USB_Init() no longer calls sei() to enable global interrupts - this must now be done in the user application once all init code has run.

Projects/TemperatureDataLogger/TempDataLogger.c

@@ -137,16 +137,17 @@ ISR(TIMER1_COMPA_vect, ISR_BLOCK)
  */
 int main(void)
 {
+	SetupHardware();
+
 	/* Fetch logging interval from EEPROM */
 	LoggingInterval500MS_SRAM = eeprom_read_byte(&LoggingInterval500MS_EEPROM);
 
-	SetupHardware();
-
-	LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
-
 	/* Mount and open the log file on the dataflash FAT partition */
 	OpenLogFile();
 
+	LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
+	sei();
+
 	/* Discard the first sample from the temperature sensor, as it is generally incorrect */
 	volatile uint8_t Dummy = Temperature_GetTemperature();
 	(void)Dummy;

Projects/TemperatureDataLogger/TempDataLogger.h

@@ -40,6 +40,7 @@
 		#include <avr/io.h>
 		#include <avr/wdt.h>
 		#include <avr/power.h>
+		#include <avr/interrupt.h>
 		#include <stdio.h>
 		
 		#include "Descriptors.h"