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| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,14 @@ | ||
| /* Target configuration */ | ||
| #define F_CPU (16000000L) | ||
| #define JUMP_ADDR (0x00) | ||
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| /* SWUART pin-configuration */ | ||
| #define CONFIG_SWUART_RX_BIT (PB3) | ||
| #define CONFIG_SWUART_RX_PORT (PORTB) | ||
| #define CONFIG_SWUART_RX_PIN (PINB) | ||
| #define CONFIG_SWUART_RX_DIR (DDRB) | ||
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| #define CONFIG_SWUART_TX_BIT (PB4) | ||
| #define CONFIG_SWUART_TX_PORT (PORTB) | ||
| #define CONFIG_SWUART_TX_DIR (DDRB) | ||
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| Original file line number | Diff line number | Diff line change |
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| @@ -0,0 +1,43 @@ | ||
| /* Copyright (C) 2010-2011 Magnus Olsson | ||
| * | ||
| * This file is part of magboot | ||
| * Windnode 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 | ||
| * (at your option) any later version. | ||
| * | ||
| * Windnode 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 magboot. If not, see <http://www.gnu.org/licenses/>. | ||
| */ | ||
| #include <stdint.h> | ||
| #include <avr/io.h> | ||
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| void uart_putc(uint8_t ch) | ||
| { | ||
| loop_until_bit_is_set(UCSR0A, UDRE0); | ||
| UDR0 = ch; | ||
| } | ||
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| uint8_t uart_getc(void) | ||
| { | ||
| uint8_t ch; | ||
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| loop_until_bit_is_set(UCSR0A, RXC0); | ||
| ch = UDR0; | ||
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| return ch; | ||
| } | ||
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| void uart_init() | ||
| { | ||
| UCSR0A = _BV(U2X0); | ||
| UCSR0B = _BV(RXEN0) | _BV(TXEN0); | ||
| UCSR0C = _BV(UCSZ00) | _BV(UCSZ01); | ||
| UBRR0L = (uint8_t)((F_CPU + BAUD_RATE * 4L)/(BAUD_RATE * 8L) - 1); | ||
| } | ||
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| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,127 @@ | ||
| /* Copyright (C) 2010-2011 Magnus Olsson | ||
| * | ||
| * This file is part of magboot | ||
| * Windnode 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 | ||
| * (at your option) any later version. | ||
| * | ||
| * Windnode 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 magboot. If not, see <http://www.gnu.org/licenses/>. | ||
| */ | ||
| #include <avr/io.h> | ||
| #include <avr/interrupt.h> | ||
| #include <stdint.h> | ||
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| #include "uart.h" | ||
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| #define STARTBIT (0) | ||
| #define STOPBIT (1) | ||
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| /* Calculate baudtime using timer pre-scaler 64 */ | ||
| #define BAUDTIME ((F_CPU)/(BAUD_RATE*64l)) | ||
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| #if (BAUDTIME > 255) | ||
| #error Baudrate is too low! | ||
| #endif | ||
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| #if (BAUDTIME < 1) | ||
| #error Baudrate is too high! | ||
| #endif | ||
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| static void __bit_delay(void) | ||
| { | ||
| TCCR0B |= _BV(CS01) | _BV(CS00); /* Timer pre-scaler 64 */ | ||
| while (TCNT0 < BAUDTIME) { /* NOP */ } | ||
| TCCR0B &= ~(_BV(CS01) | _BV(CS00)); | ||
| } | ||
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| static void bit_delay(void) | ||
| { | ||
| TCNT0 = 0; | ||
| __bit_delay(); | ||
| } | ||
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| static void half_bit_delay(void) | ||
| { | ||
| TCNT0 = BAUDTIME/2; | ||
| __bit_delay(); | ||
| } | ||
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| static uint8_t rx_pin(void) | ||
| { | ||
| return (CONFIG_SWUART_RX_PIN & _BV(CONFIG_SWUART_RX_BIT)) != 0; | ||
| } | ||
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| static void tx_pin(uint8_t hi) | ||
| { | ||
| if (hi) | ||
| CONFIG_SWUART_TX_PORT |= _BV(CONFIG_SWUART_TX_BIT); | ||
| else | ||
| CONFIG_SWUART_TX_PORT &= ~(_BV(CONFIG_SWUART_TX_BIT)); | ||
| } | ||
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| /* uart_putc() -- blocking 8N1 transmit */ | ||
| void uart_putc(uint8_t ch) | ||
| { | ||
| uint8_t bit; | ||
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| tx_pin(STARTBIT); | ||
| bit_delay(); | ||
| for (bit = 0; bit < 8; bit++) { | ||
| tx_pin(ch & 0x1); | ||
| ch = ch >> 1; | ||
| bit_delay(); | ||
| } | ||
| tx_pin(STOPBIT); | ||
| bit_delay(); | ||
| } | ||
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| static int __getc(void) | ||
| { | ||
| uint8_t bit; | ||
| uint8_t ch; | ||
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| half_bit_delay(); | ||
| if (rx_pin() != STARTBIT) | ||
| return -1; /* Glitch */ | ||
| bit_delay(); | ||
| for (bit = 0; bit < 8; bit++) { | ||
| ch = ch >> 1; | ||
| if (rx_pin()) | ||
| ch |= 1 << 7; | ||
| bit_delay(); | ||
| } | ||
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| if (rx_pin() != STOPBIT) | ||
| return -2; /* Frame error */ | ||
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| return (int) ch; | ||
| } | ||
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| /* uart_getc() -- blocking 8N1 receive */ | ||
| uint8_t uart_getc(void) | ||
| { | ||
| while (1) { | ||
| int ch; | ||
| while (rx_pin() != STARTBIT) { /* NOP */ } | ||
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| ch = __getc(); | ||
| if (ch >= 0) | ||
| return (uint8_t) ch; | ||
| } | ||
| } | ||
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| void uart_init() | ||
| { | ||
| CONFIG_SWUART_RX_DIR &= ~(_BV(CONFIG_SWUART_RX_BIT)); | ||
| CONFIG_SWUART_RX_PORT |= _BV(CONFIG_SWUART_RX_BIT); | ||
| CONFIG_SWUART_TX_DIR |= _BV(CONFIG_SWUART_TX_BIT); | ||
| tx_pin(STOPBIT); | ||
| } | ||
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