--- a/main.c	Tue Jul 03 21:55:50 2012 +0800
+++ b/main.c	Tue Jul 03 22:44:21 2012 +0800
@@ -28,8 +28,8 @@
 // limited to uint16_t
 #define MEASURE_WAKE 60
 
-#define VALUE_NOSENSOR -9000
-#define VALUE_BROKEN -8000
+#define VALUE_NOSENSOR 0x07D0 // 125 degrees
+#define VALUE_BROKEN 0x07D1 // 125.0625
 
 // limited to uint16_t
 #define COMMS_WAKE 3600 // XXX testing
@@ -81,8 +81,8 @@
 
 static uint16_t n_measurements;
 
-// stored as decidegrees
-static int16_t measurements[NUM_MEASUREMENTS][MAX_SENSORS];
+// stored as 
+static uint16_t measurements[NUM_MEASUREMENTS][MAX_SENSORS];
 static uint32_t first_measurement_clock;
 // last_measurement_clock is redundant but checks that we're not missing
 // samples
@@ -300,7 +300,7 @@
         fprintf_P(crc_stdout, PSTR("meas%hu="), n);
         for (uint8_t s = 0; s < n_sensors; s++)
         {
-            fprintf_P(crc_stdout, PSTR(" %hu"), measurements[n][s]);
+            fprintf_P(crc_stdout, PSTR(" %04hx"), measurements[n][s]);
         }
         fputc('\n', crc_stdout);
     }
@@ -662,6 +662,8 @@
     uint8_t n_sensors;
     eeprom_read(n_sensors, n_sensors);
 
+    blink();
+
     simple_ds18b20_start_meas(NULL);
     // sleep rather than using a long delay
     deep_sleep();
@@ -674,23 +676,23 @@
 
     for (uint8_t s = 0; s < MAX_SENSORS; s++)
     {
-        int16_t decicelsius;
+        uint16_t reading;
         if (s >= n_sensors)
         {
-            decicelsius = VALUE_NOSENSOR;
+            reading = VALUE_NOSENSOR;
         }
         else
         {
             uint8_t id[ID_LEN];
             eeprom_read_to(id, sensor_id[s], ID_LEN);
 
-            uint8_t ret = simple_ds18b20_read_decicelsius(id, &decicelsius);
+            uint8_t ret = simple_ds18b20_read_raw(id, &reading);
             if (ret != DS18X20_OK)
             {
-                decicelsius = VALUE_BROKEN;
+                reading = VALUE_BROKEN;
             }
         }
-        measurements[n_measurements][s] = decicelsius;
+        measurements[n_measurements][s] = reading;
     }
 
     ATOMIC_BLOCK(ATOMIC_RESTORESTATE)
@@ -816,10 +818,6 @@
         }
 
         deep_sleep();
-        if (clock_epoch % 60 == 0)
-        {
-            blink();
-        }
     }
 
     return 0;   /* never reached */

--- a/simple_ds18b20.c	Tue Jul 03 21:55:50 2012 +0800
+++ b/simple_ds18b20.c	Tue Jul 03 22:44:21 2012 +0800
@@ -125,6 +125,23 @@
 	return ret;
 }
 
+uint8_t 
+simple_ds18b20_read_raw( uint8_t id[], uint16_t *reading )
+{
+	uint8_t sp[DS18X20_SP_SIZE];
+	uint8_t ret;
+	
+	if (id)
+	{
+		ow_reset();
+	}
+	ret = read_scratchpad( id, sp, DS18X20_SP_SIZE );
+	if ( ret == DS18X20_OK ) {
+        *reading = sp[0] | (sp[1] << 8);
+	}
+	return ret;
+}
+
 static void 
 printhex_nibble(const unsigned char b, FILE *stream)
 {

--- a/simple_ds18b20.h	Tue Jul 03 21:55:50 2012 +0800
+++ b/simple_ds18b20.h	Tue Jul 03 22:44:21 2012 +0800
@@ -9,6 +9,7 @@
 void printhex(uint8_t *id, uint8_t n, FILE *stream);
 void printhex_byte( const unsigned char  b, FILE *stream );
 uint8_t simple_ds18b20_read_decicelsius( uint8_t id[], int16_t *decicelsius );
+uint8_t simple_ds18b20_read_raw( uint8_t id[], uint16_t *reading );
 uint8_t simple_ds18b20_read_all();
 
 #endif // SIMPLE_DS18B20_H_

--- a/web/log.py	Tue Jul 03 21:55:50 2012 +0800
+++ b/web/log.py	Tue Jul 03 22:44:21 2012 +0800
@@ -11,6 +11,7 @@
 import sqlite3
 import traceback
 import datetime
+import struct
 from colorsys import hls_to_rgb
 
 import config
@@ -143,6 +144,10 @@
     f.flush()
     return f
 
+def convert_ds18b20_12bit(reading):
+    value = struct.unpack('>h', binascii.unhexlify(reading))[0]
+    return value * 0.0625
+
 def parse(lines):
    
     debugf = record_debug(lines)
@@ -160,10 +165,6 @@
     for s in sensors:
         meas.append([])
 
-    def val_scale(v):
-        # convert decidegrees to degrees
-        return 0.1 * v
-
     for n in xrange(num_measurements):
         vals = [val_scale(int(x)) for x in entries["meas%d" % n].strip().split()]
         if len(vals) != num_sensors:

--- a/web/test.py	Tue Jul 03 21:55:50 2012 +0800
+++ b/web/test.py	Tue Jul 03 22:44:21 2012 +0800
@@ -1,5 +1,12 @@
 #!/usr/bin/env python
-import log
 import time
+import struct
+import sys
+import binascii
 
-log.sensor_update("test1", [22,22,22.1,22.4,22.5], time.time() - 10, 300)
+def convert_ds18b20_12bit(reading):
+    value = struct.unpack('>h', binascii.unhexlify(reading))[0]
+    return value * 0.0625
+
+if __name__ == '__main__':
+    print convert_ds18b20_12bit(sys.argv[1])