#include <avr/interrupt.h>
#include <avr/sleep.h>
#include <util/delay.h>
+#include <util/twi.h>
+#include <avr/eeprom.h>
+#include <avr/wdt.h>
+#include <avr/pgmspace.h>
#include "uart.h"
/*
* 0x0A Voltage LSB
* 0x0B Distance forward2 MSB
* 0x0C Distance forward2 LSB
+ * 0x0D Current MSB
+ * 0x0E Current LSB
*
* 0x15 Distance forward1 MSB (read only)
* 0x16 Distance forward1 LSB (read only)
*/
-#define TWI_ACK TWCR = (1<<TWEA) | (1<<TWINT) | (1<<TWEN) | (1<<TWIE)
-#define TWI_RESET TWCR &= ~((1 << TWSTO) | (1 << TWEN)); TWI_ACK
-#define TWI_NAK TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWIE)
+/**
+ * Nano Pinout
+ * A0 PC0/ADC0
+ * A1 PC1/ADC1
+ * A2 PC2/ADC2
+ * A3 PC3/ADC3
+ * A4 PC4/ADC4
+ * A5 PC5/ADC5
+ * A6 ADC6
+ * A7 ADC7
+ * D0 PD0/RX
+ * D1 PD1/TX
+ * D2 PD2/IND0
+ * D3 PD3/IND1
+ * D4 PD4/T0
+ * D5 PD5/T1
+ * D6 PD6/AIN0
+ * D7 PD7/AIN1
+ * D8 PB0/ICP
+ * D9 PB1/OC1
+ * D10 PB2/SS
+ * D11 PB3/MOSI
+ * D12 PB4/MISO
+ * D13 PB5/SCK
+ */
+
+
+#define TWI_ACK TWCR = (1<<TWINT) | (1<<TWEA) | (1<<TWEN) | (1<<TWIE)
+#define TWI_NAK TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWIE)
+#define TWI_RESET TWCR = (1<<TWINT) | (1<<TWEA) | (1<<TWSTO) | (1<<TWEN) | (1<<TWIE);
static volatile uint8_t ireg=0;
static volatile uint8_t bootloader=0;
static volatile uint8_t start_dist_fwd2=0;
static volatile uint8_t start_dist_bwd=0;
static volatile uint16_t voltage=0;
+static volatile uint16_t current=0;
static volatile uint8_t pind_pre=0;
ISR(TWI_vect)
{
static int16_t tmp16=0;
- switch (TWSR & 0xF8)
+ switch(TW_STATUS)
{
- case 0x60: // start write
+ case TW_SR_SLA_ACK: // start write
TWI_ACK;
ireg = 0;
break;
- case 0x80: // write
+ case TW_SR_DATA_ACK: // write
switch(ireg) {
case 0x00: // register select
ireg = TWDR;
default:
TWI_NAK;
}
- ireg++;
+ if (ireg < 0xff) ireg++;
break;
- case 0xA8: // start read
- case 0xB8: // read
+ case TW_ST_SLA_ACK: // start read
+ case TW_ST_DATA_ACK: // read
switch(ireg) {
case 0x01: // Distance left MSB
tmp16 = dist_left;
TWDR = tmp16;
TWI_ACK;
break;
+ case 0x0D: // Current MSB
+ tmp16 = current;
+ TWDR = tmp16>>8;
+ TWI_ACK;
+ break;
+ case 0x0E: // Current LSB
+ TWDR = tmp16;
+ TWI_ACK;
+ break;
case 0x15: // Distance forward1 MSB
tmp16 = dist_forward1;
TWDR = tmp16>>8;
}
ireg++;
break;
+ case TW_SR_STOP:
+ TWI_ACK;
+ break;
default:
TWI_RESET;
}
}
+/*
+ * zero offset: 0.5V
+ * sensitivity: 133mV/A
+ */
+static unsigned short get_current(void) {
+ double volt = ReadChannel(3)*5.0171; // mV
+ return (volt-517.78)/0.12656; // mA
+}
+
+
ISR(INT0_vect) {
static uint16_t t_start=0;
uint16_t t_now = TCNT1;
// I2C
TWAR = 0x52;
- TWI_RESET;
+ TWI_ACK;
// Timer 1: Normal mode, Top: 0xffff, Prescaler: F_CPU/256=62500Hz
TCCR1A = 0x0;
EICRA = (1 << ISC10) | (1 << ISC00);
PCICR = (1 << PCIE2);
- printf("\r\nStart\r\n");
+ printf_P(PSTR("\r\nStart\r\n"));
set_sleep_mode(SLEEP_MODE_IDLE);
sei();
case 0x09: // voltage
voltage = get_voltage();
break;
+ case 0x0d: // current
+ current = get_current();
+ break;
case 0xff: // Magic reg that starts the bootloader
if (bootloader == 0xa5) {
cli();
- {
- void (*start)(void) = (void*)0x1800;
- start();
- }
+ // write mark to first area in eeprom
+ eeprom_write_byte((uint8_t*)0, 123);
+ eeprom_busy_wait();
+ // Use watchdog to restart
+ wdt_enable(WDTO_15MS);
}
break;
}