diff --git a/avr/devices/r04/defs.asm b/avr/devices/r04/defs.asm
index e89b454..b4de9c0 100644
--- a/avr/devices/r04/defs.asm
+++ b/avr/devices/r04/defs.asm
@@ -74,11 +74,11 @@
 .equ COM_IRQ_GIMSK_ATTN0  = PCIE0
 
 ; compatibility
-.equ COM_ATTN_DDR       = COM_ATTN0_DDR
-.equ COM_ATTN_INPUT     = COM_ATTN0_INPUT
-.equ COM_ATTN_OUTPUT    = COM_ATTN0_OUTPUT
-.equ COM_ATTN_PUE       = COM_ATTN0_PUE
-.equ COM_ATTN_PIN       = COM_ATTN0_PIN
+;.equ COM_ATTN_DDR       = COM_ATTN0_DDR
+;.equ COM_ATTN_INPUT     = COM_ATTN0_INPUT
+;.equ COM_ATTN_OUTPUT    = COM_ATTN0_OUTPUT
+;.equ COM_ATTN_PUE       = COM_ATTN0_PUE
+;.equ COM_ATTN_PIN       = COM_ATTN0_PIN
 
 .equ COM_IRQ_ADDR_ATTN   = COM_IRQ_ADDR_ATTN0
 .equ COM_IRQ_BIT_ATTN    = COM_IRQ_BIT_ATTN0
diff --git a/avr/devices/r04/test/main.asm b/avr/devices/r04/test/main.asm
index 53981c5..456d6e0 100644
--- a/avr/devices/r04/test/main.asm
+++ b/avr/devices/r04/test/main.asm
@@ -75,8 +75,8 @@
 ;#define MODULES_MOTION
 #define MODULES_NETWORK
 ;#define MODULES_TTYONUART1
-#define MODULES_COMONUART0
-;#define MODULES_COMONUART1
+;#define MODULES_COMONUART0
+#define MODULES_COMONUART1
 
 #define APPS_STATS
 #define APPS_NETWORK
@@ -133,16 +133,19 @@
         reti                          ; 20: TIM2_OVF (OVF2)   Timer/Counter2 Overflow
         reti                          ; 21: SPI               SPI Serial Transfer Complete
         reti                          ; 22: USART0_RXS        USART0 Rx Start
-        rjmp ComOnUart0_RxCharIsr     ; 23: USART0_RXC        USART0 Rx Complete
-        rjmp ComOnUart0_TxUdreIsr     ; 24: USART0_DRE        USART0 Data Register Empty
-        rjmp ComOnUart0_TxCharIsr     ; 25: USART0_TXC        USART0 Tx Complete
+;        rjmp ComOnUart0_RxCharIsr     ; 23: USART0_RXC        USART0 Rx Complete
+        reti                          ; 23: USART0_RXC        USART0 Rx Complete
+;        rjmp ComOnUart0_TxUdreIsr     ; 24: USART0_DRE        USART0 Data Register Empty
+        reti                          ; 24: USART0_DRE        USART0 Data Register Empty
+;        rjmp ComOnUart0_TxCharIsr     ; 25: USART0_TXC        USART0 Tx Complete
+        reti                          ; 25: USART0_TXC        USART0 Tx Complete
         reti                          ; 26: USART1_RXS        USART1 Rx Start
-;        rjmp ComOnUart1_RxCharIsr     ; 27: USART1_RXC        USART1 Rx Complete
-        reti                          ; 27: USART1_RXC        USART1 Rx Complete
-;        rjmp ComOnUart1_TxUdreIsr     ; 28: USART1_DRE        USART1 Data Register Empty
-        reti                          ; 28: USART1_DRE        USART1 Data Register Empty
-;        rjmp ComOnUart1_TxCharIsr     ; 29: USART1_TXC        USART1 Tx Complete
-        reti                          ; 29: USART1_TXC        USART1 Tx Complete
+        rjmp ComOnUart1_RxCharIsr     ; 27: USART1_RXC        USART1 Rx Complete
+;        reti                          ; 27: USART1_RXC        USART1 Rx Complete
+        rjmp ComOnUart1_TxUdreIsr     ; 28: USART1_DRE        USART1 Data Register Empty
+;        reti                          ; 28: USART1_DRE        USART1 Data Register Empty
+        rjmp ComOnUart1_TxCharIsr     ; 29: USART1_TXC        USART1 Tx Complete
+;        reti                          ; 29: USART1_TXC        USART1 Tx Complete
         reti                          ; 30: TWI               Two-Wire-Interface
         reti                          ; 31: RESERVED          reserved
 
@@ -171,11 +174,11 @@ firmwareStart:
 
 onSystemStart:
   ; set interface number for UART0
-  ldi r16, COMONUART0_IFACENUM
-  sts comOnUart0_iface+NET_IFACE_OFFS_IFACENUM, r16
+;  ldi r16, COMONUART0_IFACENUM
+;  sts comOnUart0_iface+NET_IFACE_OFFS_IFACENUM, r16
   ; set interface number for UART1
-;  ldi r16, COMONUART1_IFACENUM
-;  sts comOnUart1_iface+NET_IFACE_OFFS_IFACENUM, r16
+  ldi r16, COMONUART1_IFACENUM
+  sts comOnUart1_iface+NET_IFACE_OFFS_IFACENUM, r16
 
   ret
 ; @end
@@ -229,15 +232,8 @@ onMessageReceived:
 onAttnChangeIsr:
   push r15
     in r15, SREG
-    push r16
-;      inr r16, COM_ATTN1_INPUT
-;      sbrs r16, COM_ATTN1_PIN
-;        rcall ComOnUart1_HandleAttnChange  ; (none)
-
-;      inr r16, COM_ATTN0_INPUT
-;      sbrs r16, COM_ATTN0_PIN
-        rcall ComOnUart0_HandleAttnChange  ; (none)
-    pop r16
+      rcall ComOnUart1_HandleAttnChange  ; (none)
+;      rcall ComOnUart0_HandleAttnChange  ; (none)
     out SREG, r15
   pop r15
   reti
@@ -258,7 +254,7 @@ onAttnChangeIsr:
 ; ---------------------------------------------------------------------------
 ; defines for network interface
 
-.equ netInterfaceData = comOnUart0_iface
+.equ netInterfaceData = comOnUart1_iface
 ;.equ netInterfaceData2 = comOnUart1_iface