diff --git a/avr/devices/n00/n00_defs.asm b/avr/devices/n00/n00_defs.asm
index 153ebf5..4c6b549 100644
--- a/avr/devices/n00/n00_defs.asm
+++ b/avr/devices/n00/n00_defs.asm
@@ -120,4 +120,15 @@
 
 
 
+; ---------------------------------------------------------------------------
+; 1-Wire Master
+;
+
+.equ OWI_DDR     = DDRB
+.equ OWI_PORTOUT = PORTB
+.equ OWI_PORTIN  = PINB
+.equ OWI_PINNUM  = PORTB2
+
+
+
 
diff --git a/avr/devices/n06/n06_defs.asm b/avr/devices/n06/n06_defs.asm
index 153ebf5..4c6b549 100644
--- a/avr/devices/n06/n06_defs.asm
+++ b/avr/devices/n06/n06_defs.asm
@@ -120,4 +120,15 @@
 
 
 
+; ---------------------------------------------------------------------------
+; 1-Wire Master
+;
+
+.equ OWI_DDR     = DDRB
+.equ OWI_PORTOUT = PORTB
+.equ OWI_PORTIN  = PINB
+.equ OWI_PINNUM  = PORTB2
+
+
+
 
diff --git a/avr/devices/n06/n06_main.asm b/avr/devices/n06/n06_main.asm
index 0a2fa81..5a942bf 100644
--- a/avr/devices/n06/n06_main.asm
+++ b/avr/devices/n06/n06_main.asm
@@ -228,7 +228,7 @@ timerList:
   .dw sramTimerWriteStats,         writeStats,                 0,                   100
 #endif
 #ifdef MODULES_SI7021
-  .dw sramTimerSI7021Measure,      SI7021_PeriodicMeasurement, 0,                   300    ; every 30s
+  .dw sramTimerSI7021Measure,      SI7021_OnTimer,             0,                   300    ; every 30s
   .dw sramTimerSI7021SendTemp,     sendTemp,                   TIMER_FLAGS_IF_ADDR, 600    ; every 60s
   .dw sramTimerSI7021SendHumidity, sendHumidity,               TIMER_FLAGS_IF_ADDR, 600    ; every 60s
 #endif
diff --git a/avr/devices/n11/n11_main.asm b/avr/devices/n11/n11_main.asm
index b72432a..384dfc7 100644
--- a/avr/devices/n11/n11_main.asm
+++ b/avr/devices/n11/n11_main.asm
@@ -240,7 +240,7 @@ timerList:
   .dw sramTimerWriteStats,         writeStats,                 0,                   100
 #endif
 #ifdef MODULES_SI7021
-  .dw sramTimerSI7021Measure,      SI7021_PeriodicMeasurement, 0,                   300    ; every 30s
+  .dw sramTimerSI7021Measure,      SI7021_OnTimer,             0,                   300    ; every 30s
   .dw sramTimerSI7021SendTemp,     sendSI7021Temp,             TIMER_FLAGS_IF_ADDR, 600    ; every 60s
   .dw sramTimerSI7021SendHumidity, sendSI7021Humidity,         TIMER_FLAGS_IF_ADDR, 600    ; every 60s
 #endif
diff --git a/avr/devices/n12/n12_defs.asm b/avr/devices/n12/n12_defs.asm
index da8eb4e..0446294 100644
--- a/avr/devices/n12/n12_defs.asm
+++ b/avr/devices/n12/n12_defs.asm
@@ -138,3 +138,14 @@
 
 
 
+; ---------------------------------------------------------------------------
+; 1-Wire Master
+;
+
+.equ OWI_DDR     = DDRB
+.equ OWI_PORTOUT = PORTB
+.equ OWI_PORTIN  = PINB
+.equ OWI_PINNUM  = PORTB2
+
+
+
diff --git a/avr/devices/n12/n12_main.asm b/avr/devices/n12/n12_main.asm
index 0c32e7b..2c33043 100644
--- a/avr/devices/n12/n12_main.asm
+++ b/avr/devices/n12/n12_main.asm
@@ -228,7 +228,7 @@ timerList:
   .dw sramTimerWriteStats,         writeStats,                 0,                   100
 #endif
 #ifdef MODULES_SI7021
-  .dw sramTimerSI7021Measure,      SI7021_PeriodicMeasurement, 0,                   300    ; every 30s
+  .dw sramTimerSI7021Measure,      SI7021_OnTimer,             0,                   300    ; every 30s
   .dw sramTimerSI7021SendTemp,     sendTemp,                   TIMER_FLAGS_IF_ADDR, 600    ; every 60s
   .dw sramTimerSI7021SendHumidity, sendHumidity,               TIMER_FLAGS_IF_ADDR, 600    ; every 60s
 #endif
diff --git a/avr/modules/si7021/main.asm b/avr/modules/si7021/main.asm
index 8a614ae..13b91b3 100644
--- a/avr/modules/si7021/main.asm
+++ b/avr/modules/si7021/main.asm
@@ -91,7 +91,7 @@ SI7021_Fini:
 
 
 ; ---------------------------------------------------------------------------
-; SI7021_PeriodicMeasurement
+; SI7021_OnTimer
 ;
 ; Call this routine periodically to take measurements.
 ; IN:
@@ -100,44 +100,44 @@ SI7021_Fini:
 ; - CFLAG: set if okay, clear on error
 ; USED:
 
-SI7021_PeriodicMeasurement:
+SI7021_OnTimer:
   in r15, SREG
   push r15
     cli
     lds r17, si7021Flags
     mov r16, r17
     andi r16, SI7021_FLAGS_LASTWASTEMP
-    brne si7021PeriodicMeasurement_hum
+    brne SI7021_OnTimer_hum
     ori r17, SI7021_FLAGS_LASTWASTEMP
     sts si7021Flags, r17
     push r17
       rcall si7021MeasureTemp
     pop r17
-    brcc si7021PeriodicMeasurement_error
+    brcc SI7021_OnTimer_error
     ori r17, SI7021_FLAGS_TEMP_VALID
     sts si7021Flags, r17
     rcall si7021CalcTemp                 ; calculate temp*100 from sensor value
     sts si7021LastTemp, r18
     sts si7021LastTemp+1, r19
-    rjmp si7021PeriodicMeasurement_done
-si7021PeriodicMeasurement_hum:
+    rjmp SI7021_OnTimer_done
+SI7021_OnTimer_hum:
     andi r17, ~SI7021_FLAGS_LASTWASTEMP
     sts si7021Flags, r17
     push r17
       rcall si7021MeasureHumidity
     pop r17
-    brcc si7021PeriodicMeasurement_error
+    brcc SI7021_OnTimer_error
     ori r17, SI7021_FLAGS_HUM_VALID
     sts si7021Flags, r17
     rcall si7021CalcHumidity
     sts si7021LastHumidity, r18
     sts si7021LastHumidity+1, r19
-si7021PeriodicMeasurement_done:
+SI7021_OnTimer_done:
   pop r15
   out SREG, r15
   sec
   ret
-si7021PeriodicMeasurement_error:
+SI7021_OnTimer_error:
   pop r15
   out SREG, r15
   clc