[chirp_users] Retevis RT24 download problem

[Marc Eberhard]

Hi,

I'm trying to use Chirp with an RT24 and I'm getting the following
error when trying to download the radio memory:

ERROR: ----------------------------
ERROR: -- Exception: --
ERROR: Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/chirp/ui/clone.py", line 256, in run
    self.__radio.sync_in()
  File "/usr/lib/python2.7/site-packages/chirp/drivers/radioddity_r2.py",
line 364, in sync_in
    data = do_download(self)
  File "/usr/lib/python2.7/site-packages/chirp/drivers/radioddity_r2.py",
line 270, in do_download
    block = _r2_read_block(radio, addr, radio._block_size)
  File "/usr/lib/python2.7/site-packages/chirp/drivers/radioddity_r2.py",
line 223, in _r2_read_block
    raise errors.RadioError("Failed to read block at %04x" % block_addr)
RadioError: Failed to read block at 0008

ERROR: ----------------
ERROR: Clone failed: Failed to read block at 0008
ERROR: --- Exception Dialog: Failed to read block at 0008 ---
ERROR: None

It's not always block 0008, sometimes others. Sounds like a timing
issue that hits often enough to make a download impossible, but not
always at the exact same block. The cable is:

[  590.992784] usb 1-11: new full-speed USB device number 11 using xhci_hcd
[  591.133874] usb 1-11: New USB device found, idVendor=067b,
idProduct=2303, bcdDevice= 3.00
[  591.133880] usb 1-11: New USB device strings: Mfr=1, Product=2,
SerialNumber=0
[  591.133884] usb 1-11: Product: USB-Serial Controller
[  591.133887] usb 1-11: Manufacturer: Prolific Technology Inc.
[  591.136816] pl2303 1-11:1.0: pl2303 converter detected
[  591.138128] usb 1-11: pl2303 converter now attached to ttyUSB0

I bought the cable from eBay:

https://www.ebay.co.uk/itm/USB-Programming-Cable-for-Retevis-H777-RT22-RT24-Baofeng-888S-UV5R-Kenwood-Radio/163835755203

As far as I can tell it looks genuine. The PC is a current Arch Linux system.

Reading the docs suggests that the cable might be to blame. Before
contacting the seller about it I just wanted to check if this is the
expected failure mode for the cable or would it not work at all if it
were using a copycat pl2303?

If this is a timing issue can I slow Chirp down somehow to see if that
makes a difference? E.g. let it sleep for a bit between downloading
blocks to give the radio/cable some time to recover?

All suggestions and comments welcome!

Thanks,
Marc