X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=s88w%2Fs88w-r.c;h=b508b4fa053b48cfda0bc3cb03a3b18ff676c2f5;hb=5d6f425971266accc2e3d1c6de96a0ba031adb8d;hp=15365b43500d117d7a714b6f4cc383b8948575e6;hpb=5fdf476c101b0a3a414519798eb72fcc13825167;p=model-railway-devices.git

diff --git a/s88w/s88w-r.c b/s88w/s88w-r.c
index 15365b4..b508b4f 100644
--- a/s88w/s88w-r.c
+++ b/s88w/s88w-r.c
@@ -37,26 +37,29 @@ void check_input();
 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 clock_high = 0;
+uint8_t rx_buf[7];
+uint8_t rx_fill = 0xFF;
+uint8_t input[128] = { 0 };
+uint8_t latch[128] = { 0 };
+uint8_t output[128] = { 0 };
+uint8_t out_offset = 0;
+uint8_t out_bits = 0;
+uint8_t out_fill = 0;
+volatile uint8_t load_pos = 0xFF;
+volatile uint8_t reset_pos = 0xFF;
+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
+	PCMSK2 = BIT(PCINT19) | BIT(PCINT21);
+	PCICR = BIT(PCIE2);
 
 	serial_init(9600);
 	lcd_init();
@@ -65,53 +68,27 @@ int main()
 
 	while(1)
 	{
-		uint8_t b_pins, d_pins;
-
 		check_input();
 
-		b_pins = PINB;
-		d_pins = PIND;
-
-		if(d_pins&BIT(CLOCK))
+		uint8_t i = load_pos;
+		if(i!=0xFF)
 		{
-			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;
-			}
+			output[i] = latch[i];
+			if(++i>=sizeof(input))
+				i = 0xFF;
+			load_pos = i;
 		}
-		else if(clock_high)
-			clock_high = 0;
 
-		if(d_pins&BIT(RESET))
+		i = reset_pos;
+		if(i!=0xFF)
 		{
-			uint8_t i;
-			for(i=0; i<128; ++i)
-				latch[i] = input[i];
+			latch[i] = input[i];
+			if(++i>=sizeof(input))
+				i = 0xFF;
+			reset_pos = i;
 		}
 
-		if(b_pins&BIT(LCD_DISABLE))
+		if(PINB&BIT(LCD_DISABLE))
 		{
 			if(lcd_enabled)
 			{
@@ -137,11 +114,10 @@ int main()
 
 void check_input()
 {
-	uint8_t c;
 	if(!serial_read_available())
 		return;
 
-	c = serial_read();
+	uint8_t c = serial_read();
 	if(rx_fill==0xFF)
 	{
 		if(c==':')
@@ -151,28 +127,24 @@ void check_input()
 	{
 		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);
+			uint8_t offset = (decode_hex(rx_buf[0])<<8) | (decode_hex(rx_buf[1])<<4) | decode_hex(rx_buf[2]);
+			uint8_t nibbles = (offset&3);
 			offset >>= 2;
 			if(rx_fill>3+nibbles)
 			{
-				for(i=0; i<=nibbles; ++i)
+				for(uint8_t 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];
+					latch[j/2] |= input[j/2];
 				}
 
 				if(lcd_enabled)
 				{
 					lcd_gotoxy(19-offset-nibbles, 0);
-					for(i=0; i<=nibbles; ++i)
+					for(uint8_t i=0; i<=nibbles; ++i)
 						lcd_write(rx_buf[3+i]);
 				}
 			}
@@ -222,3 +194,41 @@ uint8_t decode_hex(uint8_t c)
 	else
 		return 0;
 }
+
+ISR(PCINT2_vect)
+{
+	uint8_t d = PIND;
+	if(d&BIT(CLOCK))
+	{
+		if(!clock_high)
+		{
+			if(d&BIT(LOAD))
+			{
+				out_offset = 0;
+				out_bits = latch[0];
+				out_fill = 8;
+				load_pos = 0;
+			}
+
+			if(out_bits&1)
+				PORTD |= BIT(DATA_OUT);
+			else
+				PORTD &= ~BIT(DATA_OUT);
+
+			out_bits >>= 1;
+			if(!--out_fill)
+			{
+				++out_offset;
+				out_bits = output[out_offset];
+				out_fill = 8;
+			}
+
+			clock_high = 1;
+		}
+	}
+	else
+		clock_high = 0;
+
+	if(d&BIT(RESET))
+		reset_pos = 0;
+}