+ track node firmware

locodoco/firmware/track_node/Makefile

@@ -0,0 +1,86 @@
+OBJ = main.o 
+
+# hardware revision (only v1 yet)
+HWREF         := 1
+
+# Default values
+MCU_TARGET    ?= attiny45
+OUT           ?= track-node-hwr$(HWREF)-$(MCU_TARGET)
+MCU_CC        ?= avr-gcc
+MCU_AS	      ?= avr-as
+OPTIMIZE      ?= -Os
+WARNINGS      ?= -Wall -Winline
+DEFS          ?= -DF_CPU=8000000 -DHWREF=$(HWREF) -DMCU=$(MCU_TARGET)
+CFLAGS        += -mmcu=$(MCU_TARGET) $(OPTIMIZE) $(WARNINGS) $(DEFS) -I.
+ASFLAGS	      += -mmcu=avr5
+LDFLAGS        = -Wl,-Map,$(OUT).map
+
+# External Tools
+OBJCOPY       ?= avr-objcopy
+OBJDUMP       ?= avr-objdump
+FLASHCMD      ?= avrdude -c usbasp -p $(MCU_TARGET) -U flash:w:$(OUT).hex
+ERASECMD      ?= avrdude -c usbasp -p $(MCU_TARGET) -e
+
+#############################################################################
+# Rules
+all: $(OUT).elf lst text eeprom
+
+clean:
+	rm -rf $(OUT) *.o *.lst *.map *.hex *.bin *.srec
+	rm -rf *.srec $(OUT).elf
+
+flash: $(OUT).hex
+	$(ERASECMD)
+	$(FLASHCMD)
+
+
+
+#############################################################################
+# Building Rules 
+$(OUT).elf: $(OBJ)
+	$(MCU_CC) $(CFLAGS) $(LDFLAGS) -o $@ $^ $(LIBS)
+
+%.o: %.c
+	$(MCU_CC) $(CFLAGS) -c $< -o $@ 
+
+%.o: %.S
+	$(MCU_AS) $(ASFLAGS) -o $@ $<
+
+lst: $(OUT).lst
+
+%.lst: %.elf
+	$(OBJDUMP) -h -S $< > $@
+
+# Rules for building the .text rom images
+text: hex bin srec
+
+hex:  $(OUT).hex
+bin:  $(OUT).bin
+srec: $(OUT).srec
+
+%.hex: %.elf
+	$(OBJCOPY) -j .text -j .data -O ihex $< $@
+
+%.srec: %.elf
+	$(OBJCOPY) -j .text -j .data -O srec $< $@
+
+%.bin: %.elf
+	$(OBJCOPY) -j .text -j .data -O binary $< $@
+
+# Rules for building the .eeprom rom images
+
+eeprom: ehex ebin esrec
+
+ehex:  $(OUT)_eeprom.hex
+ebin:  $(OUT)_eeprom.bin
+esrec: $(OUT)_eeprom.srec
+
+%_eeprom.hex: %.elf
+	$(OBJCOPY) -j .eeprom --change-section-lma .eeprom=0 -O ihex $< $@
+
+%_eeprom.srec: %.elf
+	$(OBJCOPY) -j .eeprom --change-section-lma .eeprom=0 -O srec $< $@
+
+%_eeprom.bin: %.elf
+	$(OBJCOPY) -j .eeprom --change-section-lma .eeprom=0 -O binary $< $@
+

locodoco/firmware/track_node/config.h

@@ -0,0 +1,60 @@
+#include <avr/io.h>
+#include <avr/interrupt.h>
+
+#pragma once
+
+#if \
+	defined(__AVR_ATtiny13__) || \
+	defined(__AVR_ATtiny13A__)
+	/*
+		tiny13 support *NOT TESTED YET*
+	*/
+	#error wtf
+	#define TIMER_INIT \
+		TCCR0A = _BV(WGM1); /* clear on compare match */ \
+		OCRA = 125; /* 4.8M / 38400 -> 125 cycles/bit */ \
+		TCCR0B = (_BV(CS00)); /* clk/1;  */ \
+		TIMSK0 = _BV(OCIE0A) /* OCR0A int */
+
+	#define BIT_ISR ISR(TIMER0_COMPA_vect)
+
+	#define PIN_LED0  _BV(PB0)
+	#define DDR_LED0  DDRB
+	#define PORT_LED0 PORTB
+
+	#define PRESCALER_INIT /* system clock prescaler */ \
+		CLKPR = _BV(CLKPCE); \
+		CLKPR = _BV(CLKPS0) /* /2 */
+
+#elif \
+	defined(__AVR_ATtiny25__) || \
+	defined(__AVR_ATtiny45__) || \
+	defined(__AVR_ATtiny85__)
+
+	#define TIMER_INIT \
+		TCCR0A = _BV(WGM01); /* clear on compare match */ \
+		OCR0A = 52; /* 2M / 38400 -> 52.083 cycles/bit */ \
+		TCCR0B = (_BV(CS00)); /* clk/1;  */ \
+		TIMSK = _BV(OCIE0A) /* OCR0A int */
+
+	#define BIT_ISR ISR(TIMER0_COMPA_vect)
+
+	#define PIN_LED0  _BV(PB0)
+	#define DDR_LED0  DDRB
+	#define PORT_LED0 PORTB
+
+	#define PRESCALER_INIT /* system clock prescaler */ \
+		CLKPR = _BV(CLKPCE); \
+		CLKPR = _BV(CLKPS1) /* / 4 */
+#else
+	#error "can't find valid config for your mcu. please edit config.h"
+#endif
+
+/* general config */
+
+#define OUT0_0 PORT_LED0 &= ~(PIN_LED0)
+#define OUT0_1 PORT_LED0 |= PIN_LED0
+#define OUT0_INIT DDR_LED0 |= PIN_LED0
+
+/* additional stop bits at the end of each transmission */
+#define NUM_STOPBITS 8

locodoco/firmware/track_node/main.c

@@ -0,0 +1,102 @@
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include <avr/eeprom.h>
+#include <util/crc16.h>
+
+#include "config.h"
+
+volatile static uint8_t tx_seq[16];
+volatile static uint8_t num_bytes = 0;
+
+BIT_ISR
+{
+	static uint8_t bytec = 0;
+	static uint8_t mask = 0xff;
+
+	if (!mask) /* stop bit(s) */
+	{
+
+		if (bytec < num_bytes)
+		{
+			mask = 0xff; /* start bit */
+			asm volatile("nop"); /* shortest code path - add some nops */
+			asm volatile("nop");
+			OUT0_1;
+			return;
+		}
+
+		OUT0_1; /* intentionally twice to make delays close to symmetric */
+
+		/* send extra stop bits at the end of the transmission */
+		if (bytec < num_bytes + NUM_STOPBITS)
+			return;
+
+		/* start over */
+		mask = 0xff;
+		bytec = 0;
+	} else if (mask == 0xff) /* start bit */
+	{
+		bytec++;
+		mask = 0x80;
+		OUT0_0;
+	} else /* data bits */
+	{
+		if (tx_seq[bytec] & mask)
+		{
+			OUT0_1;
+		} else
+		{
+			OUT0_0;
+		}
+		mask >>= 1;
+	}
+}
+
+/* read eeprom, fill tx_seq
+ */
+void eeprom_init()
+{
+	uint16_t *crcptr;
+	uint8_t i;
+
+	eeprom_busy_wait();
+	num_bytes = eeprom_read_byte ((const void*) 0x00);
+
+	if (num_bytes > sizeof(tx_seq) - 2)
+	{
+		num_bytes = sizeof (tx_seq) - 2;
+		tx_seq[0] = 'E';
+		tx_seq[1] = 'S';
+		tx_seq[2] = 'I';
+		tx_seq[3] = 'Z';
+		tx_seq[4] = 'E';
+		return; /* unprogrammed */
+	}
+	eeprom_busy_wait();
+	eeprom_read_block ((void*) &tx_seq[0], (const void*) 0x01, num_bytes);
+
+	/* calc & gen crc */
+	crcptr = (uint16_t *) &tx_seq[num_bytes];
+	*crcptr = 0x00;
+
+	for (i=0;i<num_bytes;i++)
+	{
+		*crcptr = _crc16_update (*crcptr, tx_seq[i]);
+	}
+
+	num_bytes += 2;
+}
+
+int main ()
+{
+	eeprom_init();
+	PRESCALER_INIT;
+	OUT0_INIT;
+	TIMER_INIT;
+	sei();
+
+	while (23)
+	{
+
+	}
+}