diff --git a/ports/stm32/modmachine.h b/ports/stm32/modmachine.h
index 0c776280b4..409c552e6c 100644
--- a/ports/stm32/modmachine.h
+++ b/ports/stm32/modmachine.h
@@ -29,7 +29,6 @@
 #include "py/obj.h"
 
 extern const mp_obj_type_t machine_adc_type;
-extern const mp_obj_type_t machine_timer_type;
 extern const mp_obj_type_t machine_i2c_type;
 extern const mp_obj_type_t machine_i2s_type;
 extern const mp_obj_type_t machine_spi_type;