X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=s88w%2Fs88w-r.c;fp=s88w%2Fs88w-r.c;h=019897483cc63b2b36dc1f6cc79cf151e4064f72;hb=9c37d18b9c70fdb70dfec453398c4649e9e57586;hp=0000000000000000000000000000000000000000;hpb=49b6b6ad84ec47b4f9eb9ef131975cc5b72372a2;p=model-railway-devices.git

diff --git a/s88w/s88w-r.c b/s88w/s88w-r.c
new file mode 100644
index 0000000..0198974
--- /dev/null
+++ b/s88w/s88w-r.c
@@ -0,0 +1,219 @@
+/*
+Firmware for wireless S88 receiver module
+
+S88 pinout:
+1 - DATA
+2 - GND
+3 - CLOCK
+4 - LOAD
+5 - RESET
+6 - POWER
+
+ATMega pinout:
+D0 - serial RX
+D1 - serial TX
+D2 - S88 DATA
+D3 - S88 CLOCK
+D4 - S88 LOAD
+D5 - S88 RESET
+*/
+
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include "lcd.h"
+#include "serial.h"
+#include "delay.h"
+
+#define DATA_OUT PORTD2
+#define CLOCK    PIND3
+#define LOAD     PIND4
+#define RESET    PIND5
+
+#define LCD_DISABLE PINB4
+
+#define BIT(n)   (1<<(n))
+
+void receive(uint8_t);
+uint8_t hexdigit(uint8_t);
+uint8_t decode_hex(uint8_t);
+
+volatile uint8_t rx_buf[7];
+volatile uint8_t rx_fill = 0xFF;
+volatile uint8_t input[128] = { 0 };
+volatile uint8_t latch[128] = { 0 };
+volatile uint8_t lcd_enabled = 0;
+uint8_t log_row = 0;
+uint8_t log_col = 0;
+
+int main()
+{
+	uint8_t clock_high = 0;
+	uint8_t bits = 0;
+	uint8_t n_bits = 8;
+	uint8_t offset = 0;
+	uint8_t i;
+
+	DDRD = 0x06;   // 00000110
+	PORTD = 0xC0;  // 11000000
+	DDRB = 0x20;   // 00100000
+	PORTB = 0x1F;  // 00011111
+
+	serial_init(9600);
+	lcd_init();
+
+	sei();
+
+	while(1)
+	{
+		uint8_t b_pins, d_pins;
+
+		b_pins = PINB;
+		d_pins = PIND;
+
+		if(d_pins&BIT(CLOCK))
+		{
+			if(!clock_high)
+			{
+				if(d_pins&BIT(LOAD))
+				{
+					offset = 0;
+					bits = latch[0];
+					n_bits = 8;
+				}
+				else
+				{
+					bits >>= 1;
+					if(!--n_bits)
+					{
+						++offset;
+						bits = latch[offset];
+						n_bits = 8;
+					}
+				}
+
+				if(bits&1)
+					PORTD |= BIT(DATA_OUT);
+				else
+					PORTD &= ~BIT(DATA_OUT);
+
+				clock_high = 1;
+			}
+		}
+		else if(clock_high)
+			clock_high = 0;
+
+		if(d_pins&BIT(RESET))
+		{
+			uint8_t i;
+			for(i=0; i<128; ++i)
+				latch[i] = input[i];
+		}
+
+		if(b_pins&BIT(LCD_DISABLE))
+		{
+			if(lcd_enabled)
+			{
+				lcd_enabled = 0;
+
+				lcd_clear();
+			}
+		}
+		else if(!lcd_enabled)
+		{
+			lcd_enabled = 1;
+			log_row = 0;
+			log_col = 0;
+
+			lcd_clear();
+			for(i=0; i<20; ++i)
+				lcd_write(hexdigit(input[9-i/2]>>(4-i%2*4)));
+			lcd_gotoxy(0, 1);
+			lcd_write(255);
+		}
+	}
+}
+
+void receive(uint8_t c)
+{
+	if(rx_fill==0xFF)
+	{
+		if(c==':')
+			rx_fill = 0;
+	}
+	else if(c=='.')
+	{
+		if(rx_fill>=4)
+		{
+			uint16_t offset;
+			uint8_t nibbles;
+			uint8_t i;
+
+			offset = (decode_hex(rx_buf[0])<<8) | (decode_hex(rx_buf[1])<<4) | decode_hex(rx_buf[2]);
+			nibbles = (offset&3);
+			offset >>= 2;
+			if(rx_fill>3+nibbles)
+			{
+				for(i=0; i<=nibbles; ++i)
+				{
+					uint16_t j = offset+nibbles-i;
+					uint8_t shift = 4*(j&1);
+					uint8_t bits = decode_hex(rx_buf[3+i]);
+					input[j/2] = (input[j/2]&~(0xF<<shift)) | (bits<<shift);
+					latch[j/2] = input[j/2];
+				}
+
+				if(lcd_enabled)
+				{
+					lcd_gotoxy(19-offset-nibbles, 0);
+					for(i=0; i<=nibbles; ++i)
+						lcd_write(rx_buf[3+i]);
+				}
+			}
+		}
+		rx_fill = 0xFF;
+	}
+	else
+	{
+		if(rx_fill<sizeof(rx_buf))
+			rx_buf[rx_fill++] = c;
+		else
+			rx_fill = 0xFF;
+	}
+
+	if(lcd_enabled)
+	{
+		lcd_gotoxy(log_col, 1+log_row);
+		lcd_write(c);
+		++log_col;
+		if(log_col>=20)
+		{
+			log_col = 0;
+			++log_row;
+			if(log_row>=3)
+				log_row = 0;
+			lcd_gotoxy(log_col, 1+log_row);
+		}
+		lcd_write(255);
+	}
+}
+
+SERIAL_SET_CALLBACK(receive)
+
+uint8_t hexdigit(uint8_t n)
+{
+	n &= 0xF;
+	if(n<10)
+		return '0'+n;
+	else
+		return 'A'+(n-0xA);
+}
+
+uint8_t decode_hex(uint8_t c)
+{
+	if(c>='0' && c<='9')
+		return c-'0';
+	else if(c>='A' && c<='F')
+		return 0xA+(c-'A');
+	else
+		return 0;
+}