diff --git a/ports/stm32/main.c b/ports/stm32/main.c
index 4553a07e28..460a19ccb1 100644
--- a/ports/stm32/main.c
+++ b/ports/stm32/main.c
@@ -505,7 +505,7 @@ void stm32_main(uint32_t reset_mode) {
     rtc_init_start(false);
     #endif
     spi_init0();
-    #if MICROPY_HW_ENABLE_HW_I2C
+    #if MICROPY_PY_PYB_LEGACY && MICROPY_HW_ENABLE_HW_I2C
     i2c_init0();
     #endif
     #if MICROPY_HW_HAS_SDCARD
diff --git a/ports/stm32/modpyb.c b/ports/stm32/modpyb.c
index 3438b12e8e..6357aca946 100644
--- a/ports/stm32/modpyb.c
+++ b/ports/stm32/modpyb.c
@@ -227,7 +227,7 @@ STATIC const mp_rom_map_elem_t pyb_module_globals_table[] = {
 #if defined(MICROPY_HW_LED1)
     { MP_ROM_QSTR(MP_QSTR_LED), MP_ROM_PTR(&pyb_led_type) },
 #endif
-    #if MICROPY_HW_ENABLE_HW_I2C
+    #if MICROPY_PY_PYB_LEGACY && MICROPY_HW_ENABLE_HW_I2C
     { MP_ROM_QSTR(MP_QSTR_I2C), MP_ROM_PTR(&pyb_i2c_type) },
     #endif
     { MP_ROM_QSTR(MP_QSTR_SPI), MP_ROM_PTR(&pyb_spi_type) },
diff --git a/ports/stm32/pyb_i2c.c b/ports/stm32/pyb_i2c.c
index db09f688bf..33aaa48cbb 100644
--- a/ports/stm32/pyb_i2c.c
+++ b/ports/stm32/pyb_i2c.c
@@ -35,7 +35,7 @@
 #include "dma.h"
 #include "i2c.h"
 
-#if MICROPY_HW_ENABLE_HW_I2C
+#if MICROPY_PY_PYB_LEGACY && MICROPY_HW_ENABLE_HW_I2C
 
 /// \moduleref pyb
 /// \class I2C - a two-wire serial protocol
@@ -1065,4 +1065,4 @@ const mp_obj_type_t pyb_i2c_type = {
     .locals_dict = (mp_obj_dict_t*)&pyb_i2c_locals_dict,
 };
 
-#endif // MICROPY_HW_ENABLE_HW_I2C
+#endif // MICROPY_PY_PYB_LEGACY && MICROPY_HW_ENABLE_HW_I2C
diff --git a/ports/stm32/stm32_it.c b/ports/stm32/stm32_it.c
index db812958fb..a77802bfa4 100644
--- a/ports/stm32/stm32_it.c
+++ b/ports/stm32/stm32_it.c
@@ -776,6 +776,8 @@ void CAN2_SCE_IRQHandler(void) {
 }
 #endif
 
+#if MICROPY_PY_PYB_LEGACY
+
 #if defined(MICROPY_HW_I2C1_SCL)
 void I2C1_EV_IRQHandler(void) {
     IRQ_ENTER(I2C1_EV_IRQn);
@@ -831,3 +833,5 @@ void I2C4_ER_IRQHandler(void) {
     IRQ_EXIT(I2C4_ER_IRQn);
 }
 #endif // defined(MICROPY_HW_I2C4_SCL)
+
+#endif // MICROPY_PY_PYB_LEGACY