From: Mikko Rasa <tdb@tdb.fi>
Date: Sat, 3 Apr 2010 09:49:02 +0000 (+0000)
Subject: Add a program for serial port control and associated Arduino firmware
X-Git-Url: http://git.tdb.fi/?p=model-railway-devices.git;a=commitdiff_plain;h=fd3352aba49e455947bdcbfccc8a37e165564ba3

Add a program for serial port control and associated Arduino firmware
---

fd3352aba49e455947bdcbfccc8a37e165564ba3
diff --git a/firmware/Makefile b/firmware/Makefile
new file mode 100644
index 0000000..68d6f4c
--- /dev/null
+++ b/firmware/Makefile
@@ -0,0 +1,23 @@
+# $Id$
+
+MCU = atmega328p
+CLOCK = 16000000
+CFLAGS = -Wall -Os -ffunction-sections -fdata-sections -mmcu=$(MCU) -DF_CPU=$(CLOCK)
+LDFLAGS = -Os -Wl,--gc-sections -mmcu=$(MCU)
+
+help:
+	@echo "Targets:"
+	@echo "  %.hex:    Build firmware from %.c"
+	@echo "  upload-%: Upload firmware to AVR"
+
+%.hex: %.elf
+	avr-objcopy -O ihex $< $@
+
+%.elf: %.o
+	avr-gcc $(LDFLAGS) -o $@ $<
+
+%.o: %.c
+	avr-gcc -c $(CFLAGS) -o $@ $<
+
+upload-%: %.hex
+	avrdude -p$(MCU) -cstk500v1 -P/dev/ttyUSB0 -b57600 -D -Uflash:w:$<:i
diff --git a/firmware/ctrl.c b/firmware/ctrl.c
new file mode 100644
index 0000000..523c702
--- /dev/null
+++ b/firmware/ctrl.c
@@ -0,0 +1,228 @@
+/* $Id$
+
+This file is part of the MSP Märklin suite
+Copyright © 2010  Mikkosoft Productions, Mikko Rasa
+Distributed under the GPL
+*/
+
+#include <avr/io.h>
+#include <avr/interrupt.h>
+
+#define BIT(n) (1<<(n))
+#define NOP() __asm__("nop");
+
+uint8_t digits[11] =
+{
+	0x3F,
+	0x06,
+	0x5B,
+	0x4F,
+	0x66,
+	0x6D,
+	0x7D,
+	0x07,
+	0x7F,
+	0x6F,
+	0x40
+};
+
+uint16_t read_input(void);
+uint16_t read_input_filtered(void);
+void write_serial(uint8_t);
+void write_7seg(uint8_t);
+
+uint8_t speed = 0;
+uint16_t funcs = 0;
+volatile uint8_t ticks = 0;
+volatile uint8_t rx_buf[3];
+volatile uint8_t rx_fill = 0;
+
+ISR(TIMER1_COMPA_vect)
+{
+	if(ticks<255)
+		++ticks;
+}
+
+ISR(USART_RX_vect)
+{
+	uint8_t c = UDR0;
+	if(rx_fill==0)
+	{
+		if(c=='A' || c=='S')
+			rx_buf[rx_fill++] = c;
+	}
+	else
+	{
+		rx_buf[rx_fill++] = c;
+		if(rx_buf[0]=='A' && rx_fill==3)
+		{
+			uint8_t n = (rx_buf[1]-'0')*10+(rx_buf[2]-'0');
+			write_7seg(n/10);
+			write_7seg(n%10);
+			rx_fill = 0;
+		}
+		else if(rx_buf[0]=='S' && rx_fill==3)
+		{
+			speed = (rx_buf[1]-'0')*10+(rx_buf[2]-'0');
+			rx_fill = 0;
+		}
+	}
+}
+
+int main()
+{
+	uint16_t state = 0;
+
+	DDRD = 0x02;   // 00000010
+	PORTD = 0xFC;  // 11111100
+	DDRB = 0x3F;   // 00111111
+	PORTB = 0x0F;  // 00001111
+
+	write_7seg(10);
+	write_7seg(10);
+
+	// 9600 baud, 8N1
+	UBRR0H = 0;
+	UBRR0L = 103;
+	UCSR0C = BIT(UCSZ00) | BIT(UCSZ01);
+	UCSR0B = BIT(RXEN0) | BIT(TXEN0) | BIT(RXCIE0);
+
+	TCCR1A = 0;
+	TCCR1B = BIT(WGM12) | BIT(CS12);
+	OCR1AH = 24;
+	OCR1AL = 106;
+	TIMSK1 = BIT(OCIE1A);
+
+	sei();
+
+	while(1)
+	{
+		uint16_t toggled;
+		uint8_t i;
+		uint16_t input;
+
+		input = read_input_filtered();
+		input ^= 0xFFFC;
+
+		toggled = state^input;
+		state = input;
+
+		if((toggled&3)==2 && (state&1))
+		{
+			uint8_t action = 0;
+			if(state&2)
+			{
+				if(speed<14)
+				{
+					++speed;
+					action = 1;
+				}
+			}
+			else
+			{
+				if(speed>0)
+				{
+					--speed;
+					action = 1;
+				}
+				else if(ticks>10)
+					action = 2;
+			}
+
+			if(action==1)
+			{
+				write_serial('S');
+				write_serial('0'+speed/10);
+				write_serial('0'+speed%10);
+			}
+			else if(action==2)
+				write_serial('R');
+
+			ticks = 0;
+		}
+
+		for(i=0; i<14; ++i)
+		{
+			uint16_t bit = 4<<i;
+			if(toggled&~state&bit)
+			{
+				if(i==0)
+					write_serial('N');
+				else if(i==1)
+					write_serial('P');
+				else
+				{
+					uint8_t f = i-2;
+					uint16_t fbit = 1<<f;
+					funcs ^= fbit;
+					write_serial((funcs&fbit) ? 'H' : 'L');
+					write_serial('0'+f);
+				}
+			}
+		}
+	}
+}
+
+uint16_t read_input(void)
+{
+	uint8_t row;
+	uint16_t input = 0;
+
+	for(row=0; row<4; ++row)
+	{
+		uint8_t pins;
+
+		PORTB = (PORTB|0x0F)&~(1<<row);
+		NOP();
+		NOP();
+		NOP();
+		NOP();
+		NOP();
+		NOP();
+		pins = PIND>>2;
+		input |= pins&3;
+		input |= (pins&0x3C)<<(row*4);
+	}
+
+	return input;
+}
+
+uint16_t read_input_filtered(void)
+{
+	uint16_t valid = 0xFFFF;
+	uint16_t prev;
+	uint16_t input;
+	uint8_t i;
+
+	prev = read_input();
+	for(i=0; i<20; ++i)
+	{
+		input = read_input();
+		valid &= ~(input^prev);
+		prev = input;
+	}
+
+	return input&valid;
+}
+
+void write_serial(uint8_t c)
+{
+	while(!(UCSR0A&(1<<UDRE0))) ;
+	UDR0 = c;
+}
+
+void write_7seg(uint8_t n)
+{
+	uint8_t segs = ~digits[n];
+	uint8_t i;
+	for(i=0; i<8; ++i)
+	{
+		PORTB &= ~0x20;
+		if(segs&0x80)
+			PORTB |= 0x10;
+		else
+			PORTB &= ~0x10;
+		PORTB |= 0x20;
+		segs <<= 1;
+	}
+}