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/*
* spreadspace avr utils
*
*
* Copyright (C) 2013-2019 Christian Pointner <equinox@spreadspace.org>
*
* This file is part of spreadspace avr utils.
*
* spreadspace avr utils 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
* any later version.
*
* spreadspace avr utils 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 spreadspace avr utils. If not, see <http://www.gnu.org/licenses/>.
*/
#include <avr/io.h>
#include <avr/wdt.h>
#include <avr/interrupt.h>
#include <avr/power.h>
#include <stdio.h>
#include "util.h"
#include "led.h"
#include "usbio.h"
#include <LUFA/Drivers/Peripheral/TWI.h>
#define RTC_SLAVE_ADDR 0xD0
char* i2c_error_to_string(uint8_t err) {
switch(err) {
case TWI_ERROR_NoError: return "success";
case TWI_ERROR_BusFault: return "bus-fault";
case TWI_ERROR_BusCaptureTimeout: return "bus capture timeout";
case TWI_ERROR_SlaveResponseTimeout: return "slave response timeout";
case TWI_ERROR_SlaveNotReady: return "slave not ready";
case TWI_ERROR_SlaveNAK: return "slave NAK";
}
return "unknown";
}
void i2c_init(void)
{
TWI_Init(TWI_BIT_PRESCALE_1, TWI_BITLENGTH_FROM_FREQ(1, 100000));
}
void get_time(void)
{
uint8_t err = TWI_StartTransmission(RTC_SLAVE_ADDR | TWI_ADDRESS_WRITE, 100);
if(err != TWI_ERROR_NoError) {
printf("I²C start failed: %s\r\n", i2c_error_to_string(err));
return;
}
err = TWI_SendByte(0x00);
if(err != TWI_ERROR_NoError)
goto i2c_error;
err = TWI_StartTransmission(RTC_SLAVE_ADDR | TWI_ADDRESS_READ, 10);
if(err != TWI_ERROR_NoError)
goto i2c_error;
uint8_t time[4];
for(int i = 0; i < sizeof(time); ++i) {
time[i] = 0xFF;
err = TWI_ReceiveByte(&(time[i]), (i+1 == sizeof(time)) ? true : false);
if(err != TWI_ERROR_NoError)
goto i2c_error;
}
TWI_StopTransmission();
for(int i = 0; i < sizeof(time); ++i) {
printf("%s0x%02X%s", ((i==0) ? "" : " "), time[i], (i+1 == sizeof(time)) ? "\r\n" : "");
}
return;
i2c_error:
TWI_StopTransmission();
printf("I2C error: %s\r\n", i2c_error_to_string(err));
return;
}
void handle_cmd(uint8_t cmd)
{
switch(cmd) {
case '0': led_off(); printf("ok\r\n"); break;
case '1': led_on(); printf("ok\r\n"); break;
case 't': get_time(); break;
case 'r': reset2bootloader(); break;
default: printf("error\r\n"); return;
}
}
int main(void)
{
MCUSR &= ~(1 << WDRF);
wdt_disable();
cpu_init();
jtag_disable();
led_init();
usbio_init();
i2c_init();
sei();
led_on();
for(;;) {
int16_t BytesReceived = usbio_bytes_received();
while(BytesReceived > 0) {
int ReceivedByte = fgetc(stdin);
if(ReceivedByte != EOF) {
handle_cmd(ReceivedByte);
}
BytesReceived--;
}
usbio_task();
}
}
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