CHIRP

When I try to download data from the radio, following all the steps, just after pressing V/M to start transmitting, the download fails with the following error:

ERROR: -- Exception: --
ERROR: Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/chirp/ui/clone.py", line 249, in run
    self.__radio.sync_in()
  File "/usr/lib/python2.7/site-packages/chirp/drivers/ft7800.py", line 327, in sync_in
    self.check_checksums()
  File "/usr/lib/python2.7/site-packages/chirp/drivers/yaesu_clone.py", line 229, in check_checksums
    if checksum.get_existing(self._mmap) != \
  File "/usr/lib/python2.7/site-packages/chirp/drivers/yaesu_clone.py", line 175, in get_existing
    return ord(mmap[self._address])
TypeError: ord() expected a character, but string of length 0 found

ERROR: ----------------
ERROR: Clonado fallido: ord() expected a character, but string of length 0 found
ERROR: --- Exception Dialog: ord() expected a character, but string of length 0 found ---
ERROR: None

ERROR: ----------------------------

The cable works as I downloaded the data a moment ago using the FTB7900 program under wine.

System is Arch Linux using Python 2.7.12