diff options
Diffstat (limited to 'usb-pcf8573/usb-pcf8573.c')
-rw-r--r-- | usb-pcf8573/usb-pcf8573.c | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/usb-pcf8573/usb-pcf8573.c b/usb-pcf8573/usb-pcf8573.c new file mode 100644 index 0000000..86ed618 --- /dev/null +++ b/usb-pcf8573/usb-pcf8573.c @@ -0,0 +1,130 @@ +/* + * 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(); + } +} |