diff --git a/Makefile b/Makefile
index 610987b..3f3890e 100644
--- a/Makefile
+++ b/Makefile
@@ -104,6 +104,7 @@ OOCD_TARGET ?= stm32f1x
 
 # which USB CDC ACM port is used bu the device, so we can reset it
 ACMPORT = /dev/ttyACM0
+ACMPORT_EXISTS = $(shell [ -e $(ACMPORT) ] && echo 1 || echo 0 )
 
 # board specific USB DFU bootloader
 BOOTLOADERS = STM32duino-bootloader
@@ -172,8 +173,10 @@ flash-swd: $(BINARY).hex
 
 # reset device by setting the data width to 5 bis on the USB CDC ACM port
 reset:
+ifeq ($(ACMPORT_EXISTS), 1)
 	$(Q)stty --file $(ACMPORT) 115200 raw cs5
 	$(Q)sleep 0.5
+endif
 	
 flash-dfu: $(BINARY).bin reset
 	$(info flashing $(<) using DFU)