OBJCOPY=avr-objcopy
CFLAGS=-g -mmcu=$(MCU) -Wall -Wstrict-prototypes -Os -mcall-prologues
+OBJS = ao-blink.o ao-switch.o ao-uart.o ao-bringup.o
+
all: ao-blink.hex ao-switch.hex ao-uart.hex
ao-blink.hex: ao-blink
avr-size ao-uart
$(OBJCOPY) -R .eeprom -O ihex ao-uart $@
-ao-uart: ao-uart.o
- $(CC) $(CFLAGS) -o $@ ao-uart.o
+ao-uart: ao-uart.o ao-bringup.o
+ $(CC) $(CFLAGS) -o $@ ao-uart.o ao-bringup.o
ao-uart.s: ao-uart.c
$(CC) $(CFLAGS) -S -o $@ ao-uart.c
+$(OBJS): ao-bringup.h
+
load-blink: ao-blink.hex
$(LOADCMD) $(LOADARG)ao-blink.hex
--- /dev/null
+/*
+ * Copyright © 2011 Keith Packard <keithp@keithp.com>
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include "ao-bringup.h"
+
+static void
+clock_init(void)
+{
+ /* disable RC clock */
+ CLKSEL0 &= ~(1 << RCE);
+
+ /* Disable PLL */
+ PLLCSR &= ~(1 << PLLE);
+
+ /* Enable external clock */
+ CLKSEL0 |= (1 << EXTE);
+
+ /* wait for external clock to be ready */
+ while ((CLKSTA & (1 << EXTON)) == 0)
+ ;
+
+ /* select external clock */
+ CLKSEL0 |= (1 << CLKS);
+
+ /* Disable the clock prescaler */
+ cli();
+ CLKPR = (1 << CLKPCE);
+ CLKPR = 0;
+ sei();
+
+ /* Set up the PLL to use the crystal */
+
+ /* Use primary system clock as PLL source */
+ PLLFRQ = ((0 << PINMUX) | /* Use primary clock */
+ (0 << PLLUSB) | /* No divide by 2 for USB */
+ (0 << PLLTM0) | /* Disable high speed timer */
+ (0x4 << PDIV0)); /* 48MHz PLL clock */
+
+ /* Set the frequency of the crystal */
+#if TEENSY
+ PLLCSR |= (1 << PINDIV); /* For 16MHz crystal on Teensy board */
+#else
+ PLLCSR &= ~(1 << PINDIV); /* For 8MHz crystal on TeleScience board */
+#endif
+
+ /* Enable the PLL */
+ PLLCSR |= (1 << PLLE);
+ while (!(PLLCSR & (1 << PLOCK)))
+ ;
+}
+
+void
+uart_send(char c)
+{
+ LEDPORT ^= (1 << LEDOUT);
+ loop_until_bit_is_set(UCSR1A, UDRE1);
+ UDR1 = c;
+}
+
+int
+uart_put(char c, FILE *stream)
+{
+ if (c == '\n')
+ uart_send('\r');
+ uart_send(c);
+ return 0;
+}
+
+int
+uart_get(FILE *stream)
+{
+ loop_until_bit_is_set(UCSR1A, RXC1);
+ return (int) UDR1 & 0xff;
+}
+
+void
+uart_init(uint16_t baud)
+{
+ PRR1 &= ~(1 << PRUSART1);
+ UBRR1L = baud;
+ UBRR1H = baud >> 8;
+ UCSR1A = 0;
+ UCSR1B = ((1 << RXEN1) | /* Enable receiver */
+ (1 << TXEN1)); /* Enable transmitter */
+ UCSR1C = ((0 << UMSEL10) | /* Asynchronous mode */
+ (0 << UPM10) | /* No parity */
+ (0 << USBS1) | /* 1 stop bit */
+ (3 << UCSZ10) | /* 8 bit characters */
+ (0 << UCPOL1)); /* MBZ for async mode */
+}
+
+static FILE mystdout = FDEV_SETUP_STREAM(uart_put, NULL, _FDEV_SETUP_WRITE);
+
+static FILE mystdin = FDEV_SETUP_STREAM(NULL, uart_get, _FDEV_SETUP_READ);
+
+void ao_bringup_init(void)
+{
+ clock_init();
+ uart_init(F_CPU / (16UL * 9600UL) - 1);
+
+ stdout = &mystdout;
+ stdin = &mystdin;
+
+ LEDDDR |= (1 << LEDDDRPIN);
+}
--- /dev/null
+/*
+ * Copyright © 2011 Keith Packard <keithp@keithp.com>
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#ifndef _AO_BRINGUP_
+#define _AO_BRINGUP_
+
+#include <stdio.h>
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#define TEENSY 1
+#if TEENSY
+#define F_CPU 16000000UL // 16 MHz
+#else
+#define F_CPU 8000000UL // 8 MHz
+#endif
+#include <util/delay.h>
+
+#define LEDOUT PORTB7
+#define LEDPORT PORTB
+#define LEDDDR DDRB
+#define LEDDDRPIN DD7
+
+void ao_bringup_init(void);
+
+#endif
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*/
-#include <avr/io.h>
-#include <avr/interrupt.h>
-#define TEENSY 1
-#if TEENSY
-#define F_CPU 16000000UL // 16 MHz
-#else
-#define F_CPU 8000000UL // 8 MHz
-#endif
-#include <util/delay.h>
-
-#define LEDOUT PORTB7
-#define LEDPORT PORTB
-#define LEDDDR DDRB
-#define LEDDDRPIN DD7
-
-static void
-timer1_init(void)
-{
- TCCR1A = ((0 << WGM11) | /* CTC mode, OCR1A */
- (0 << WGM10)); /* CTC mode, OCR1A */
- TCCR1B = ((0 << ICNC1) | /* no input capture noise canceler */
- (0 << ICES1) | /* input capture on falling edge (don't care) */
- (0 << WGM13) | /* CTC mode, OCR1A */
- (1 << WGM12) | /* CTC mode, OCR1A */
- (3 << CS10)); /* clk/64 from prescaler */
-
-#if TEENSY
- OCR1A = 2500; /* 16MHz clock */
-#else
- OCR1A = 1250; /* 8MHz clock */
-#endif
-
- TIMSK1 = (1 << OCIE1A); /* Interrupt on compare match */
-}
-
-static void
-clock_init(void)
-{
- /* disable RC clock */
- CLKSEL0 &= ~(1 << RCE);
-
- /* Disable PLL */
- PLLCSR &= ~(1 << PLLE);
-
- /* Enable external clock */
- CLKSEL0 |= (1 << EXTE);
-
- /* wait for external clock to be ready */
- while ((CLKSTA & (1 << EXTON)) == 0)
- ;
-
- /* select external clock */
- CLKSEL0 |= (1 << CLKS);
-
- /* Disable the clock prescaler */
- cli();
- CLKPR = (1 << CLKPCE);
- CLKPR = 0;
- sei();
-
- /* Set up the PLL to use the crystal */
-
- /* Use primary system clock as PLL source */
- PLLFRQ = ((0 << PINMUX) | /* Use primary clock */
- (0 << PLLUSB) | /* No divide by 2 for USB */
- (0 << PLLTM0) | /* Disable high speed timer */
- (0x4 << PDIV0)); /* 48MHz PLL clock */
-
- /* Set the frequency of the crystal */
-#if TEENSY
- PLLCSR |= (1 << PINDIV); /* For 16MHz crystal on Teensy board */
-#else
- PLLCSR &= ~(1 << PINDIV); /* For 8MHz crystal on TeleScience board */
-#endif
-
- /* Enable the PLL */
- PLLCSR |= (1 << PLLE);
- while (!(PLLCSR & (1 << PLOCK)))
- ;
-}
-
-void
-uart_send(char data)
-{
- while (!(UCSR1A & (1 << UDRE1)))
- ;
- UDR1 = data;
-}
-
-void
-uart_init(uint16_t baud)
-{
- PRR1 &= ~(1 << PRUSART1);
- UBRR1L = baud;
- UBRR1H = baud >> 8;
- UCSR1A = 0;
- UCSR1B = ((1 << RXEN1) | /* Enable receiver */
- (1 << TXEN1)); /* Enable transmitter */
- UCSR1C = ((0 << UMSEL10) | /* Asynchronous mode */
- (0 << UPM10) | /* No parity */
- (0 << USBS1) | /* 1 stop bit */
- (3 << UCSZ10) | /* 8 bit characters */
- (0 << UCPOL1)); /* MBZ for async mode */
-}
+#include "ao-bringup.h"
int main(void)
{
- clock_init();
- timer1_init();
- uart_init(832);
-
- LEDDDR |= (1 << LEDDDRPIN);
+ ao_bringup_init();
for (;;) {
- LEDPORT ^= (1 << LEDOUT);
- uart_send('H');
+ printf("Hello, world\n");
}
}
projects / fw / altos / commitdiff