diff --git a/src/machine/machine_stm32f103.go b/src/machine/machine_stm32f103.go
index 86ed1411..55e57995 100644
--- a/src/machine/machine_stm32f103.go
+++ b/src/machine/machine_stm32f103.go
@@ -358,7 +358,7 @@ func (spi SPI) getBaudRate(config SPIConfig) uint32 {
 	default:
 		conf |= stm32.SPI_CR1_BR_Div256
 	}
-	return conf
+	return conf << stm32.SPI_CR1_BR_Pos
 }
 
 // Configure SPI pins for input output and clock