diff --git a/libraries/AP_HAL_ChibiOS/hwdef/H757I_EVAL/hwdef.dat b/libraries/AP_HAL_ChibiOS/hwdef/H757I_EVAL/hwdef.dat
index 469cf96f1e035..d6fcde170ad97 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/H757I_EVAL/hwdef.dat
+++ b/libraries/AP_HAL_ChibiOS/hwdef/H757I_EVAL/hwdef.dat
@@ -24,7 +24,7 @@ APJ_BOARD_ID 146
 FLASH_SIZE_KB 2048
 
 # setup build for a peripheral firmware
-# env AP_PERIPH 1
+env AP_PERIPH 1
 
 # bootloader is installed at zero offset
 FLASH_RESERVE_START_KB 128