Add battery management

example_keyboards
tmk 10 years ago
parent 807ed33a9a
commit 02939ab1d8

@ -4,6 +4,7 @@ SRC += serial_uart.c \
rn42/suart.S \
rn42/rn42.c \
rn42/rn42_task.c \
rn42/battery.c \
rn42/main.c
OPT_DEFS += -DPROTOCOL_RN42

@ -0,0 +1,119 @@
#include <avr/io.h>
#include <util/delay.h>
#include "battery.h"
/*
* Battery
*/
void battery_init(void)
{
// blink
battery_led(LED_ON); _delay_ms(500);
battery_led(LED_OFF); _delay_ms(500);
battery_led(LED_ON); _delay_ms(500);
battery_led(LED_OFF); _delay_ms(500);
// LED indicates charger status
battery_led(LED_CHARGER);
// ADC setting for voltage monitor
// Ref:2.56V band-gap, Input:ADC0(PF0), Prescale:128(16MHz/128=125KHz)
ADMUX = (1<<REFS1) | (1<<REFS0);
ADCSRA = (1<<ADPS2) | (1<<ADPS1) | (1<<ADPS0);
ADCSRA |= (1<<ADEN);
}
// Indicator for battery
void battery_led(battery_led_t val)
{
if (val == LED_TOGGLE) {
// Toggle LED
DDRF |= (1<<5);
PINF |= (1<<5);
} else if (val == LED_ON) {
// On overriding charger status
DDRF |= (1<<5);
PORTF &= ~(1<<5);
} else if (val == LED_OFF) {
// Off overriding charger status
DDRF |= (1<<5);
PORTF |= (1<<5);
} else {
// Display charger status
DDRF &= ~(1<<5);
PORTF &= ~(1<<5);
}
}
bool battery_charging(void)
{
if (!(USBSTA&(1<<VBUS))) return false;
// MCP73831:STAT
// HiZ: Shutdown/No Battery
// Low: Charging
// Hi: Charged
// preserve last register status
uint8_t ddrf_prev = DDRF;
uint8_t portf_prev = PORTF;
// Input with pullup
DDRF &= ~(1<<5);
PORTF |= (1<<5);
_delay_ms(1);
bool charging = PINF&(1<<5) ? false : true;
// restore last register status
DDRF = (DDRF&~(1<<5)) | (ddrf_prev&(1<<5));
PORTF = (PORTF&~(1<<5)) | (portf_prev&(1<<5));
return charging;
}
// Returns voltage in mV
uint16_t battery_voltage(void)
{
volatile uint16_t bat;
//ADCSRA |= (1<<ADEN);
// discard first result
ADCSRA |= (1<<ADSC);
while (ADCSRA & (1<<ADSC)) ;
bat = ADC;
// discard second result
ADCSRA |= (1<<ADSC);
while (ADCSRA & (1<<ADSC)) ;
bat = ADC;
ADCSRA |= (1<<ADSC);
while (ADCSRA & (1<<ADSC)) ;
bat = ADC;
//ADCSRA &= ~(1<<ADEN);
return (bat - BATTERY_ADC_OFFSET) * BATTERY_ADC_RESOLUTION;
}
static bool low_voltage(void) {
static bool low = false;
uint16_t v = battery_voltage();
if (v < BATTERY_VOLTAGE_LOW_LIMIT) {
low = true;
} else if (v > BATTERY_VOLTAGE_LOW_RECOVERY) {
low = false;
}
return low;
}
battery_status_t battery_status(void)
{
if (USBSTA&(1<<VBUS)) {
/* powered */
return battery_charging() ? CHARGING : FULL_CHARGED;
} else {
/* not powered */
return low_voltage() ? LOW_VOLTAGE : DISCHARGING;
}
}

@ -0,0 +1,34 @@
#ifndef POWER_H
#define POWER_H
#include <stdint.h>
#include <stdbool.h>
typedef enum {
FULL_CHARGED,
CHARGING,
DISCHARGING,
LOW_VOLTAGE,
} battery_status_t;
typedef enum {
LED_CHARGER = 0,
LED_ON,
LED_OFF,
LED_TOGGLE,
} battery_led_t;
/* Battery API */
void battery_init(void);
void battery_led(battery_led_t val);
bool battery_charging(void);
uint16_t battery_voltage(void);
battery_status_t battery_status(void);
#define BATTERY_VOLTAGE_LOW_LIMIT 3500
#define BATTERY_VOLTAGE_LOW_RECOVERY 3700
// ADC offset:16, resolution:5mV
#define BATTERY_ADC_OFFSET 16
#define BATTERY_ADC_RESOLUTION 5
#endif

@ -9,6 +9,7 @@
#include "print.h"
#include "timer.h"
#include "command.h"
#include "battery.h"
static bool config_mode = false;
static bool force_usb = false;
@ -24,65 +25,9 @@ static void status_led(bool on)
}
}
static void battery_adc_init(void)
{
ADMUX = (1<<REFS1) | (1<<REFS0); // Ref:2.56V band-gap, Input:ADC0(PF0)
ADCSRA = (1<<ADPS2) | (1<<ADPS1) | (1<<ADPS0); // Prescale:128 16MHz/128=125KHz
ADCSRA |= (1<<ADEN); // enable ADC
}
static uint16_t battery_adc(void)
{
volatile uint16_t bat;
ADCSRA |= (1<<ADEN);
// discard first result
ADCSRA |= (1<<ADSC);
while (ADCSRA & (1<<ADSC)) ;
bat = ADC;
// discard second result
ADCSRA |= (1<<ADSC);
while (ADCSRA & (1<<ADSC)) ;
bat = ADC;
ADCSRA |= (1<<ADSC);
while (ADCSRA & (1<<ADSC)) ;
bat = ADC;
ADCSRA &= ~(1<<ADEN);
return bat;
}
static void battery_led(bool on)
{
if (on) {
DDRF |= (1<<5);
PORTF &= ~(1<<5); // Low
} else {
DDRF &= ~(1<<5);
PORTF &= ~(1<<5); // HiZ
}
}
static bool battery_charging(void)
{
// MCP73831:STAT
// Hi-Z: Shutdown/No Battery
// Low: Charging
// Hi: Charged
DDRF &= ~(1<<5);
PORTF |= (1<<5);
return PINF&(1<<5) ? false : true;
}
void rn42_task_init(void)
{
battery_adc_init();
// battery charging(HiZ)
DDRF &= ~(1<<5);
PORTF &= ~(1<<5);
battery_init();
}
void rn42_task(void)
@ -136,7 +81,12 @@ void rn42_task(void)
}
}
/* Battery monitor */
/* Low voltage alert */
if (battery_status() == LOW_VOLTAGE) {
battery_led(LED_ON);
} else {
battery_led(LED_CHARGER);
}
/* Connection monitor */
if (rn42_linked()) {
@ -214,12 +164,13 @@ bool command_extra(uint8_t code)
xprintf("config_mode: %X\n", config_mode);
xprintf("VBUS: %X\n", USBSTA&(1<<VBUS));
xprintf("battery_charging: %X\n", battery_charging());
xprintf("battery_status: %X\n", battery_status());
return true;
case KC_B:
// battery monitor
t = timer_read32()/1000;
b = battery_adc();
xprintf("BAT: %umV(%04X)\t", (b-16)*5, b);
b = battery_voltage();
xprintf("BAT: %umV\t", b);
xprintf("%02u:", t/3600);
xprintf("%02u:", t%3600/60);
xprintf("%02u\n", t%60);

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