diff --git a/avr/devices/n21/defs.asm b/avr/devices/n21/defs.asm
index d4952ca..2b5eb92 100644
--- a/avr/devices/n21/defs.asm
+++ b/avr/devices/n21/defs.asm
@@ -13,9 +13,9 @@
 ;                                 AtTiny84
 ;                                 --------
 ;                            VCC  1     14  GND
-;                            PB0  2     13  PA0  AUX-A0
+;                            PB0  2     13  PA0  TCRT1000_Enable
 ;                  PIR       PB1  3     12  PA1  COM-DATA
-;                  /RESET    PB3  4     11  PA2
+;                  /RESET    PB3  4     11  PA2  TCRT1000_Input
 ;                  AUX-B2    PB2  5     10  PA3  LED
 ;                  COM_ATTN  PA7  6      9  PA4  TWI-SCL
 ;                  TWI-SDA   PA6  7      8  PA5
@@ -125,3 +125,19 @@
 
 
 
+; ---------------------------------------------------------------------------
+; ADC/TCRT1K
+
+
+.equ TCRT1K_LED_PORT    = PORTA
+.equ TCRT1K_LED_DDR     = DDRA
+.equ TCRT1K_LED_PIN     = PORTA0
+
+.equ TCRT1K_ADC_PORT    = PORTA ; adc2
+.equ TCRT1K_ADC_DDR     = DDRA
+.equ TCRT1K_ADC_PIN     = PORTA2
+.equ TCRT1K_ADC_MUX     = MUX2
+.equ TCRT1K_ADC_ADCSRB  = ADC2D
+
+
+
diff --git a/avr/devices/n21/main.asm b/avr/devices/n21/main.asm
index 79917a1..8e2e52b 100644
--- a/avr/devices/n21/main.asm
+++ b/avr/devices/n21/main.asm
@@ -65,6 +65,7 @@
 ;#define MODULES_OWI_MASTER
 ;#define MODULES_DS18B20
 #define MODULES_MOTION
+#define MODULES_TCRT1000
 
 ; ---------------------------------------------------------------------------
 ; defines for values
@@ -77,6 +78,7 @@
 ;.equ VALUE_ID_REED2        = 0x05
 ;.equ VALUE_ID_DS18B20_TEMP = 0x06
 .equ VALUE_ID_MOTION       = 0x07
+.equ VALUE_ID_TCRT1K       = 0x08
 
 ;.equ VALUE_ID_REED_CONF    = 0x81
 
@@ -198,6 +200,10 @@ firmwareStart:   rjmp main
   .include "modules/motion/main.asm"
 #endif
 
+#ifdef MODULES_TCRT1000
+  .include "modules/tcrt1000/main.asm"
+#endif
+
 ; test
 ;#include "modules/uart_irq/defs.asm"
 ;#include "modules/uart_irq/iface.asm"
@@ -415,6 +421,11 @@ onEvery100ms:
 #ifdef MODULES_MOTION
   rcall Motion_Every100ms
 #endif
+
+#ifdef MODULES_TCRT1000
+  rcall TCRT1K_Every100ms
+#endif
+
   ret