--- /dev/null
+// $Id$
+
+/* tab:2
+ *
+ *
+ * "Copyright (c) 2000-2004 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation for any purpose, without fee, and without written agreement is
+ * hereby granted, provided that the above copyright notice, the following
+ * two paragraphs and the author appear in all copies of this software.
+ *
+ * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
+ * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
+ * CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS."
+ *
+ */
+
+/**
+ * @author Jonathan Hui <jwhui@cs.berkeley.edu>
+ */
+
+module VoltageC {
+ provides {
+ interface Voltage;
+ }
+}
+
+implementation {
+
+ enum {
+ VTHRESH = 0xE66, // 2.7V
+ };
+
+ command bool Voltage.okToProgram() {
+
+ int i;
+
+ // Turn on and set up ADC12 with REF_1_5V
+ ADC12CTL0 = ADC12ON | SHT0_2 | REFON;
+ // Use sampling timer
+ ADC12CTL1 = SHP;
+ // Set up to sample voltage
+ ADC12MCTL0 = EOS | SREF_1 | INCH_11;
+ // Delay for reference start-up
+ for ( i=0; i<0x3600; i++ );
+
+ // Enable conversions
+ ADC12CTL0 |= ENC;
+ // Start conversion
+ ADC12CTL0 |= ADC12SC;
+ // Wait for completion
+ while ((ADC12IFG & BIT0) == 0);
+
+ // Turn off ADC12
+ ADC12CTL0 &= ~ENC;
+ ADC12CTL0 = 0;
+
+ // Check if voltage is greater than 2.7V
+ return ( ADC12MEM0 > VTHRESH );
+
+ }
+
+}