diff --git a/avr/devices/c01/defs.asm b/avr/devices/c01/defs.asm
index 21fed9d..847b439 100644
--- a/avr/devices/c01/defs.asm
+++ b/avr/devices/c01/defs.asm
@@ -67,6 +67,12 @@
 .equ COM_BIT_LENGTH      = 52000 ; 104000ns=9600, 52000ns=19200, 26000ns=38400
 .equ COM_HALFBIT_LENGTH  = 26000 ; see https://de.wikipedia.org/wiki/Universal_Asynchronous_Receiver_Transmitter
 
+.equ COM_DATA_DDR       = DDRD   ; use RX pin
+.equ COM_DATA_INPUT     = PIND
+.equ COM_DATA_OUTPUT    = PORTD
+.equ COM_DATA_PIN       = PORTD0
+
+
 .equ COM_ATTN_DDR       = DDRD
 .equ COM_ATTN_INPUT     = PIND
 .equ COM_ATTN_OUTPUT    = PORTD
diff --git a/avr/devices/c01/main/main.asm b/avr/devices/c01/main/main.asm
index ba8eb22..8ff8d48 100644
--- a/avr/devices/c01/main/main.asm
+++ b/avr/devices/c01/main/main.asm
@@ -61,6 +61,8 @@
 #define MODULES_NETWORK
 ;#define MODULES_COMONUART0
 #define MODULES_UART_HW
+;#define MODULES_UART_BITBANG
+
 #define MODULES_SPI_HW
 #define MODULES_ILI9341
 ;#define MODULES_FONT_8X8
@@ -221,6 +223,6 @@ onEveryLoop:
 ; defines for network interface
 
 .equ netInterfaceData = netUartIface
-
+;.equ netInterfaceData = uart_bitbang_iface