diff --git a/avr/modules/0BUILD b/avr/modules/0BUILD
index 8c898bc..2ff0e01 100644
--- a/avr/modules/0BUILD
+++ b/avr/modules/0BUILD
@@ -23,6 +23,7 @@
     ma_light
     motion
     uart_bitbang
+    tcrt1000
   </subdirs>
 
 </gwbuild>
diff --git a/avr/modules/tcrt1000/0BUILD b/avr/modules/tcrt1000/0BUILD
new file mode 100644
index 0000000..febd367
--- /dev/null
+++ b/avr/modules/tcrt1000/0BUILD
@@ -0,0 +1,11 @@
+<?xml?>
+
+<gwbuild>
+
+  <extradist>
+    main.asm
+  </extradist>
+
+</gwbuild>
+
+
diff --git a/avr/modules/tcrt1000/main.asm b/avr/modules/tcrt1000/main.asm
new file mode 100644
index 0000000..7732912
--- /dev/null
+++ b/avr/modules/tcrt1000/main.asm
@@ -0,0 +1,189 @@
+; ***************************************************************************
+; copyright   : (C) 2023 by Martin Preuss
+; email       : martin@libchipcard.de
+;
+; ***************************************************************************
+; * This file is part of the project "AqHome".                              *
+; * Please see toplevel file COPYING of that project for license details.   *
+; ***************************************************************************
+
+
+
+.equ TCRT1K_INTERVAL          = 7
+.equ TCRT1K_LIMIT             = 170
+
+.equ TCRT1K_STATE_OPEN        = 255
+.equ TCRT1K_STATE_CLOSED      = 0
+
+.equ TCRT1K_FLAGS_REPORT_CHANGE_BIT = 0
+
+
+; ***************************************************************************
+; data
+
+.dseg
+
+tcrt1kDataBegin:
+  tcrt1kTimer:        .byte 1
+  tcrt1kLastState:    .byte 1
+  tcrt1kLastValue:    .byte 1
+  tcrt1kStateCounter: .byte 1
+  tcrt1kFlags:        .byte 1
+tcrt1kDataEnd:
+
+
+
+
+; ***************************************************************************
+; code
+
+.cseg
+
+
+
+; ---------------------------------------------------------------------------
+; @routine TCRT1K_Init
+;
+; Init module.
+;
+; @return CFLAG always set
+
+TCRT1K_Init:
+  ; preset SRAM data area
+  ldi xh, HIGH(tcrt1kDataBegin)
+  ldi xl, LOW(tcrt1kDataBegin)
+  clr r16
+  ldi r17, (tcrt1kDataEnd-tcrt1kDataBegin)
+  rcall Utils_FillSram
+
+  ; setup pins
+  sbi TCRT1K_LED_DDR, TCRT1K_LED_PIN                 ; set DATA port as output
+  cbi TCRT1K_LED_PORT, TCRT1K_LED_PIN                ; LED off
+  cbi TCRT1K_ADC_PORT, TCRT1K_ADC_PIN                ; disable internal pullup for ADC
+  cbi TCRT1K_ADC_DDR, TCRT1K_ADC_PIN                 ; set ADC port as input
+
+  ldi r16, TCRT1K_ADC_MUX                            ; select input pin, use Vcc as reference voltage
+  out ADMUX, r16
+  ldi r16, (1 << ADLAR)
+  out ADCSRB, r16
+  ldi r16, (1 << ADEN) | (1 << ADPS1) | (1 << ADPS0) ; enable, prescaler 8
+  out ADCSRA, r16
+  
+  ldi r16, TCRT1K_INTERVAL
+  sts tcrt1kTimer, r16
+  
+  sec
+  ret
+
+
+
+TCRT1K_Fini:
+  sec
+  ret
+
+
+
+TCRT1K_Every100ms:
+  lds r16, tcrt1kTimer
+  dec r16
+  breq TCRT1K_Every100ms_readValue
+  sts tcrt1kTimer, r16
+  cpi r16, 2
+  breq TCRT1K_Every100ms_ledOn
+  cpi r16, 1
+  breq TCRT1K_Every100ms_startMeasure
+  ret
+TCRT1K_Every100ms_ledOn:
+  sbi TCRT1K_LED_PORT, TCRT1K_LED_PIN ; LED on
+  ret
+TCRT1K_Every100ms_startMeasure:
+  sbi ADCSRA, ADSC                    ; start conversion
+  ret
+TCRT1K_Every100ms_readValue:
+  sbic ADCSRA, ADSC
+    ret ; return if bit still set, leave tcrt1kTimer at "1"
+  ; conversion complete, read value
+  ldi r16, TCRT1K_INTERVAL            ; restart timer
+  sts tcrt1kTimer, r16
+  in r16, ADCH                        ; read value from ADC
+  cbi TCRT1K_LED_PORT, TCRT1K_LED_PIN ; LED off
+  sts tcrt1kLastValue, r16
+
+  cpi r16, TCRT1K_LIMIT
+  ldi r16, TCRT1K_STATE_CLOSED
+  brcs TCRT1K_Every100ms_checkChange
+  ldi r16, TCRT1K_STATE_OPEN
+TCRT1K_Every100ms_checkChange:
+  lds r17, tcrt1kLastState
+  cp r16, r17
+  brne TCRT1K_Every100ms_stateChanged
+  lds r16, tcrt1kStateCounter
+  inc r16
+  brne TCRT1K_Every100ms_incStateCounter
+  ret
+TCRT1K_Every100ms_incStateCounter:
+  sts tcrt1kStateCounter, r16
+  cpi r16, 1                            ; report change after one interval
+  breq TCRT1K_Every100ms_reportChange   
+  cpi r16, 2                            ; report change after two intervals
+  breq TCRT1K_Every100ms_reportChange
+  cpi r16, 10                           ; report change after two intervals
+  breq TCRT1K_Every100ms_reportChange
+  ret
+TCRT1K_Every100ms_reportChange:
+  lds r16, tcrt1kFlags
+  ori r16, (1<<TCRT1K_FLAGS_REPORT_CHANGE_BIT)
+  sts tcrt1kFlags, r16
+  ret
+TCRT1K_Every100ms_stateChanged:
+  sts tcrt1kLastState, r16              ; store new state
+  clr r16
+  sts tcrt1kStateCounter, r16
+TCRT1K_Every100ms_end:
+  ret
+; @end
+
+
+
+TCRT1K_Run:
+  lds r16, tcrt1kFlags
+  andi r16, (1<<TCRT1K_FLAGS_REPORT_CHANGE_BIT)
+  breq TCRT1K_Run_retnc
+  rcall TCRT1K_SendState
+  brcc TCRT1K_Run_retnc
+  lds r16, tcrt1kFlags
+  andi r16, ~(1<<TCRT1K_FLAGS_REPORT_CHANGE_BIT)
+  sts tcrt1kFlags, r16
+  sec
+  ret
+TCRT1K_Run_retnc:
+  clc
+  ret
+
+
+
+
+
+TCRT1K_SendState:
+  lds r16, com2Address
+  tst r16
+  brne TCRT1K_SendState_haveAddress
+  clc
+  ret
+TCRT1K_SendState_haveAddress:
+  ldi r16, 0xff                      ; destination address
+  ldi r17, VALUE_ID_TCRT1K           ; value id
+  ldi r22, AQHOME_VALUETYPE_DOOR
+  lds r18, tcrt1kLastState           ; value
+  clr r19
+  ldi r20, 1                         ; denominator
+;  lds r20, tcrt1kLastValue
+  clr r21
+  ldi xl, LOW(com2SendBuffer)
+  ldi xh, HIGH(com2SendBuffer)
+  rcall CPRO_WriteReportValue
+  rjmp COM2_SendPacket
+
+
+
+