diff --git a/boards/px4/fmu-v5x/nuttx-config/nsh/defconfig b/boards/px4/fmu-v5x/nuttx-config/nsh/defconfig
index afed466ea2..53a5f54f0b 100644
--- a/boards/px4/fmu-v5x/nuttx-config/nsh/defconfig
+++ b/boards/px4/fmu-v5x/nuttx-config/nsh/defconfig
@@ -195,7 +195,7 @@ CONFIG_STM32F7_I2C_DYNTIMEO_STARTSTOP=10
 CONFIG_STM32F7_OTGFS=y
 CONFIG_STM32F7_PHYSR=16
 CONFIG_STM32F7_PHYSR_100MBPS=0x0
-CONFIG_STM32F7_PHYSR_FULLDUPLEX=0x01
+CONFIG_STM32F7_PHYSR_FULLDUPLEX=0x04
 CONFIG_STM32F7_PHYSR_MODE=0x04
 CONFIG_STM32F7_PHYSR_SPEED=0x2
 CONFIG_STM32F7_PROGMEM=y