rename

firmware/usart.cpp

@@ -0,0 +1,130 @@
+#include "usart.h"
+
+void USART::init()
+{
+	UCSR0A = _BV(U2X0);
+	
+	UCSR0B = _BV(RXEN0) | _BV(TXEN0);
+
+	// Einstellen des Datenformats: 8 Datenbits, 1 Stoppbit
+	UCSR0C = _BV(UCSZ00) |_BV(UCSZ01);// (1<<URSEL0)|(1<<UCSZ10)|(1<<UCSZ00);
+
+	// setze Baudrate
+	UBRR0H = (((F_CPU / (8UL * BAUDRATE))-1) >> 8) & 0xFF;
+	UBRR0L =  ((F_CPU / (8UL * BAUDRATE))-1) & 0xFF;
+
+}
+
+void USART::flush()
+{
+	uint8_t dummy;
+	do
+	{
+		dummy = UDR0;
+		_delay_us((1000000 / BAUDRATE) * 16); // Warte Übertragungszeit von 16 Bit ab
+	}
+	while (UCSR0A & (1<<RXC0));
+
+	if(dummy) // taeusche dummy Verwendung vor
+		return;
+}
+
+void USART::writeByte(uint8_t b)
+{
+	while (!(UCSR0A & (1<<UDRE0)));
+	UDR0 = b;
+
+	//while(!(UCSR0A & _BV(TXC0)));
+}
+
+
+void USART::writeInt(uint16_t v)
+{
+
+
+	while (!(UCSR0A & (1<<UDRE0)));
+	UDR0 = v & 0xFF;
+	
+	v >>= 8;
+	while (!(UCSR0A & (1<<UDRE0)));
+	UDR0 = v & 0xFF;
+
+	//while(!(UCSR0A & _BV(TXC0)));
+}
+
+void USART::writeStr(const char* str, uint8_t len)
+{
+	writeByte(len);
+	while(len--)
+		writeByte(*str++);
+}
+
+uint8_t USART::writeBlock(uint8_t* ptr, uint8_t len)
+{
+	writeByte(len);
+
+	uint8_t crc = 0;
+	while(len--)
+    {
+		writeByte(*ptr);
+		crc ^= *ptr++;
+		for (uint8_t i = 0; i < 8; i++)
+		{
+			if (crc & 1)
+				crc ^= CRC7_POLY;
+			crc >>= 1;
+		}
+	}
+
+	writeByte(crc);
+
+	return readByte();
+}
+
+uint8_t USART::readByte()
+{
+	while (!(UCSR0A & (1<<RXC0)));
+    return UDR0;
+}
+
+uint16_t USART::readInt()
+{
+	uint16_t v = readByte();
+	v |= readByte() << 8;
+	return v;
+}
+
+void USART::readBlock(uint8_t* ptr, uint8_t offset)
+{
+	ptr += offset;
+	uint8_t crc;
+	do
+	{
+		crc = 0;
+		uint8_t len = readByte();
+		if(len > MAX_BLOCK_SIZE)
+			len = 0;
+
+		for(uint8_t k = 0; k <= len; k++) // len + 1 Durchgänge (+ crc)
+		{
+			uint8_t next = readByte();
+
+			crc ^= next;
+			for (uint8_t i = 0; i < 8; i++)
+			{
+				if (crc & 1)
+					crc ^= CRC7_POLY;
+				crc >>= 1;
+			}
+
+			if(k < len)
+				ptr[k] = next;
+		}
+
+		
+		flush(); // leere Eingangspuffer
+		
+		writeByte(crc == 0 ? MSG_OK : MSG_FAIL);
+	}
+	while(crc != 0);
+}