Started following some tutorial on att85 usi. Downloaded example code from make avr book.

Make AVR Examples/Chapter09_Introduction-to-Timer-Counter-Hardware/reactionTimer/support.c

@@ -0,0 +1,92 @@
+
+#include "support.h"
+
+void printMilliseconds(uint16_t value) {
+  /* Given a value in milliseconds, prints out how many seconds
+     you took over the serial port.  Does ascii conversion, prints
+     decimal point, and drops extra leading zeros.
+   */
+  uint8_t digit;
+
+  printString("\r\nYou took ");
+                                               /* add up ten-thousands */
+  digit = 0;
+  while (value >= 10000) {
+    digit++;
+    value -= 10000;
+  }
+  if (digit) {
+    transmitByte('0' + digit);
+  }
+                                                   /* add up thousands */
+  digit = 0;
+  while (value >= 1000) {
+    digit++;
+    value -= 1000;
+  }
+  transmitByte('0' + digit);
+
+                            /* decimal point here b/c dividing by 1000 */
+  transmitByte('.');
+
+                                                    /* add up hundreds */
+  digit = 0;
+  while (value >= 100) {
+    digit++;
+    value -= 100;
+  }
+  transmitByte('0' + digit);
+                                                        /* add up tens */
+  digit = 0;
+  while (value >= 10) {
+    digit++;
+    value -= 10;
+  }
+  transmitByte('0' + digit);
+
+  // Ones digit is easy.
+  transmitByte('0' + value);
+
+  printString(" seconds.\r\n");
+}
+
+void printComments(uint16_t value) {
+            /* Given a value in milliseconds, rates your reaction time */
+  if (value > 2000) {
+    printString("---->  Ummm...this is a reaction timer...\r\n");
+  }
+  else if (value > 1000) {
+    printString("---->  Hello?\r\n");
+  }
+  else if (value > 500) {
+    printString("---->  Slow.\r\n");
+  }
+  else if (value > 250) {
+    printString("---->  Have another cup of coffee.\r\n");
+  }
+  else if (value > 200) {
+    printString("---->  Respectable.\r\n");
+  }
+  else if (value >= 150) {
+    printString("---->  Fast.\r\n");
+  }
+  else if (value < 150) {
+    printString("---->  Amazing!\r\n");
+  }
+}
+
+void randomDelay(void) {
+                        /* Waits for a "random" delay from 1 - 3.5 sec */
+                           /* Requires timer 1 initialized and running */
+  /* It's not really random, but very hard to control --
+     like coin-flipping. */
+  uint8_t randomTime;
+
+  _delay_ms(1000);                              /* wait at least 1 sec */
+  randomTime = (uint8_t) TCNT1;
+  /* type-casting the 16-bit TCNT1 as an 8-bit number keeps
+     only the 8 least-significant (fastest-changing) bits  */
+  while (--randomTime) {
+    _delay_ms(10);                      /* max value is 255 ~= 2.5 sec */
+  }
+}