cleaned up serial completing support for non blocking tx and refactoring formatting functions into a new module 'print'

print.c

@@ -0,0 +1,58 @@
+#include <math.h>
+#include <avr/pgmspace.h>
+#include "serial.h"
+
+void printString(const char *s)
+{
+	while (*s)
+		serial_write(*s++);
+}
+
+// Print a string stored in PGM-memory
+void printPgmString(const char *s)
+{
+  char c;
+	while ((c = pgm_read_byte_near(s++)))
+		serial_write(c);
+}
+
+void printIntegerInBase(unsigned long n, unsigned long base)
+{ 
+	unsigned char buf[8 * sizeof(long)]; // Assumes 8-bit chars. 
+	unsigned long i = 0;
+
+	if (n == 0) {
+		serial_write('0');
+		return;
+	} 
+
+	while (n > 0) {
+		buf[i++] = n % base;
+		n /= base;
+	}
+
+	for (; i > 0; i--)
+		serial_write(buf[i - 1] < 10 ?
+			'0' + buf[i - 1] :
+			'A' + buf[i - 1] - 10);
+}
+
+void printInteger(long n)
+{
+	if (n < 0) {
+		serial_write('-');
+		n = -n;
+	}
+
+	printIntegerInBase(n, 10);
+}
+
+void printFloat(double n)
+{
+  double integer_part, fractional_part;
+  fractional_part = modf(n, &integer_part);
+  printInteger(integer_part);
+  serial_write('.');
+  printInteger(round(fractional_part*1000));
+}
+