diff --git a/libraries/AP_HAL_ChibiOS/hwdef/common/stm32h7_type2_mcuconf.h b/libraries/AP_HAL_ChibiOS/hwdef/common/stm32h7_type2_mcuconf.h
index fba12421e32778..8c02c8378466cf 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/common/stm32h7_type2_mcuconf.h
+++ b/libraries/AP_HAL_ChibiOS/hwdef/common/stm32h7_type2_mcuconf.h
@@ -112,7 +112,7 @@
 #if STM32_HSECLK == 0U
 // no crystal, this gives 400MHz system clock
 #define STM32_HSE_ENABLED                   FALSE
-#define STM32_HSI_ENABLED                   TRUE
+#define STM32_HSI_ENABLED                   TRUE // HSI is 64MHz
 #define STM32_PLL1_DIVM_VALUE               32
 #define STM32_PLL2_DIVM_VALUE               32
 #define STM32_PLL3_DIVM_VALUE               32
@@ -125,8 +125,8 @@
 #define STM32_HSE_ENABLED                   TRUE
 #define STM32_HSI_ENABLED                   FALSE
 #define STM32_PLL1_DIVM_VALUE               4
-#define STM32_PLL2_DIVM_VALUE               8
-#define STM32_PLL3_DIVM_VALUE               8
+#define STM32_PLL2_DIVM_VALUE               4
+#define STM32_PLL3_DIVM_VALUE               4
 #define STM32_PLLSRC                        STM32_PLLSRC_HSE_CK
 #define STM32_CKPERSEL                      STM32_CKPERSEL_HSE_CK
 
@@ -135,8 +135,8 @@
 #define STM32_HSE_ENABLED                   TRUE
 #define STM32_HSI_ENABLED                   FALSE
 #define STM32_PLL1_DIVM_VALUE               8
-#define STM32_PLL2_DIVM_VALUE               16
-#define STM32_PLL3_DIVM_VALUE               16
+#define STM32_PLL2_DIVM_VALUE               8
+#define STM32_PLL3_DIVM_VALUE               8
 #define STM32_PLLSRC                        STM32_PLLSRC_HSE_CK
 #define STM32_CKPERSEL                      STM32_CKPERSEL_HSE_CK
 
@@ -144,24 +144,7 @@
 #error "Unsupported HSE clock"
 #endif
 
-#if STM32_HSECLK == 0U
-// no crystal
-#define STM32_PLL1_DIVN_VALUE               260
-#define STM32_PLL1_DIVP_VALUE               1
-#define STM32_PLL1_DIVQ_VALUE               6
-#define STM32_PLL1_DIVR_VALUE               4
-
-#define STM32_PLL2_DIVN_VALUE               200
-#define STM32_PLL2_DIVP_VALUE               3
-#define STM32_PLL2_DIVQ_VALUE               3
-#define STM32_PLL2_DIVR_VALUE               2
-
-#define STM32_PLL3_DIVN_VALUE               96
-#define STM32_PLL3_DIVP_VALUE               1
-#define STM32_PLL3_DIVQ_VALUE               2
-#define STM32_PLL3_DIVR_VALUE               4
-
-#elif (STM32_HSECLK == 8000000U) || (STM32_HSECLK == 16000000U)
+#if (STM32_HSECLK == 0U) || (STM32_HSECLK == 8000000U) || (STM32_HSECLK == 16000000U)
 // common clock tree for multiples of 8MHz crystals
 #ifdef HAL_CUSTOM_MCU_CLOCKRATE
 #if HAL_CUSTOM_MCU_CLOCKRATE == 520000000
@@ -185,7 +168,7 @@
 
 #define STM32_PLL2_DIVN_VALUE               400
 #define STM32_PLL2_DIVP_VALUE               3
-#define STM32_PLL2_DIVQ_VALUE               3
+#define STM32_PLL2_DIVQ_VALUE               10 // 80MHz for FDCAN
 #define STM32_PLL2_DIVR_VALUE               2
 
 #define STM32_PLL3_DIVN_VALUE               192
@@ -256,7 +239,7 @@
 #define STM32_FMCSEL                        STM32_OCTOSPISEL_HCLK
 
 #define STM32_SWPSEL                        STM32_SWPSEL_PCLK1
-#define STM32_FDCANSEL                      STM32_FDCANSEL_PLL1_Q_CK
+#define STM32_FDCANSEL                      STM32_FDCANSEL_PLL2_Q_CK
 #define STM32_DFSDM1SEL                     STM32_DFSDM1SEL_PCLK2
 #define STM32_SPDIFSEL                      STM32_SPDIFSEL_PLL1_Q_CK
 #define STM32_SPI45SEL                      STM32_SPI45SEL_PCLK2
diff --git a/libraries/AP_HAL_ChibiOS/hwdef/scripts/STM32H723xx.py b/libraries/AP_HAL_ChibiOS/hwdef/scripts/STM32H723xx.py
index 5e99778a478254..be27a55cdf47d2 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/scripts/STM32H723xx.py
+++ b/libraries/AP_HAL_ChibiOS/hwdef/scripts/STM32H723xx.py
@@ -34,13 +34,13 @@
     ],
 
     'EXPECTED_CLOCK' : 400000000,
-
+    
 	'EXPECTED_CLOCKS' : [
-		('STM32_SYS_CK',	400000000),
-		('STM32_QSPICLK', 	200000000),
-		('STM32_SDMMC1CLK',  80000000),
+        ('STM32_SYS_CK',	400000000),
+		('STM32_OSPICLK', 	200000000),
+        ('STM32_SDMMC1CLK',  66666666),
 		('STM32_SPI45CLK',  100000000),
-		('STM32_FDCANCLK',   80000000),
+        ('STM32_FDCANCLK',   80000000),
 	],
 
     # this MCU has M7 instructions and hardware double precision
diff --git a/libraries/AP_HAL_ChibiOS/hwdef/scripts/STM32H730xx.py b/libraries/AP_HAL_ChibiOS/hwdef/scripts/STM32H730xx.py
index 9ef0393b84e446..00eac5105c143b 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/scripts/STM32H730xx.py
+++ b/libraries/AP_HAL_ChibiOS/hwdef/scripts/STM32H730xx.py
@@ -69,7 +69,7 @@
 		('STM32_OSPICLK', 	200000000),
 		('STM32_SDMMC1CLK',  86666666),
 		('STM32_SPI45CLK',  100000000),
-		('STM32_FDCANCLK',   86666666),
+        ('STM32_FDCANCLK',   80000000),
 	],
 
     # this MCU has M7 instructions and hardware double precision