diff --git a/libraries/AP_HAL_ChibiOS/hwdef/f303-MatekGPS/hwdef.dat b/libraries/AP_HAL_ChibiOS/hwdef/f303-MatekGPS/hwdef.dat
index 7bd29195bf..b63e465a20 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/f303-MatekGPS/hwdef.dat
+++ b/libraries/AP_HAL_ChibiOS/hwdef/f303-MatekGPS/hwdef.dat
@@ -22,7 +22,7 @@ define HAL_WATCHDOG_ENABLED_DEFAULT true
 # crystal frequency
 OSCILLATOR_HZ 8000000
 
-define CH_CFG_ST_FREQUENCY 100000
+define CH_CFG_ST_FREQUENCY 1000
 define CH_CFG_ST_TIMEDELTA 0
 
 # assume the 256k flash part for now
@@ -83,7 +83,6 @@ define IO_THD_WA_SIZE      512
 
 define HAL_NO_GCS
 define HAL_NO_LOGGING
-define HAL_NO_MONITOR_THREAD
 
 define HAL_MINIMIZE_FEATURES 0
 
@@ -127,8 +126,8 @@ PA2 USART2_TX USART2 SPEED_HIGH NODMA
 PA3 USART2_RX USART2 SPEED_HIGH NODMA
 
 # USART3, for MSP
-PB10  USART3_TX USART3 SPEED_HIGH NODMA
-PB11  USART3_RX USART3 SPEED_HIGH NODMA
+PB10  USART3_TX USART3 SPEED_HIGH
+PB11  USART3_RX USART3 SPEED_HIGH
 
 # use a default node ID so this works with MSP only
 define HAL_CAN_DEFAULT_NODE_ID 112
@@ -150,11 +149,12 @@ define HAL_PERIPH_ENABLE_AIRSPEED
 define HAL_PERIPH_ENABLE_RANGEFINDER
 define HAL_PERIPH_ENABLE_MSP
 
-# allow for rangefinder to be plugged in on "MSP" port
-define HAL_PERIPH_ADSB_PORT_DEFAULT 1
-define HAL_PERIPH_ENABLE_ADSB
-
+# setup for MSP
 define HAL_MSP_ENABLED 1
+define AP_PERIPH_MSP_PORT_DEFAULT 2
+
+# disable rangefinder by default
+define AP_PERIPH_RANGEFINDER_PORT_DEFAULT -1
 
 # the M8 GPS is good at 10Hz, but the M9 is better at 5Hz,
 # so stick to 5Hz as the firmware is shared