diff --git a/avr/apps/router/main.asm b/avr/apps/router/main.asm
index 76e1d0d..047a126 100644
--- a/avr/apps/router/main.asm
+++ b/avr/apps/router/main.asm
@@ -64,6 +64,10 @@ AppRouter_Init:
   ; set interface number for NETDEV1
   ldi r16, NETDEV1_IFACENUM
   sts netInterfaceData2+NET_IFACE_OFFS_IFACENUM, r16
+  
+  ldi r18, NETMSG_CMD_ADDRESS_RANGE
+  rcall appRouterSendRangeMsgToDev1
+  
   ret
 ; @end
 
@@ -128,6 +132,7 @@ appRouterHandleMsgAnyDev_handleRebootMsg:
   ret
 appRouterHandleMsgAnyDev_handlePingMsg:
   rcall appRouterHandlePingRequest
+  clc
   ret
 appRouterHandleMsgAnyDev_handleSetValue:
   rcall NETMSG_ValueRead                            ; (none)
@@ -174,7 +179,7 @@ appRouterHandleDev1Msg:
   pop xl
   rjmp appRouterHandleDev1Msg_end
 appRouterHandleDev1Msg_savedX:
-  adiw xh:xl, NETMSG_OFFS_CMD                 ; maybe move ping/reboot handling to all/main.asm?
+  adiw xh:xl, NETMSG_OFFS_CMD
   ld r16, X
   sbiw xh:xl, NETMSG_OFFS_CMD
   cpi r16, NETMSG_CMD_NEED_ADDRESS
@@ -182,6 +187,7 @@ appRouterHandleDev1Msg_savedX:
   cpi r16, NETMSG_CMD_CLAIM_ADDRESS
   breq appRouterHandleDev1Msg_handleClaimAddr
   ; add more here
+  ldi r16, 0
   rjmp appRouterHandleDev1Msg_clcRet
 appRouterHandleDev1Msg_handleNeedAddr:
   ldi r18, NETMSG_CMD_ADDRESS_RANGE
@@ -255,7 +261,7 @@ appRouterSendAddrMsgToDev1:
     bigcall NETMSG_Address_Write          ; (R16, R17, R18, R19, R20, R21)
     sbiw xh:xl, 1
   pop r16
-  rcall appRouterSendMsgToDev1            ; (R16, R17, R18, X, Y)
+  rcall appRouterSendMsgToDev1            ; (R16, R17, R18, R24, R25, X, Y)
 appRouterSendAddrMsgToDev1_end:
   ret
 ; @end
@@ -266,7 +272,8 @@ appRouterSendAddrMsgToDev1_end:
 ; @routine appRouterSendRangeMsgToDev1
 ;
 ; @param R18 msg code
-; @clobbers (R16, R17, R18, R19, R20, R21, X, Y)
+; @return CFLAG set if message enqueued, cleared on error
+; @clobbers (R16, R17, R18, R19, R20, R21, R24, R25, X, Y)
 
 appRouterSendRangeMsgToDev1:
   bigcall NET_Buffer_Alloc                ; (R16, R17, X)
@@ -278,7 +285,7 @@ appRouterSendRangeMsgToDev1:
     bigcall NETMSG_Range_Write            ; (R16, R17, R18, R19, R20, R21)
     sbiw xh:xl, 1
   pop r16
-  rcall appRouterSendMsgToDev1            ; (R16, R17, R18, X, Y)
+  rcall appRouterSendMsgToDev1            ; (R16, R17, R18, R24, R25, X, Y)
 appRouterSendRangeMsgToDev1_end:
   ret
 ; @end
@@ -290,7 +297,8 @@ appRouterSendRangeMsgToDev1_end:
 ;
 ; @param R16 num of allocated buffer
 ; @param X msg to send (points to start of allocated buffer, e.g. buffer header)
-; @clobbers Y (R16, R17, R18, X)
+; @return CFLAG set if message enqueued, cleared on error
+; @clobbers Y (R16, R17, R18, R24, R25, X)
 
 appRouterSendMsgToDev1:
   ldi yl, LOW(netInterfaceData2)
@@ -298,6 +306,8 @@ appRouterSendMsgToDev1:
   bigcall NET_Interface_AddOutgoingMsgNum ; (R17, R18, X)
   brcs appRouterSendMsgToDev1_end
   bigcall NET_Buffer_ReleaseByNum         ; (R16, X)
+  ldi r16, NET_IFACE_OFFS_ERR_NOBUF_LOW
+  rcall NET_Interface_IncCounter16        ; (R24, R25)
   clc
 appRouterSendMsgToDev1_end:
   ret
@@ -354,27 +364,29 @@ appRouterHandlePingRequest_end:
 ; @routine appRouterCheckRecvdMsg
 ;
 ; Read messages from either interface and forward to the other one.
+;
+; @return CFLAG set if something done, cleared otherwise
 
 appRouterCheckRecvdMsg:
-    rcall NET_PeekNextIncomingMsgNum          ; check read queue (bufNum->r16)
-    brcc appRouterCheckRecvdMsg_end           ; no msg, jmp
-    rcall NET_Buffer_Locate                   ; (R17)
-    rcall appRouterHandleRouterMsgWithHdr     ; filter out router msgs
-    brcs appRouterCheckRecvdMsg_removeMsg     ; handled by router code, don't forward
-    ; let system handle incoming messages
-    adiw xh:xl, 1
-    rcall appRouterLetSysHandleMsg
-    sbiw xh:xl, 1
+  rcall NET_PeekNextIncomingMsgNum          ; check read queue (bufNum->r16)
+  brcc appRouterCheckRecvdMsg_end           ; no msg, jmp
+  rcall NET_Buffer_Locate                   ; (R17)
+  rcall appRouterHandleRouterMsgWithHdr     ; filter out router msgs
+  brcs appRouterCheckRecvdMsg_removeMsg     ; handled by router code, don't forward
+  ; let system handle incoming messages
+  adiw xh:xl, 1
+  rcall appRouterLetSysHandleMsg
+  sbiw xh:xl, 1
 
-    ; forward to other interface
-    ld r17, X
-    andi r17, (1<<NET_IFACE_BUFFER_IFACENUM1_BIT) | (1<<NET_IFACE_BUFFER_IFACENUM0_BIT)
-    rcall appRouterReverseInterfaceNum                 ; (R16, R17)
-    rcall appRouterAddMsgToInterface
-    brcc appRouterCheckRecvdMsg_end                    ; could not add, jmp
-    rcall NET_GetNextIncomingMsgNum                    ; take off the queue
-  rjmp appRouterCheckRecvdMsg
-  
+  ; forward to other interface
+  ld r17, X
+  andi r17, (1<<NET_IFACE_BUFFER_IFACENUM1_BIT) | (1<<NET_IFACE_BUFFER_IFACENUM0_BIT)
+  rcall appRouterReverseInterfaceNum                 ; (R16, R17)
+  rcall appRouterAddMsgToInterface
+  brcc appRouterCheckRecvdMsg_end                    ; could not add, jmp
+  rcall NET_GetNextIncomingMsgNum                    ; take off the queue
+  sec
+  ret
 appRouterCheckRecvdMsg_removeMsg:
   rcall NET_GetNextIncomingMsgNum                    ; take off the queue
   rcall NET_Buffer_ReleaseByNum                      ; (R16, X)
@@ -392,8 +404,8 @@ appRouterCheckRecvdMsg_end:
 
 appRouterHandleRouterMsgWithHdr:
   ld r17, X
-  andi r17, (1<<NET_IFACE_BUFFER_IFACENUM1_BIT) | (1<<NET_IFACE_BUFFER_IFACENUM0_BIT)
   adiw xh:xl, 1
+  andi r17, (1<<NET_IFACE_BUFFER_IFACENUM1_BIT) | (1<<NET_IFACE_BUFFER_IFACENUM0_BIT)
   cpi r17, NETDEV1_IFACENUM
   brne appRouterHandleRouterMsgWithHdr_any
   rcall appRouterHandleDev1Msg                       ; handle messages from controlled subnet
diff --git a/avr/devices/all/apps.asm b/avr/devices/all/apps.asm
index 0c17385..92c89b1 100644
--- a/avr/devices/all/apps.asm
+++ b/avr/devices/all/apps.asm
@@ -66,11 +66,21 @@ initApps:
 ;
 
 runApps:
+  clr r16
 #ifdef APPS_ROUTER
-  bigcall AppRouter_Run
+  push r16
+    bigcall AppRouter_Run
+  pop r16
+  sbci r16, 0              ; decrease r16 only if CFLAG set
 #endif
 
   ; add more modules here
+
+  tst r16
+  clc
+  breq runApps_end
+  sec
+runApps_end:
   ret
 ; @end
 
diff --git a/avr/devices/all/includes.asm b/avr/devices/all/includes.asm
index 8ee7ca3..220c03e 100644
--- a/avr/devices/all/includes.asm
+++ b/avr/devices/all/includes.asm
@@ -241,6 +241,8 @@
 .include "modules/network/msg/pong-w.asm"
 .include "modules/network/msg/range-d.asm"
 .include "modules/network/msg/range-r.asm"
+.include "common/eeprom-r.asm"
+.include "common/eeprom-w.asm"
 #endif
 
 
diff --git a/avr/devices/all/main.asm b/avr/devices/all/main.asm
index d752723..a2c94e1 100644
--- a/avr/devices/all/main.asm
+++ b/avr/devices/all/main.asm
@@ -55,10 +55,26 @@ main:
 
 main_loop:
     bigcall systemSleep   ; system-dependant
-    bigcall runModules
-    bigcall runApps
+
+    ; run loop as long as some run function returns with CFLAG set
+main_runLoop:
+      clr r16
+      push r16
+        bigcall runModules
+      pop r16
+      sbci r16, 0
+      
+      push r16
+        bigcall runApps
+      pop r16
+      sbci r16, 0
     
-    bigcall onEveryLoop   ; call into main app
+      push r16
+        bigcall onEveryLoop   ; call into main app
+      pop r16
+
+      tst r16
+    brne main_runLoop
     
 #ifdef MODULES_NETWORK
   #ifndef MAIN_WITHOUT_MSG_HANDLING
diff --git a/avr/devices/all/modules.asm b/avr/devices/all/modules.asm
index ab73847..5cdbcb0 100644
--- a/avr/devices/all/modules.asm
+++ b/avr/devices/all/modules.asm
@@ -175,56 +175,46 @@ initModules:
 ; USED: depending on called routines
 
 runModules:
-  bigcall BaseTimer_Run
+  clr r16
+  
+  push r16
+    bigcall BaseTimer_Run
+  pop r16
   
-#ifdef MODULES_COM
-; COM module (call until carry flag cleared but at most 10 times to not starve other modules)
-  ldi r16, 10
-runModules_Com:
-    push r16
-      bigcall Com2_Run
-    pop r16
-    brcc runModules_ComEnd
-    dec r16
-  brne runModules_Com
-runModules_ComEnd:  
-#endif
-
 #ifdef MODULES_TTYONUART1
-  bigcall TtyOnUart1_Run
+  push r16
+    bigcall TtyOnUart1_Run
+  pop r16
 #endif
 
 #ifdef MODULES_COMONUART0
-  bigcall ComOnUart0_Run
+  push r16
+    bigcall ComOnUart0_Run
+  pop r16
+  sbci r16, 0
 #endif
 
 #ifdef MODULES_COMONUART1
-  bigcall ComOnUart1_Run
+  push r16
+    bigcall ComOnUart1_Run
+  pop r16
+  sbci r16, 0
 #endif
 
 #ifdef MODULES_STATS
-  bigcall Stats_Run
+  push r16
+    bigcall Stats_Run
+  pop r16
 #endif
 
-#ifdef MODULES_REED
-  bigcall REED_Run
-#endif
-
-#ifdef MODULES_CNY70
-  bigcall CNY70_Run
-#endif
-
-#ifdef MODULES_MOTION_LIGHT
-;  rcall MotionLight_Run
-#endif
-
-
-#ifdef MODULES_TCRT1000
-;  rcall TCRT1K_Run
-#endif
-
-
   ; add more modules here
+
+  ; check for repeat request
+  tst r16
+  clc
+  breq runModules_end
+  sec
+runModules_end:
   ret
 
 
diff --git a/avr/modules/uart_hw2/comonuart0.asm b/avr/modules/uart_hw2/comonuart0.asm
index 3534567..60f718a 100644
--- a/avr/modules/uart_hw2/comonuart0.asm
+++ b/avr/modules/uart_hw2/comonuart0.asm
@@ -147,20 +147,32 @@ comOnUart0StartReading:
 ; ---------------------------------------------------------------------------
 ; @routine ComOnUart0_Run @global
 ;
+; @return CFLAG set if something done, cleared otherwise
 ; @clobbers all
 
 ComOnUart0_Run:
   ldi yl, LOW(comOnUart0_iface)
   ldi yh, HIGH(comOnUart0_iface)
   ldd r16, Y+UART_HW2_IFACE_OFFS_MODE
+  clr r18
 ComOnUart0_Run_loop:
-    push r16                   ; current state
-      rcall comOnUart0RunMode  ; (all but Y)
-    pop r17                    ; previous state (pop from r16 into r17)
+    push r18
+      push r16                   ; current state
+        rcall comOnUart0RunMode  ; (all but Y)
+      pop r17                    ; previous state (pop from r16 into r17)
+    pop r18
     ; read new state
     ldd r16, Y+UART_HW2_IFACE_OFFS_MODE
     cp r16, r17
-  brne ComOnUart0_Run_loop  ; state changed, run again
+    breq ComOnUart0_Run_loopEnd
+    ldi r18, 1
+  rjmp ComOnUart0_Run_loop  ; state changed, run again
+ComOnUart0_Run_loopEnd:
+  tst r18
+  clc
+  breq ComOnUart0_Run_end
+  sec
+ComOnUart0_Run_end:
   ret
 ; @end
 
diff --git a/avr/modules/uart_hw2/comonuart1.asm b/avr/modules/uart_hw2/comonuart1.asm
index 27c51ec..6f87faf 100644
--- a/avr/modules/uart_hw2/comonuart1.asm
+++ b/avr/modules/uart_hw2/comonuart1.asm
@@ -147,20 +147,32 @@ comOnUart1StartReading:
 ; ---------------------------------------------------------------------------
 ; @routine ComOnUart1_Run @global
 ;
+; @return CFLAG set if something done, cleared otherwise
 ; @clobbers all
 
 ComOnUart1_Run:
   ldi yl, LOW(comOnUart1_iface)
   ldi yh, HIGH(comOnUart1_iface)
   ldd r16, Y+UART_HW2_IFACE_OFFS_MODE
+  clr r18
 ComOnUart1_Run_loop:
-    push r16                   ; current state
-      rcall comOnUart1RunMode  ; (all but Y)
-    pop r17                    ; previous state (pop from r16 into r17)
+    push r18
+      push r16                   ; current state
+        rcall comOnUart1RunMode  ; (all but Y)
+      pop r17                    ; previous state (pop from r16 into r17)
+    pop r18
     ; read new state
     ldd r16, Y+UART_HW2_IFACE_OFFS_MODE
     cp r16, r17
-  brne ComOnUart1_Run_loop  ; state changed, run again
+    breq ComOnUart1_Run_loopEnd
+    ldi r18, 1
+  rjmp ComOnUart1_Run_loop  ; state changed, run again
+ComOnUart1_Run_loopEnd:
+  tst r18
+  clc
+  breq ComOnUart1_Run_end
+  sec
+ComOnUart1_Run_end:
   ret
 ; @end