diff --git a/avr/modules/0BUILD b/avr/modules/0BUILD
index afc8cda..ec3eaaf 100644
--- a/avr/modules/0BUILD
+++ b/avr/modules/0BUILD
@@ -6,6 +6,7 @@
     basetimer
     bmp280
     ccs811
+    clock
     cny70
     com2
     comproto
diff --git a/avr/modules/clock/0BUILD b/avr/modules/clock/0BUILD
new file mode 100644
index 0000000..febd367
--- /dev/null
+++ b/avr/modules/clock/0BUILD
@@ -0,0 +1,11 @@
+<?xml?>
+
+<gwbuild>
+
+  <extradist>
+    main.asm
+  </extradist>
+
+</gwbuild>
+
+
diff --git a/avr/modules/clock/main.asm b/avr/modules/clock/main.asm
new file mode 100644
index 0000000..f3bf26f
--- /dev/null
+++ b/avr/modules/clock/main.asm
@@ -0,0 +1,132 @@
+; ***************************************************************************
+; copyright   : (C) 2025 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.   *
+; ***************************************************************************
+
+
+; Counts seconds, minutes and hours
+;
+; calls onEverySecond, onEveryMinute, onEveryHour and onEveryDay
+;
+
+
+
+; ***************************************************************************
+; defs
+
+
+
+
+
+; ***************************************************************************
+; data
+
+.dseg
+
+clockModuleData:
+clockModuleTickCounter:      .byte 1
+clockModuleCounterSecs:      .byte 1
+clockModuleCounterMins:      .byte 1
+clockModuleCounterHours:     .byte 1
+clockModuleData_end:
+
+
+
+
+; ***************************************************************************
+; code
+
+.cseg
+
+CLOCK_BEGIN:
+
+
+
+; ---------------------------------------------------------------------------
+; @routine Clock_Init
+;
+; @clobbers r16, r17, x
+
+Clock_Init:
+  ; reset data in SDRAM
+  ldi xh, HIGH(clockModuleData)
+  ldi xl, LOW(clockModuleData)
+  clr r16
+  ldi r17, (clockModuleData_end-clockModuleData)
+  rcall Utils_FillSram                ; (R17, X)
+  sec
+  ret
+; @end
+
+
+
+; ---------------------------------------------------------------------------
+; @routine Clock_Fini
+;
+
+Clock_Fini:
+  ret
+; @end
+
+
+
+; ---------------------------------------------------------------------------
+; @routine Clock_Every100ms
+;
+
+Clock_Every100ms:
+  lds r16, clockModuleTickCounter
+  inc r16
+  cpi r16, 10
+  brcc Clock_Every100ms_inc1s
+  sts clockModuleTickCounter, r16
+  ret
+Clock_Every100ms_inc1s:
+  clr r16
+  sts clockModuleTickCounter, r16
+  rcall onEverySecond
+  lds r16, clockModuleCounterSecs
+  inc r16
+  cpi r16, 60
+  brcc Clock_Every100ms_inc1m
+  sts clockModuleCounterSecs, r16
+  ret
+Clock_Every100ms_inc1m:
+  clr r16
+  sts clockModuleCounterSecs, r16
+  rcall onEveryMinute
+  lds r16, clockModuleCounterMins
+  inc r16
+  cpi r16, 60
+  brcc Clock_Every100ms_inc1h
+  sts clockModuleCounterMins, r16
+  ret
+Clock_Every100ms_inc1h:
+  clr r16
+  sts clockModuleCounterMins, r16
+  rcall onEveryHour
+  lds r16, clockModuleCounterHours
+  inc r16
+  cpi r16, 24
+  brcc Clock_Every100ms_1d
+  sts clockModuleCounterHours, r16
+  ret
+Clock_Every100ms_1d:
+  clr r16
+  sts clockModuleCounterHours, r16
+  rcall onEveryDay
+  ret
+; @end
+
+
+
+
+
+CLOCK_END:
+.equ MODULE_SIZE_CLOCK = CLOCK_END-CLOCK_BEGIN
+
+