RIOT/boards/chronos/drivers/display.c

/**
 *
 *  Copyright (C) 2009 Texas Instruments Incorporated - http://www.ti.com/
 *
 *
 *    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 Texas Instruments Incorporated 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 THE COPYRIGHT
 *    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

/**
 * @ingroup chronos
 * @{
 */

/**
 * @file
 * @brief   eZ430-chronos display driver
 *
 * @author  Oliver Hahm <oliver.hahm@inria.fr>
 * @author  Ludwig Knüpfer <ludwig.knuepfer@fu-berlin.de>
 * @author  Kaspar Schleiser <kaspar@schleiser.de>
 * @author  mikoff
 *
 */

#include <string.h>
#include <cc430f6137.h>

#include "display.h"

void write_lcd_mem(uint8_t *lcdmem, uint8_t bits, uint8_t bitmask, uint8_t state);
void clear_line(uint8_t line);
void display_symbol(uint8_t symbol, uint8_t mode);

/** Display flags */
volatile s_display_flags_t display;

/** Global return string for itoa function */
char itoa_str[8];

void lcd_init(void)
{
    /* Clear entire display memory */
    LCDBMEMCTL |= LCDCLRBM + LCDCLRM;

    /* LCD_FREQ = ACLK/16/8 = 256Hz */
    /* Frame frequency = 256Hz/4 = 64Hz, LCD mux 4, LCD on */
    LCDBCTL0 = (LCDDIV0 + LCDDIV1 + LCDDIV2 + LCDDIV3) | (LCDPRE0 + LCDPRE1) | LCD4MUX | LCDON;

    /* LCB_BLK_FREQ = ACLK/8/4096 = 1Hz */
    LCDBBLKCTL = LCDBLKPRE0 | LCDBLKPRE1 | LCDBLKDIV0 | LCDBLKDIV1 | LCDBLKDIV2 | LCDBLKMOD0;

    /* I/O to COM outputs */
    P5SEL |= (BIT5 | BIT6 | BIT7);
    P5DIR |= (BIT5 | BIT6 | BIT7);

    /* Activate LCD output */
    LCDBPCTL0 = 0xFFFF; /* Select LCD segments S0-S15 */
    LCDBPCTL1 = 0x00FF; /* Select LCD segments S16-S22 */

#ifdef USE_LCD_CHARGE_PUMP
    /* Charge pump voltage generated internally, internal bias (V2-V4) generation */
    LCDBVCTL = LCDCPEN | VLCD_2_72;
#endif
}

void clear_display_all(void)
{
    // Clear generic content
    clear_line(LINE1);
    clear_line(LINE2);
}

void clear_display(void)
{
    clear_line(LINE1);
    clear_line(LINE2);
}

void clear_line(uint8_t line)
{
    display_chars(switch_seg(line, LCD_SEG_L1_3_0, LCD_SEG_L2_5_0), NULL, SEG_OFF);

    if (line == LINE1) {
        display_symbol(LCD_SEG_L1_DP1, SEG_OFF);
        display_symbol(LCD_SEG_L1_DP0, SEG_OFF);
        display_symbol(LCD_SEG_L1_COL, SEG_OFF);
    }
    /* line == LINE2 */
    else {
        display_symbol(LCD_SEG_L2_DP, SEG_OFF);
        display_symbol(LCD_SEG_L2_COL1, SEG_OFF);
        display_symbol(LCD_SEG_L2_COL0, SEG_OFF);
    }
}

void write_lcd_mem(uint8_t *lcdmem, uint8_t bits, uint8_t bitmask, uint8_t state)
{
    if (state == SEG_ON) {
        /* Clear segments before writing */
        *lcdmem = (uint8_t)(*lcdmem & ~bitmask);

        /* Set visible segments */
        *lcdmem = (uint8_t)(*lcdmem | bits);
    }
    else if (state == SEG_OFF) {
        /* Clear segments */
        *lcdmem = (uint8_t)(*lcdmem & ~bitmask);
    }
    else if (state == SEG_ON_BLINK_ON) {
        /* Clear visible / blink segments before writing */
        *lcdmem = (uint8_t)(*lcdmem & ~bitmask);
        *(lcdmem + 0x20) = (uint8_t)(*(lcdmem + 0x20) & ~bitmask);

        /* Set visible / blink segments */
        *lcdmem = (uint8_t)(*lcdmem | bits);
        *(lcdmem + 0x20) = (uint8_t)(*(lcdmem + 0x20) | bits);
    }
    else if (state == SEG_ON_BLINK_OFF) {
        /* Clear visible segments before writing */
        *lcdmem = (uint8_t)(*lcdmem & ~bitmask);

        /* Set visible segments */
        *lcdmem = (uint8_t)(*lcdmem | bits);

        /* Clear blink segments */
        *(lcdmem + 0x20) = (uint8_t)(*(lcdmem + 0x20) & ~bitmask);
    }
    else if (state == SEG_OFF_BLINK_OFF) {
        /* Clear segments */
        *lcdmem = (uint8_t)(*lcdmem & ~bitmask);

        /* Clear blink segments */
        *(lcdmem + 0x20) = (uint8_t)(*(lcdmem + 0x20) & ~bitmask);
    }
}

char *itoa(uint32_t n, uint8_t digits, uint8_t blanks)
{
    uint8_t digits1 = digits;

    /* Preset result string */
    memcpy(itoa_str, "0000000", 7);

    /* Return empty string if number of digits is invalid (valid range for digits: 1-7) */
    if ((digits == 0) || (digits > 7)) {
        return (itoa_str);
    }

    /* Numbers 0 .. 180 can be copied from itoa_conversion_table without conversion */
    if (n <= 180) {
        if (digits >= 3) {
            memcpy(itoa_str + (digits - 3), itoa_conversion_table[n], 3);
        }
        /* digits == 1 || 2 */
        else {
            memcpy(itoa_str, itoa_conversion_table[n] + (3 - digits), digits);
        }
    }
    /* For n > 180 need to calculate string content */
    else {
        /* Calculate digits from least to most significant number */
        do {
            itoa_str[digits - 1] = n % 10 + '0';
            n /= 10;
        }
        while (--digits > 0);
    }

    /* Remove specified number of leading '0', always keep last one */
    uint8_t i = 0;
    while ((i < digits1 - 1) && (itoa_str[i] == '0')) {
        if (blanks > 0) {
            /* Convert only specified number of leading '0' */
            itoa_str[i] = ' ';
            blanks--;
        }

        i++;
    }

    return (itoa_str);
}

void display_value1(uint8_t segments, uint32_t value, uint8_t digits, uint8_t blanks, uint8_t disp_mode)
{
    char *str;

    str = itoa(value, digits, blanks);

    /* Display string in blink mode */
    display_chars(segments, str, disp_mode);
}

void display_symbol(uint8_t symbol, uint8_t mode)
{
    if (symbol <= LCD_SEG_L2_DP) {
        /* Get LCD memory address for symbol from table */
        uint8_t *lcdmem = (uint8_t *)segments_lcdmem[symbol];

        /* Get bits for symbol from table */
        uint8_t bits = segments_bitmask[symbol];

        /* Bitmask for symbols equals bits */
        uint8_t bitmask = bits;

        /* Write LCD memory */
        write_lcd_mem(lcdmem, bits, bitmask, mode);
    }
}

void display_char(uint8_t segment, char chr, uint8_t mode)
{
    /* Write to single 7-segment character */
    if ((segment >= LCD_SEG_L1_3) && (segment <= LCD_SEG_L2_DP)) {
        uint8_t bits; /* Bits to write */

        /* Get LCD memory address for segment from table */
        uint8_t *lcdmem = (uint8_t *)segments_lcdmem[segment];

        /* Get bitmask for character from table */
        uint8_t bitmask = segments_bitmask[segment];

        /* Get bits from font set */
        if ((chr >= 0x30) && (chr <= 0x5A)) {
            /* Use font set */
            bits = lcd_font[chr - 0x30];
        }
        else if (chr == 0x2D) {
            /* '-' not in font set */
            bits = BIT1;
        }
        else {
            /* Other characters map to ' ' (blank) */
            bits = 0;
        }

        /* When addressing LINE2 7-segment characters need to swap high- and low-nibble, */
        /* because LCD COM/SEG assignment is mirrored against LINE1 */
        if (segment >= LCD_SEG_L2_5) {
            uint8_t bits1 = ((bits << 4) & 0xF0) | ((bits >> 4) & 0x0F);
            bits = bits1;

            /* When addressing LCD_SEG_L2_5, need to convert ASCII '1' and 'L' to 1 bit, */
            /* because LCD COM/SEG assignment is special for this incomplete character */
            if (segment == LCD_SEG_L2_5) {
                if ((chr == '1') || (chr == 'L')) {
                    bits = BIT7;
                }
            }
        }

        /* Physically write to LCD memory */
        write_lcd_mem(lcdmem, bits, bitmask, mode);
    }
}

void display_chars(uint8_t segments, char *str, uint8_t mode)
{
    uint8_t length = 0; /* Write length */
    uint8_t char_start = 0; /* Starting point for consecutive write */

    switch (segments) {
        /* LINE1 */
        case LCD_SEG_L1_3_0:
            length = 4;
            char_start = LCD_SEG_L1_3;
            break;

        case LCD_SEG_L1_2_0:
            length = 3;
            char_start = LCD_SEG_L1_2;
            break;

        case LCD_SEG_L1_1_0:
            length = 2;
            char_start = LCD_SEG_L1_1;
            break;

        case LCD_SEG_L1_3_1:
            length = 3;
            char_start = LCD_SEG_L1_3;
            break;

        case LCD_SEG_L1_3_2:
            length = 2;
            char_start = LCD_SEG_L1_3;
            break;

        /* LINE2 */
        case LCD_SEG_L2_5_0:
            length = 6;
            char_start = LCD_SEG_L2_5;
            break;

        case LCD_SEG_L2_4_0:
            length = 5;
            char_start = LCD_SEG_L2_4;
            break;

        case LCD_SEG_L2_3_0:
            length = 4;
            char_start = LCD_SEG_L2_3;
            break;

        case LCD_SEG_L2_2_0:
            length = 3;
            char_start = LCD_SEG_L2_2;
            break;

        case LCD_SEG_L2_1_0:
            length = 2;
            char_start = LCD_SEG_L2_1;
            break;

        case LCD_SEG_L2_5_4:
            length = 2;
            char_start = LCD_SEG_L2_5;
            break;

        case LCD_SEG_L2_5_2:
            length = 4;
            char_start = LCD_SEG_L2_5;
            break;

        case LCD_SEG_L2_3_2:
            length = 2;
            char_start = LCD_SEG_L2_3;
            break;

        case LCD_SEG_L2_4_2:
            length = 3;
            char_start = LCD_SEG_L2_4;
            break;
    }

    /* Write to consecutive digits */
    for (uint8_t i = 0; i < length; i++) {
        /* Use single character routine to write display memory */
        display_char(char_start + i, *(str + i), mode);
    }
}

uint8_t switch_seg(uint8_t line, uint8_t index1, uint8_t index2)
{
    if (line == LINE1) {
        return index1;
    }
    /* line == LINE2 */
    else {
        return index2;
    }
}

void start_blink(void)
{
    LCDBBLKCTL |= LCDBLKMOD0;
}

void stop_blink(void)
{
    LCDBBLKCTL &= ~LCDBLKMOD0;
}

void clear_blink_mem(void)
{
    LCDBMEMCTL |= LCDCLRBM;
}

void set_blink_rate(uint8_t bits)
{
    LCDBBLKCTL &= ~(BIT7 | BIT6 | BIT5);
    LCDBBLKCTL |= bits;
}

void display_all_off(void)
{
    uint8_t *lcdptr = (uint8_t *)0x0A20;
    for (uint8_t i = 1; i <= 12; i++) {
        *lcdptr = 0x00;
        lcdptr++;
    }
}