Ramping UI

/*

 * ====================================================================
 *  Ramping UI for nanjg105c and a clicky switch by gChart (Gabriel Hart)
 *
 *  This firmware has its roots loosely based  on "Biscotti" by ToyKeeper
 *
 * ====================================================================
 *
 * 12 or more fast presses > Configuration mode
 *
 * Configuration Menu
 *   1: Memory toggle
 *   2: Stop-at-the-top toggle (without any user interaction, stops itself at turbo)
 *   3: Turbo Timer Toggle (turbo steps down to 50%)
 *   4: Reset to default configuration
 *
 * ====================================================================
 *
 * "Biscotti" firmware (attiny13a version of "Bistro")
 * This code runs on a single-channel driver with attiny13a MCU.
 * It is intended specifically for nanjg 105d drivers from Convoy.
 *
 * Copyright (C) 2015 Selene Scriven
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *
 * ATTINY13 Diagram
 *         ----
 *       -|1  8|- VCC
 *       -|2  7|- Voltage ADC
 *       -|3  6|-
 *   GND -|4  5|- PWM (Nx7135)
 *         ----
 *
 * FUSES
 *    I use these fuse settings on attiny13
 *    Low:  0x75
 *    High: 0xff
 *
 * CALIBRATION
 *
 *   To find out what values to use, flash the driver with battcheck.hex
 *   and hook the light up to each voltage you need a value for.  This is
 *   much more reliable than attempting to calculate the values from a
 *   theoretical formula.
 *
 *   Same for off-time capacitor values.  Measure, don't guess.
 */
// Choose your MCU here, or in the build script
#define ATTINY 13
#define NANJG_LAYOUT  // specify an I/O pin layout
// Also, assign I/O pins in this file:
#include "../tk-attiny.h"

#define DEFAULTS 0b00000100 // No memory, doesn't stop at the top, turbo timer is enabled

#define FAST  0xA3        // fast PWM both channels
#define PHASE 0xA1        // phase-correct PWM both channels
#define VOLTAGE_MON      // Comment out to disable LVP

#define BLINK_BRIGHTNESS    40 // output to use for blinks in config mode
#define BLINK_SPEED      750 // ms per normal-speed blink

#define USE_BATTCHECK      // Enable battery check mode
#define BATTCHECK_8bars  // up to 8 blinks

#define TURBO_MINUTES 5 // when turbo timer is enabled, how long before stepping down
#define TICKS_PER_MINUTE 120 // used for Turbo Timer timing
#define TURBO_LOWER 128  // the PWM level to use when stepping down
#define TURBO_THRESHOLD sizeof(ramp_values)-5 // Min output level that we consider to be turbo?

#define RAMP_TIME  5  // number of seconds to go from min brightness to max brightness

#define RAMP_SIZE sizeof(ramp_values)
//#define RAMP_VALUES 1,1,1,1,1,2,2,2,2,3,3,4,5,5,6,7,8,9,10,11,13,14,16,18,20,22,24,26,29,32,34,38,41,44,48,51,55,60,64,68,73,78,84,89,95,101,107,113,120,127,134,142,150,158,166,175,184,193,202,212,222,233,244,255
#define RAMP_VALUES 5,5,5,5,5,6,6,6,6,7,7,8,8,9,10,11,12,13,14,15,17,18,20,22,23,25,28,30,32,35,38,41,44,47,51,55,59,63,67,71,76,81,86,92,97,103,109,116,122,129,136,144,151,159,167,176,185,194,203,213,223,233,244,255

// Calibrate voltage and OTC in this file:
#include "../tk-calibration.h"

/*
 * =========================================================================
 */

// Ignore a spurious warning, we did the cast on purpose
#pragma GCC diagnostic ignored "-Wint-to-pointer-cast"

#include <avr/pgmspace.h>
#include <avr/interrupt.h>
#include <avr/eeprom.h>
#include <avr/sleep.h>
#include <string.h>

#define OWN_DELAY          // Don't use stock delay functions.
#define USE_DELAY_S      // Also use _delay_s(), not just _delay_ms()
#include "../tk-delay.h"

#include "../tk-voltage.h"

register uint8_t options asm("r6");
register uint8_t eepos asm("r7");

#define NUM_FP_BYTES 3
uint8_t fast_presses[NUM_FP_BYTES] __attribute__ ((section (".noinit")));

#define RAMPING_UP 0
#define RAMPING_DOWN 1
uint8_t ramp_direction __attribute__ ((section (".noinit")));
uint8_t ramp_stopped __attribute__ ((section (".noinit")));
uint8_t output __attribute__ ((section (".noinit")));
uint8_t output_in_eeprom;

PROGMEM const uint8_t ramp_values[]  = { RAMP_VALUES };

inline uint8_t memory_is_enabled()   { return (options     ) & 0b00000001; }
inline uint8_t stop_at_the_top()     { return (options >> 1) & 0b00000001; }
inline uint8_t ttimer_is_enabled()   { return (options >> 2) & 0b00000001; }

void save_output() {  // save the current output level (with wear leveling)
    uint8_t oldpos=eepos;
    eepos = (eepos+1) & ((EEPSIZE/2)-1);  // wear leveling, use next cell
    eeprom_write_byte((uint8_t *)(eepos), output);  // save current state
    eeprom_write_byte((uint8_t *)(oldpos), 0xff);     // erase old state
}

#define OPT_options (EEPSIZE-1)
void save_state() {  // central method for writing complete state
    save_output();
    eeprom_write_byte((uint8_t *)OPT_options, options);
}

inline void reset_state() {
    output_in_eeprom = 1;
    options = DEFAULTS;  // 3 brightness levels with memory
    save_state();
}

inline void restore_state() {
    uint8_t eep;
    uint8_t first = 1;
    uint8_t i;
    // find the output level data
    for(i=0; i<(EEPSIZE-6); i++) {
        eep = eeprom_read_byte((const uint8_t *)i);
        if (eep != 0xff) {
            eepos = i;
            output_in_eeprom = eep;
            first = 0;
            break;
        }
    }
    // if no output level was found, assume this is the first boot
    if (first) {
        reset_state();
        return;
    }

    // load other config values
    options = eeprom_read_byte((uint8_t *)OPT_options);
}

void set_pwm(uint8_t pwm) {
    TCCR0A = PHASE;
    TCCR0B = 0x01;
    PWM_LVL = pwm;
}

void set_level(uint8_t level) {
    if (level == 0) { set_pwm(0); }
    else { set_pwm( pgm_read_byte(ramp_values + level - 1) ); }
}

void blink(uint8_t val, uint16_t speed)
{
    for (; val>0; val--)
    {
        set_pwm(BLINK_BRIGHTNESS);
        _delay_ms(speed);
        set_pwm(0);
        _delay_ms(speed);
        _delay_ms(speed);
    }
}

void toggle_options(uint8_t value, uint8_t num) {
    blink(num, BLINK_SPEED/4);  // indicate which option number this is
    uint8_t temp = options;
    options = value;
    save_state();
    blink(32, 500/32); // "buzz" for a while to indicate the active toggle window

    // if the user didn't click, reset the value and return
    options = temp;
    save_state();
    _delay_s();
}

inline uint8_t we_did_a_fast_press() {
    uint8_t i = NUM_FP_BYTES-1;
    while (i && (fast_presses[i] == fast_presses[i-1] )){ --i; }
    return !i;
}
inline void increment_fast_presses() {
    uint8_t i;
    for(i=0; i<NUM_FP_BYTES; i++) { fast_presses[i]++; }
}

void reset_fast_presses() {
    uint8_t i;
    for(i=0; i<NUM_FP_BYTES; i++) { fast_presses[i] = 0; }
}

int main(void)
{

    DDRB |= (1 << PWM_PIN);  // Set PWM pin to output, enable main channel

    restore_state(); // Read config values and saved state

  if ( we_did_a_fast_press() ) {
    increment_fast_presses();
        ramp_stopped = !ramp_stopped;

        if(fast_presses[0] == 2) {  // jump to turbo on a double-tap from anywhere
            output = RAMP_SIZE;
            ramp_stopped = 1;
        }

    if(ramp_stopped) { save_output(); }

  } else { // Long press
    reset_fast_presses();
        ramp_direction = RAMPING_UP;
    if( memory_is_enabled() ) {
      output = output_in_eeprom;
            ramp_stopped = 1;
    }
    else {
      output = 1;
            ramp_stopped = 0;
    }
  }

    #ifdef VOLTAGE_MON
    ADC_on();
    #else
    ADC_off();
    #endif

    uint16_t ticks = 0;

#ifdef VOLTAGE_MON
    uint8_t lowbatt_cnt = 0;
    uint8_t voltage;
    ADCSRA |= (1 << ADSC); // Make sure voltage reading is running for later
#endif

    while(1) {
        if (fast_presses[0] >= 12) {  // Config mode if 12 or more fast presses
            _delay_s();    // wait for user to stop fast-pressing button
            reset_fast_presses(); // exit this mode after one use

            toggle_options((options ^ 0b00000001), 1); // memory
            toggle_options((options ^ 0b00000010), 2); // stop at the top
            toggle_options((options ^ 0b00000100), 3); // turbo timer
            toggle_options(DEFAULTS, 4); // reset to defaults
        }
        else if (fast_presses[0] == 3) {
        //else if (output == BATT_CHECK) {
             blink(battcheck(), BLINK_SPEED/4);
             _delay_s(); _delay_s();
            // shouldn't need to worry about resetting fast_presses here, but may need to later
        }
    else if ( !ramp_stopped ) {
            set_level(output);
            if(output == 1 || output == RAMP_SIZE) { _delay_s(); }  // pause for a second at the lowest & highest levels

            if( (ramp_direction == RAMPING_DOWN && output == 1) || (ramp_direction == RAMPING_UP && output == RAMP_SIZE) ) {
                ramp_direction = !ramp_direction;
            }

            if( output == RAMP_SIZE && stop_at_the_top() ) {
                ramp_stopped = 1;
            }

            if(ramp_direction == RAMPING_UP) { output++; }
            else { output--; }

            _delay_ms(RAMP_TIME*1000/RAMP_SIZE);

            // if we've been ramping around for more than half a second, reset the fast_presses
            ticks = ticks + (RAMP_TIME*1000/RAMP_SIZE);
            if(ticks > 500) {
                ticks = 0;
                reset_fast_presses();
            }

    }
        else {
            if ((output >= TURBO_THRESHOLD) && ( ttimer_is_enabled() ) && (ticks > (TURBO_MINUTES * TICKS_PER_MINUTE))) {
                set_pwm(TURBO_LOWER);
            }
      else {
        ticks ++; // count ticks for turbo timer
                set_level(output);
      }

            _delay_ms(500);  // Otherwise, just sleep.
      reset_fast_presses();
        }
#ifdef VOLTAGE_MON
        if (ADCSRA & (1 << ADIF)) {  // if a voltage reading is ready
            voltage = ADCH;  // get the waiting value

            if (voltage < ADC_LOW) { // See if voltage is lower than what we were looking for
                lowbatt_cnt ++;
            } else {
                lowbatt_cnt = 0;
            }

            if (lowbatt_cnt >= 8) {  // See if it's been low for a while, and maybe step down
                if (output > 1) {  // not yet at the lowest level
                    output = (output>>1); // divide output in half using bitwise operators
                } else { // Can't go any lower
                    set_pwm(0); // Turn off the light
                    set_sleep_mode(SLEEP_MODE_PWR_DOWN); // Power down as many components as possible
                    sleep_mode();
                }
                set_level(output);
                lowbatt_cnt = 0;
                _delay_s(); // Wait before lowering the level again
            }

            ADCSRA |= (1 << ADSC); // Make sure conversion is running for next time through
        }
#endif  // ifdef VOLTAGE_MON
    }
}