diff --git a/linak_ctrl.py b/linak_ctrl.py index 2d13f33..c4d171d 100755 --- a/linak_ctrl.py +++ b/linak_ctrl.py @@ -111,6 +111,10 @@ class LinakDevice: def __init__(self): self._dev = usb.core.find(idVendor=LinakDevice.VEND, idProduct=LinakDevice.PROD) + if not self._dev: + raise ValueError(f'Device {LinakDevice.VEND}:' + f'{LinakDevice.PROD:04d} ' + f'not found!') # detach kernel driver, if attached if self._dev.is_kernel_driver_active(0): @@ -188,7 +192,11 @@ class LinakDevice: def main(): - device = LinakDevice() + try: + device = LinakDevice() + except ValueError as ex: + sys.stderr.write(ex.args[0] + '\n') + sys.exit(1) parser = argparse.ArgumentParser('An utility to interact with USB2LIN06 ' 'device.')