flm01/avr/main.c

390 lines
10 KiB
C

//
// main.c : AVR uC code for flukso sensor board
//
// Copyright (c) 2008-2009 jokamajo.org
// 2010 flukso.net
//
// 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 2
// 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, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
//
// $Id$
#include <string.h>
#include <stdlib.h>
#include "wiring/wiring_private.h"
#include "main.h"
#include <avr/io.h>
// pin/register/ISR definitions
#include <avr/interrupt.h>
// eeprom library
#include <avr/eeprom.h>
// watchdog timer library
#include <avr/wdt.h>
// variable declarations
volatile struct state aux[4] = {{false, false, false, START, 0}, {false, false, false, START, 0}, {false, false, false, START, 0}, {false, false, false, START, 0}};
volatile struct sensor EEMEM EEPROM_measurements[4] = {{SENSOR0, START}, {SENSOR1, START}, {SENSOR2, START}, {SENSOR3, START}};
volatile struct sensor measurements[4];
volatile struct time_struct time = {false, 0};
volatile uint8_t muxn = 0;
volatile uint16_t timer = 0;
// interrupt service routine for INT0
ISR(INT0_vect) {
pulse_add(&measurements[2], &aux[2], PULSE_CONST_2, PULSE_HALF_2);
}
// interrupt service routine for INT1
ISR(INT1_vect) {
pulse_add(&measurements[3], &aux[3], PULSE_CONST_3, PULSE_HALF_3);
}
// interrupt service routine for PCI2 (PCINT20)
/**
ISR(PCINT2_vect) {
if (aux[4].toggle == false) {
aux[4].toggle = true;
}
else {
pulse_add(&measurements[4], &aux[4], PULSE_CONST_4, PULSE_HALF_4);
}
}
**/
void pulse_add(volatile struct sensor *measurement, volatile struct state *aux, uint32_t pulse_const, uint32_t pulse_half) {
measurement->value += pulse_const;
if (aux->half == true) {
measurement->value += 1;
}
if (pulse_half) {
aux->half = !aux->half;
}
aux->pulse = true;
aux->time = time.ms;
}
// interrupt service routine for ADC
ISR(TIMER2_COMPA_vect) {
#if DBG > 0
PORTD |= (1<<PD4);
#endif
// read ADC result
// add to nano(Wh) counter
#if PHASE == 2
MacU16X16to32(aux[0].nano, METERCONST, ADC);
#else
MacU16X16to32(aux[muxn].nano, METERCONST, ADC);
#endif
if (aux[muxn].nano > WATT) {
measurements[muxn].value++;
aux[muxn].pulse = true;
aux[muxn].nano -= WATT;
aux[muxn].pulse_count++;
}
if (timer == SECOND) {
aux[muxn].nano_start = aux[muxn].nano_end;
aux[muxn].nano_end = aux[muxn].nano;
aux[muxn].pulse_count_final = aux[muxn].pulse_count;
aux[muxn].pulse_count = 0;
aux[muxn].power = true;
}
// cycle through the available ADC input channels (0 and 1)
muxn++;
if (!(muxn &= 0x1)) timer++;
if (timer > SECOND) timer = 0;
// We have timer interrupts occcuring at a frequency of 1250Hz.
// In order to map this to 1000Hz (=ms) we have to skip every fifth interrupt.
if (!time.skip) time.ms++;
time.skip = (((time.ms & 0x3) == 3) && !time.skip) ? true : false;
ADMUX &= 0xF8;
ADMUX |= muxn;
// start a new ADC conversion
ADCSRA |= (1<<ADSC);
#if DBG > 0
PORTD &= ~(1<<PD4);
#endif
#if DBG > 1
aux[muxn].nano = WATT+1;
timer = SECOND;
#endif
}
// interrupt service routine for analog comparator
ISR(ANALOG_COMP_vect) {
uint8_t i;
//debugging:
//measurements[3].value = END3;
//measurements[2].value = END2;
//measurements[1].value = END1;
//measurements[0].value = END0;
//disable uC sections to consume less power while writing to EEPROM
//disable UART Tx and Rx:
UCSR0B &= ~((1<<RXEN0) | (1<<TXEN0));
//disable ADC:
ADCSRA &= ~(1<<ADEN);
for (i=0; i<4; i++)
eeprom_write_block((const void*)&measurements[i].value, (void*)&EEPROM_measurements[i].value, 4);
//indicate writing to EEPROM has finished by lighting up the green LED
PORTB |= (1<<PB5);
//enable UART Tx and Rx:
UCSR0B |= (1<<RXEN0) | (1<<TXEN0);
// enable ADC and start a first ADC conversion
ADCSRA |= (1<<ADEN) | (1<<ADSC);
printString("msg BROWN-OUT\n");
}
// interrupt service routine for watchdog timeout
ISR(WDT_vect) {
uint8_t i;
for (i=0; i<4; i++)
eeprom_write_block((const void*)&measurements[i].value, (void*)&EEPROM_measurements[i].value, 4);
printString("msg WDT\n");
}
// disable WDT
void WDT_off(void) {
cli();
wdt_reset();
// clear the WDT reset flag in the status register
MCUSR &= ~(1<<WDRF);
// timed sequence to be able to change the WDT settings afterwards
WDTCSR |= (1<<WDCE) | (1<<WDE);
// disable WDT
WDTCSR = 0x00;
}
// enable WDT
void WDT_on(void) {
// enable the watchdog timer (2s)
wdt_enable(WDTO_2S);
// set watchdog interrupt enable flag
WDTCSR |= (1<<WDIE);
}
void setup()
{
// WDT_off(); -> moved the call to this function to start of the main loop, before init
// clock settings: divide by 8 to get a 1Mhz clock, allows us to set the BOD level to 1.8V (DS p.37)
CLKPR = (1<<CLKPCE);
CLKPR = (1<<CLKPS1) | (1<<CLKPS0);
// load meterid's and metervalues from EEPROM
eeprom_read_block((void*)&measurements, (const void*)&EEPROM_measurements, sizeof(measurements));
// init serial port
beginSerial(4800);
_delay_ms(100);
//LEDPIN=PB5/SCK configured as output pin
DDRB |= (1<<PB5);
// PD2=INT0 and PD3=INT1 configuration
// set as input pin with 20k pull-up enabled
PORTD |= (1<<PD2) | (1<<PD3);
// INT0 and INT1 to trigger an interrupt on a falling edge
EICRA = (1<<ISC01) | (1<<ISC11);
// enable INT0 and INT1 interrupts
EIMSK = (1<<INT0) | (1<<INT1);
#if DBG > 0
// re-use PD4 pin for tracing interrupt times
DDRD |= (1<<DDD4);
#else
// PD4=PCINT20 configuration
// set as input pin with 20k pull-up enabled
PORTD |= (1<<PD4);
//enable pin change interrupt on PCINT20
PCMSK2 |= (1<<PCINT20);
//pin change interrupt enable 2
PCICR |= (1<<PCIE2);
#endif
// analog comparator setup for brown-out detection
// PD7=AIN1 configured by default as input to obtain high impedance
// disable digital input cicuitry on AIN0 and AIN1 pins to reduce leakage current
DIDR1 |= (1<<AIN1D) | (1<<AIN0D);
// comparing AIN1 (Vcc/4.4) to bandgap reference (1.1V)
// bandgap select | AC interrupt enable | AC interrupt on rising edge (DS p.243)
ACSR |= (1<<ACBG) | (1<<ACIE) | (1<<ACIS1) | (1<<ACIS0);
// Timer2 set to CTC mode (DS p.146, 154, 157)
TCCR2A |= 1<<WGM21;
#if DBG > 0
// Toggle pin OC2A=PB3 on compare match
TCCR2A |= 1<<COM2A0;
#endif
// Set PB3 as output pin
DDRB |= (1<<DDB3);
// Timer2 clock prescaler set to 8 => fTOV2 = 1000kHz / 256 / 8 = 488.28Hz (DS p.158)
TCCR2B |= (1<<CS21);
// Enable output compare match interrupt for timer2 (DS p.159)
TIMSK2 |= (1<<OCIE2A);
// Increase sampling frequency to 1250Hz (= 625Hz per channel)
OCR2A = 0x63;
// disable digital input cicuitry on ADCx pins to reduce leakage current
DIDR0 |= (1<<ADC5D) | (1<<ADC4D) | (1<<ADC3D) | (1<<ADC2D) | (1<<ADC1D) | (1<<ADC0D);
// select VBG as reference for ADC
ADMUX |= (1<<REFS1) | (1<<REFS0);
// ADC prescaler set to 8 => 1000kHz / 8 = 125kHz (DS p.258)
ADCSRA |= (1<<ADPS1) | (1<<ADPS0);
// enable ADC and start a first ADC conversion
ADCSRA |= (1<<ADEN) | (1<<ADSC);
//set global interrupt enable in SREG to 1 (DS p.12)
sei();
}
void send(uint8_t msg_type, const struct sensor *measurement, const struct state *aux)
{
uint8_t i;
uint32_t value = 0;
uint32_t ms = 0;
int32_t rest;
uint8_t pulse_count;
char message[60];
switch (msg_type) {
case PULSE:
// blink the green LED
PORTB |= (1<<PB5);
_delay_ms(20);
PORTB &= ~(1<<PB5);
cli();
value = measurement->value;
ms = aux->time;
sei();
strcpy(message, "pls ");
break;
case POWER:
cli();
rest = aux->nano_end - aux->nano_start;
pulse_count = aux->pulse_count_final;
sei();
// Since the AVR has no dedicated floating-point hardware, we need
// to resort to fixed-point calculations for converting nWh/s to W.
// 1W = 10^6/3.6 nWh/s
// value[watt] = 3.6/10^6 * rest[nWh/s]
// value[watt] = 3.6/10^6 * 65536 * (rest[nWh/s] / 65536)
// value[watt] = 3.6/10^6 * 65536 * 262144 / 262144 * (rest[nWh/s] / 65536)
// value[watt] = 61847.53 / 262144 * (rest[nWh/s] / 65536)
// We round the constant down to 61847 to prevent 'underflow' in the
// consecutive else statement.
// The error introduced in the fixed-point rounding equals 8.6*10^-6.
MacU16X16to32(value, (uint16_t)(labs(rest)/65536), 61847);
value /= 262144;
if (rest >= 0)
value += pulse_count*3600;
else
value = pulse_count*3600 - value;
strcpy(message, "pwr ");
break;
}
strcpy(&message[4], measurement->id);
strcpy(&message[36], ":0000000000\n");
i = 46;
do { // generate digits in reverse order
message[i--] = '0' + value % 10; // get next digit
} while ((value /= 10) > 0); // delete it
if ((msg_type == PULSE) && ms) {
strcpy(&message[47], ":0000000000\n");
i = 57;
do { // generate digits in reverse order
message[i--] = '0' + ms % 10; // get next digit
} while ((ms /= 10) > 0); // delete it
}
printString(message);
}
void loop()
{
uint8_t i;
// check whether we have to send out a pls or pwr to the deamon
for (i=0; i<4; i++) {
if (aux[i].pulse == true) {
send(PULSE, (const struct sensor *)&measurements[i], (const struct state *)&aux[i]);
aux[i].pulse = false;
}
if (aux[i].power == true) {
send(POWER, (const struct sensor *)&measurements[i], (const struct state *)&aux[i]);
aux[i].power = false;
}
}
wdt_reset();
}
int main(void)
{
uint8_t i;
WDT_off();
setup();
// insert a startup delay of 20s to prevent interference with redboot
// interrupts are already enabled at this stage
// so the pulses are counted but not sent to the deamon
for (i=0; i<4; i++) _delay_ms(5000);
serialFlush();
printString("\n");
WDT_on();
for (;;) loop();
return 0;
}