diff --git a/arch/tricore/include/tc397/irq.h b/arch/tricore/include/tc397/irq.h
index 108d59ee0e6..7b292b7e37e 100644
--- a/arch/tricore/include/tc397/irq.h
+++ b/arch/tricore/include/tc397/irq.h
@@ -34,6 +34,7 @@
 /****************************************************************************
  * Pre-processor Prototypes
  ****************************************************************************/
+#define TRICORE_UART_RX_IRQ      21
 
 /****************************************************************************
  * Public Types
diff --git a/arch/tricore/src/tc3xx/tc3xx_serial.c b/arch/tricore/src/tc3xx/tc3xx_serial.c
index e1eb8c0e817..e20433ccacb 100644
--- a/arch/tricore/src/tc3xx/tc3xx_serial.c
+++ b/arch/tricore/src/tc3xx/tc3xx_serial.c
@@ -179,7 +179,7 @@ static struct up_dev_s g_uart0priv =
   .uartbase  = &MODULE_ASCLIN0,
   .pins      = &g_uart0_pins,
   .baud      = CONFIG_UART0_BAUD,
-  .irq       = 21,
+  .irq       = TRICORE_UART_RX_IRQ,
 };
 
 static uart_dev_t g_uart0port =