPin + 1))
#define HD44780_E                       (1 << (_controlPin + 2))
#define HD44780_CONTRAST        (1 << _visualPin)
#define HD44780_LED                     (1 << (_visualPin + 1))

/* Delay times in iterations of delay_loop_1 - note that each pass of delay_loop_1 is 3 clocks
 */
#define HD44780_TC              (1000 * 1000000 / F_CPU / 3 + 1)
#define HD44780_TSU1    (60 * 1000000 / F_CPU / 3 + 1)
#define HD44780_TSU2    (195 * 1000000 / F_CPU / 3 + 1)
#define HD44780_TDH             (5 * 1000000 / F_CPU / 3 + 1)
#define HD44780_TW              (450 * 1000000 / F_CPU / 3 + 1)
#define HD44780_TINIT   300             // ms
#define HD44780_TCLEAR  1530    // us
#define HD44780_TINSTR  39              // us
#define HD44780_TRAM    430             // us

MHV_Display_HD44780_Direct_Connect::MHV_Display_HD44780_Direct_Connect(
                MHV_DECLARE_PIN(data),
                MHV_DECLARE_PIN(control),
                MHV_DECLARE_PIN(visual),
                uint8_t colCount, uint16_t rowCount, MHV_RingBuffer &txBuffers) :
                MHV_Display_HD44780(colCount, rowCount, txBuffers) {
        _dataDir = dataDir;
        _dataOut = dataOut;
        _dataIn = dataIn;
        _dataPin = dataPin;
        _controlOut = controlOut;
        _controlPin = controlPin;
        _visualOut = visualOut;
        _visualPin = visualPin;

// Set pins as output
        _dataMask = 0x0f << _dataPin;
        *_dataDir |= _dataMask;
        *_dataOut &= ~(_dataMask);

        uint8_t mask = 0x07 << _controlPin;
        *controlDir |= mask;
        *_controlOut &= ~mask;

        mask = 0x03 << _visualPin;
        *visualDir |= mask;
        *_visualOut &= ~(mask);

        _brightness = 5;
        _contrast = 6;
}

MHV_Display_HD44780_Direct_Connect::MHV_Display_HD44780_Direct_Connect(
                MHV_DECLARE_PIN(data),
                MHV_DECLARE_PIN(control),
                uint8_t colCount, uint16_t rowCount, MHV_RingBuffer &txBuffers) :
                MHV_Display_HD44780(colCount, rowCount, txBuffers) {
        _dataDir = dataDir;
        _dataOut = dataOut;
        _dataIn = dataIn;
        _dataPin = dataPin;
        _controlOut = controlOut;
        _controlPin = controlPin;

// Set pins as output
        _dataMask = 0x0f << _dataPin;
        *_dataDir |= _dataMask;
        *_dataOut &= ~(_dataMask);

        uint8_t mask = 0x07 << _controlPin;
        *controlDir |= mask;
        *_controlOut &= ~mask;
}


void MHV_Display_HD44780_Direct_Connect::writeByte(uint8_t byte, bool rs) {
        // Write high order nibble
        writeNibble(byte >> 4, rs);
        // Write low order nibble
        writeNibble(byte & 0x0f, rs);
}

void MHV_Display_HD44780_Direct_Connect::writeNibble(uint8_t nibble, bool rs) {
        uint8_t oldPort = *_dataOut & ~(_dataMask);
        *_controlOut &= ~(HD44780_RW);
        if (rs) {
                *_controlOut |= HD44780_RS;
        }

        *_dataOut = oldPort | ((nibble << _dataPin) & _dataMask);

        _delay_loop_1(HD44780_TSU1);
        *_controlOut |= HD44780_E;
        _delay_loop_1(HD44780_TW);
        *_controlOut &= ~HD44780_E & ~HD44780_RS;
        _delay_loop_1(HD44780_TW);
}


uint8_t MHV_Display_HD44780_Direct_Connect::readByte(bool rs) {
        char character = readNibble(rs) << 4;
        // Read low order nibble
        character |= readNibble(rs);

        return character;
}

uint8_t MHV_Display_HD44780_Direct_Connect::readNibble(bool rs) {
        *_controlOut |= HD44780_RW;
        if (rs) {
                *_controlOut |= HD44780_RS;
        }

        *_dataDir &= ~_dataMask;
        _delay_loop_1(HD44780_TSU1);
        *_controlOut |= HD44780_E;
        _delay_loop_1(HD44780_TW);
        uint8_t data = *_dataIn;
        *_controlOut &= ~HD44780_E & ~HD44780_RS;
        *_dataDir |= _dataMask;
        _delay_loop_1(HD44780_TW);

        return data >> _dataPin;
}

bool MHV_Display_HD44780_Direct_Connect::isBusy() {
        *_dataDir &= ~(HD44780_DB7);
        *_dataOut &= ~(HD44780_DB7); // turn off pullup
        *_controlOut |= HD44780_RW;
        _delay_loop_1(HD44780_TSU1);
        *_controlOut |= HD44780_E;
        _delay_loop_1(HD44780_TW);

        bool busy = *_dataIn & HD44780_DB7;
        *_controlOut &= ~(HD44780_E | HD44780_RW);
        *_dataDir |= HD44780_DB7;

        _mustDelay = true;

        return busy;
}

void MHV_Display_HD44780_Direct_Connect::setBacklight(uint8_t value) {
        if (value > 15) {
                value = 15;
        }
        _brightness = value;
}

void MHV_Display_HD44780_Direct_Connect::setContrast(uint8_t value) {
        if (value > 15) {
                value = 15;
        }
        value = 15 - value;

        _contrast = value;
}

void MHV_Display_HD44780_Direct_Connect::tickPWM() {
        if (0 == _ticks % 16) {
                *_visualOut |= HD44780_LED;
                *_visualOut |= HD44780_CONTRAST;
        }

        if (_brightness == _ticks % 16) {
                *_visualOut &= ~HD44780_LED;
        }

        if (_contrast == _ticks % 16) {
                *_visualOut &= ~HD44780_CONTRAST;
        }

        _ticks++;
}

void MHV_Display_HD44780_Direct_Connect::delay(MHV_HD44780_COMMAND command) {
        return;
}

void MHV_Display_HD44780_Direct_Connect::init(bool multiLine, bool bigFont, bool cursorOn, bool cursorBlink,
                                bool left2right, bool scroll) {
        MHV_Display_HD44780::init(false, multiLine, bigFont, cursorOn, cursorBlink, left2right, scroll);
}