diff --git a/demos/ARMCM4-STM32F407-DISCOVERY/main.c b/demos/ARMCM4-STM32F407-DISCOVERY/main.c
index cc12871d4..ab126427b 100644
--- a/demos/ARMCM4-STM32F407-DISCOVERY/main.c
+++ b/demos/ARMCM4-STM32F407-DISCOVERY/main.c
@@ -201,7 +201,7 @@ int main(void) {
 
   /*
    * Activates the serial driver 1 using the driver default configuration.
-   * PA2(TX) and PA3(RX) are routed to USART1.
+   * PA2(TX) and PA3(RX) are routed to USART2.
    */
   sdStart(&SD2, NULL);
   palSetPadMode(GPIOA, 2, PAL_MODE_ALTERNATE(7));