~toykeeper/flashlight-firmware/trunk

/*
 * Generic clicky-switch-with-offtime-cap firmware.
 * Expects a FET+1 style driver, supports two independent power channels.
 * Similar to blf-a6.c but minus the end-user config options.
 * (expects to be configured at compile-time, not runtime)
 *
 * 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/>.
 *
 *
 * NANJG 105C Diagram
 *           ---
 *         -|   |- VCC
 *     OTC -|   |- Voltage ADC
 *  Star 3 -|   |- PWM (FET)
 *     GND -|   |- PWM (1x7135)
 *           ---
 *
 * FUSES
 *      (check bin/flash*.sh for recommended values)
 *
 * STARS
 *      Star 2 = second PWM output channel
 *      Star 3 = mode memory if soldered, no memory by default
 *      Star 4 = Capacitor for off-time
 *
 * VOLTAGE
 *      Resistor values for voltage divider (reference BLF-VLD README for more info)
 *      Reference voltage can be anywhere from 1.0 to 1.2, so this cannot be all that accurate
 *
 *           VCC
 *            |
 *           Vd (~.25 v drop from protection diode)
 *            |
 *          1912 (R1 19,100 ohms)
 *            |
 *            |---- PB2 from MCU
 *            |
 *          4701 (R2 4,700 ohms)
 *            |
 *           GND
 *
 *   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 ATTINY 25
// FIXME: make 1-channel vs 2-channel power a single #define option
#define FET_7135_LAYOUT  // specify an I/O pin layout
// Also, assign I/O pins in this file:
#include "../tk-attiny.h"

/*
 * =========================================================================
 * Settings to modify per driver
 */

//#define FAST 0x23           // fast PWM channel 1 only
//#define PHASE 0x21          // phase-correct PWM channel 1 only
#define FAST 0xA3           // fast PWM both channels
#define PHASE 0xA1          // phase-correct PWM both channels

#define VOLTAGE_MON         // Comment out to disable LVP

#define OFFTIM3             // Use short/med/long off-time presses
                            // instead of just short/long

// output to use for blinks on battery check mode (primary PWM level, alt PWM level)
// Use 20,0 for a single-channel driver or 0,20 for a two-channel driver
#define BLINK_BRIGHTNESS    0,20

// Mode group 1
#define NUM_MODES           7
// PWM levels for the big circuit (FET or Nx7135)
#define MODESNx             0,0,0,7,56,137,255
// PWM levels for the small circuit (1x7135)
#define MODES1x             3,20,110,255,255,255,0
// PWM speed for each mode
#define MODES_PWM           PHASE,FAST,FAST,FAST,FAST,FAST,PHASE
// Hidden modes are *before* the lowest (moon) mode, and should be specified
// in reverse order.  So, to go backward from moon to turbo to strobe to
// battcheck, use BATTCHECK,STROBE,TURBO .
#define NUM_HIDDEN          4
#define HIDDENMODES         BIKING_STROBE,BATTCHECK,STROBE,TURBO
#define HIDDENMODES_PWM     PHASE,PHASE,PHASE,PHASE
#define HIDDENMODES_ALT     0,0,0,0   // Zeroes, same length as NUM_HIDDEN

#define TURBO     255       // Convenience code for turbo mode
#define BATTCHECK 254       // Convenience code for battery check mode
// Uncomment to enable tactical strobe mode
#define STROBE    253       // Convenience code for strobe mode
// Uncomment to unable a 2-level stutter beacon instead of a tactical strobe
#define BIKING_STROBE 252   // Convenience code for biking strobe mode
// comment out to use minimal version instead (smaller)
#define FULL_BIKING_STROBE

#define NON_WDT_TURBO            // enable turbo step-down without WDT
// How many timer ticks before before dropping down.
// Each timer tick is 500ms, so "60" would be a 30-second stepdown.
// Max value of 255 unless you change "ticks"
#define TURBO_TIMEOUT       90

// 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/io.h>
//#include <avr/interrupt.h>
#include <avr/eeprom.h>
#include <avr/sleep.h>
//#include <avr/power.h>

#define OWN_DELAY           // Don't use stock delay functions.
#define USE_DELAY_MS        // use _delay_ms()
#define USE_DELAY_S         // Also use _delay_s(), not just _delay_ms()
#include "../tk-delay.h"
#define USE_BATTCHECK
//#define BATTCHECK_4bars
#define BATTCHECK_8bars
//#define BATTCHECK_VpT
#define BLINK_SPEED 500
#include "../tk-voltage.h"

/*
 * global variables
 */

// Config / state variables
uint8_t eepos = 0;
uint8_t memory = 0;        // mode memory, or not (set via soldered star)
uint8_t mode_idx = 0;      // current or last-used mode number

// NOTE: Only '1' is known to work; -1 will probably break and is untested.
// In other words, short press goes to the next (higher) mode,
// medium press goes to the previous (lower) mode.
#define mode_dir 1
// total length of current mode group's array
#define mode_cnt solid_modes+NUM_HIDDEN
// number of regular non-hidden modes in current mode group
#define solid_modes NUM_MODES
// number of hidden modes in the current mode group
// (hardcoded because both groups have the same hidden modes)
//uint8_t hidden_modes = NUM_HIDDEN;  // this is never used


// Modes (gets set when the light starts up based on saved config values)
PROGMEM const uint8_t modesNx[] = { MODESNx, HIDDENMODES };
PROGMEM const uint8_t modes1x[] = { MODES1x, HIDDENMODES_ALT };
PROGMEM const uint8_t modes_pwm[] = { MODES_PWM, HIDDENMODES_PWM };

void save_state() {  // central method for writing (with wear leveling)
    // a single 16-bit write uses less ROM space than two 8-bit writes
    uint8_t eep;
    uint8_t oldpos=eepos;

    eepos = (eepos+1) & (EEPSIZE-1);  // wear leveling, use next cell

    eep = mode_idx;
    eeprom_write_byte((uint8_t *)(eepos), eep);      // save current state
    eeprom_write_byte((uint8_t *)(oldpos), 0xff);    // erase old state
}

void restore_state() {
    uint8_t eep;
    // find the config data
    for(eepos=0; eepos<EEPSIZE; eepos++) {
        eep = eeprom_read_byte((const uint8_t *)eepos);
        if (eep != 0xff) break;
    }
    // unpack the config data
    if (eepos < EEPSIZE) {
        mode_idx = eep;
    }
    // unnecessary, save_state handles wrap-around
    // (and we don't really care about it skipping cell 0 once in a while)
    //else eepos=0;
}

inline void next_mode() {
    mode_idx += 1;
    if (mode_idx >= solid_modes) {
        // Wrap around, skipping the hidden modes
        // (note: this also applies when going "forward" from any hidden mode)
        mode_idx = 0;
    }
}

#ifdef OFFTIM3
inline void prev_mode() {
    if (mode_idx == solid_modes) {
        // If we hit the end of the hidden modes, go back to moon
        mode_idx = 0;
    } else if (mode_idx > 0) {
        // Regular mode: is between 1 and TOTAL_MODES
        mode_idx -= 1;
    } else {
        // Otherwise, wrap around (this allows entering hidden modes)
        mode_idx = mode_cnt - 1;
    }
}
#endif

void set_output(uint8_t pwm1, uint8_t pwm2) {
    // Need PHASE to properly turn off the light
    if ((pwm1==0) && (pwm2==0)) {
        TCCR0A = PHASE;
    }
    PWM_LVL = pwm1;
    ALT_PWM_LVL = pwm2;
}

void set_mode(uint8_t mode) {
    TCCR0A = pgm_read_byte(modes_pwm + mode);
    set_output(pgm_read_byte(modesNx + mode), pgm_read_byte(modes1x + mode));
    /*
    // Only set output for solid modes
    uint8_t out = pgm_read_byte(modesNx + mode);
    if ((out < 250) || (out == 255)) {
        set_output(pgm_read_byte(modesNx + mode), pgm_read_byte(modes1x + mode));
    }
    */
}

void blink(uint8_t val)
{
    for (; val>0; val--)
    {
        set_output(BLINK_BRIGHTNESS);
        _delay_ms(BLINK_SPEED / 5);
        set_output(0,0);
        _delay_ms(BLINK_SPEED * 4 / 5);
    }
}

int main(void)
{
    uint8_t cap_val;

    // Read the off-time cap *first* to get the most accurate reading
    // Start up ADC for capacitor pin
    DIDR0 |= (1 << CAP_DIDR);                           // disable digital input on ADC pin to reduce power consumption
    ADMUX  = (1 << V_REF) | (1 << ADLAR) | CAP_CHANNEL; // 1.1v reference, left-adjust, ADC3/PB3
    ADCSRA = (1 << ADEN ) | (1 << ADSC ) | ADC_PRSCL;   // enable, start, prescale

    // Wait for completion
    while (ADCSRA & (1 << ADSC));
    // Start again as datasheet says first result is unreliable
    ADCSRA |= (1 << ADSC);
    // Wait for completion
    while (ADCSRA & (1 << ADSC));
    cap_val = ADCH; // save this for later

    // All ports default to input, but turn pull-up resistors on for the stars (not the ADC input!  Made that mistake already)
    // only one star, because one is used for PWM channel 2
    // and the other is used for the off-time capacitor
    PORTB = (1 << STAR3_PIN);

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

    // Set timer to do PWM for correct output pin and set prescaler timing
    //TCCR0A = 0x23; // phase corrected PWM is 0x21 for PB1, fast-PWM is 0x23
    //TCCR0B = 0x01; // pre-scaler for timer (1 => 1, 2 => 8, 3 => 64...)
    TCCR0A = PHASE;
    // Set timer to do PWM for correct output pin and set prescaler timing
    TCCR0B = 0x01; // pre-scaler for timer (1 => 1, 2 => 8, 3 => 64...)

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


    if (cap_val > CAP_SHORT) {
        // Indicates they did a short press, go to the next mode
        next_mode(); // Will handle wrap arounds
#ifdef OFFTIM3
    } else if (cap_val > CAP_MED) {
        // User did a medium press, go back one mode
        prev_mode(); // Will handle "negative" modes and wrap-arounds
#endif
    } else {
        // Long press, keep the same mode
        // ... or reset to the first mode
        if (! memory) {
            // Reset to the first mode
            mode_idx = 0;
        }
    }
    save_state();

    // Turn off ADC
    //ADC_off();

    // Charge up the capacitor by setting CAP_PIN to output
    DDRB  |= (1 << CAP_PIN);    // Output
    PORTB |= (1 << CAP_PIN);    // High

    // Turn features on or off as needed
    #ifdef VOLTAGE_MON
    ADC_on();
    #else
    ADC_off();
    #endif
    //ACSR   |=  (1<<7); //AC off

    // Enable sleep mode set to Idle that will be triggered by the sleep_mode() command.
    // Will allow us to go idle between WDT interrupts
    //set_sleep_mode(SLEEP_MODE_IDLE);  // not used due to blinky modes

    uint8_t output;
#ifdef NON_WDT_TURBO
    uint8_t ticks = 0;
#endif
#ifdef VOLTAGE_MON
    uint8_t lowbatt_cnt = 0;
    uint8_t i = 0;
    uint8_t voltage;
    // Make sure voltage reading is running for later
    ADCSRA |= (1 << ADSC);
#endif
    while(1) {
        output = pgm_read_byte(modesNx + mode_idx);
        // placeholder in case strobe isn't defined, should get compiled out by -Os
        if (0) {}
#ifdef STROBE
        else if (output == STROBE) {
            // 10Hz tactical strobe
            set_output(255,0);
            _delay_ms(50);
            set_output(0,0);
            _delay_ms(50);
        }
#endif // ifdef STROBE
#ifdef BIKING_STROBE
        else if (output == BIKING_STROBE) {
            // 2-level stutter beacon for biking and such
#ifdef FULL_BIKING_STROBE
            // normal version
            for(i=0;i<4;i++) {
                set_output(255,0);
                _delay_ms(5);
                set_output(0,255);
                _delay_ms(65);
            }
            _delay_ms(720);
#else
            // small/minimal version
            set_output(255,0);
            _delay_ms(10);
            set_output(0,255);
            _delay_s();
#endif
        }
#endif  // ifdef BIKING_STROBE
#ifdef BATTCHECK
        else if (output == BATTCHECK) {
            // blink zero to five times to show voltage
            // (~0%, ~25%, ~50%, ~75%, ~100%, >100%)
            blink(battcheck());
            // wait between readouts
            _delay_s(); _delay_s();
        }
#endif // ifdef BATTCHECK
        else {  // Regular non-hidden solid mode
            set_mode(mode_idx);
            // This part of the code will mostly replace the WDT tick code.
#ifdef NON_WDT_TURBO
            // Do some magic here to handle turbo step-down
            //if (ticks < 255) ticks++;  // don't roll over
            ticks ++;  // actually, we don't care about roll-over prevention
            if ((ticks > TURBO_TIMEOUT) 
                    && (output == TURBO)) {
                mode_idx = solid_modes - 2; // step down to second-highest mode
                set_mode(mode_idx);
                save_state();
            }
#endif
            // Otherwise, just sleep.
            _delay_ms(500);
        }
#ifdef VOLTAGE_MON
#if 1
        if (ADCSRA & (1 << ADIF)) {  // if a voltage reading is ready
            voltage = ADCH; // get_voltage();
            // See if voltage is lower than what we were looking for
            //if (voltage < ((mode_idx <= 1) ? ADC_CRIT : ADC_LOW)) {
            if (voltage < ADC_LOW) {
                lowbatt_cnt ++;
            } else {
                lowbatt_cnt = 0;
            }
            // See if it's been low for a while, and maybe step down
            if (lowbatt_cnt >= 8) {
                // DEBUG: blink on step-down:
                //set_output(0,0);  _delay_ms(100);
                i = mode_idx; // save space by not accessing mode_idx more than necessary
                // properly track hidden vs normal modes
                if (i >= solid_modes) {
                    // step down from blinky modes to medium
                    i = 2;
                } else if (i > 0) {
                    // step down from solid modes one at a time
                    i -= 1;
                } else { // Already at the lowest mode
                    i = 0;
                    // Turn off the light
                    set_output(0,0);
                    // Power down as many components as possible
                    set_sleep_mode(SLEEP_MODE_PWR_DOWN);
                    sleep_mode();
                }
                set_mode(i);
                mode_idx = i;
                save_state();
                lowbatt_cnt = 0;
                // Wait at least 2 seconds before lowering the level again
                _delay_ms(250);  // this will interrupt blinky modes
            }

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

    //return 0; // Standard Return Code
}