- moved

git-svn-id: http://moon:8086/svn/projects/HendiControl@165 fda53097-d464-4ada-af97-ba876c37ca34
2019-03-30 01:04:04 +00:00
parent 54ac3a2834
commit ef0daf1143
8 changed files with 0 additions and 0 deletions
@@ -0,0 +1,100 @@
+/*
+ * uart.c
+ *
+ * Created: 20.02.2019 20:50:13
+ *  Author: jens
+ */ 
+
+#include <stdlib.h>
+#include <avr/io.h>
+
+#include "uart.h"
+
+void uart_init(uint32_t baudrate)
+{
+	uint16_t prescale8 = UART_PRESCALE(baudrate, 8UL);
+	uint16_t prescale16 = UART_PRESCALE(baudrate, 16UL);
+	
+	uint32_t baud8 = ((prescale8+1) * 8);
+	uint32_t baud16 = ((prescale16+1) * 16);
+	
+	uint32_t err8 = abs(baudrate - baud8);
+	uint32_t err16 = abs(baudrate - baud16);
+	
+	uint16_t prescale = prescale16;
+	if (err8 < err16)
+	{
+		prescale = prescale8;
+		
+		// Double UART speed
+		UCSR0A |= 1 << U2X0;
+	}
+	
+	// Set baud rate
+	UBRR0L  = (uint8_t)prescale;
+	UBRR0H = (uint8_t)(prescale >> 8);
+	
+	// Enable receiver and transmitter
+	UCSR0B = (1<<TXEN0)|(1<<RXEN0);
+}
+
+void uart_putc(char c)
+{
+	while((UCSR0A & (1<<UDRE0)) == 0)
+	{
+	}
+	UDR0 = c;
+}
+
+char uart_getc()
+{
+	while ((UCSR0A & (1 << RXC0)) == 0)
+	{
+	}
+	return UDR0;
+}
+
+void uart_puts(char const *str)
+{
+	while(*str)
+	{
+		char c = *(str++);
+		uart_putc(c);
+		if (c == 0x0A)
+		{
+			uart_putc(0x0D);
+		}
+	}
+}
+
+void print_byte(char byte)
+{
+	int i;
+	unsigned char c, nibble;
+
+	for (i=0; i < 2; i++)
+	{
+		nibble = (char)((byte >> 4) & 0xF);
+		byte <<= 4;
+
+		if (nibble < 10)
+		c = nibble + '0';
+		else
+		c = nibble + 'A' - 10;
+
+		uart_putc(c);
+	}
+}
+
+void print_word(uint16_t word)
+{
+	int i;
+	unsigned char c;
+
+	for (i=0; i < 2; i++)
+	{
+		c = (char) (word >> 8);
+		print_byte(c);
+		word <<= 8;
+	}
+}