Cyril:
Thanks for the additional information on your USB-Serial Adapter. It appears
to use the MosChip - MCS7715 chipset, with which I am not familiar. I see
that it adds not just an RS-232 port, but also a parallel port.
I looked at the driver software bundle that comes with the adapter. It
appears that the Linux version (the other being Windows) of the driver must
be compiled before it is installed on the Pi, but I assume you have already
done that and installed it on the Pi.
Obviously, you have this adapter working with ADTPro/VSDrive, but that may
have more to do with the genius of David Schmidt than with the adapter and
its driver. Schmidt's error-correcting serial protocol seems able to
overcome a multitude of serial communications sins, even including lack of
proper handshaking.
{I wouldn't be surprised if the next version of ADTPro works with (2) soup
cans and a semi-taut string! - Please forgive my humor, Cyril}.
Anyway, at this point, my best suggestion is to try another brand of
USB-Serial adapter (plus its driver). The adapters using the FTDI chipset
always get the best reviews for reliability. In fact, David Schmidt
recommends the FTDI chipset <
http://retrofloppy.com/products.html#USBMAC>,
though Ivan (A2Cloud) Drucker reports good results with the genuine (not
cloned) Prolific chipset.
In each instance, the proper driver software will need to be installed on
the Pi.
I realize you would rather not buy something that may not fix the problem,
but the unreliability that you are experiencing _is_ caused by something and
I'm thinking that it is the adapter and/or its driver software. The internet
is filled with reports of USB-Serial adapter users experiencing serial
reliability issues due to the particular brand of chipset / driver used.
Unfortunately, there is inconsistency in their reviews.
I'll grant you that this is a frustrating problem, but we seem to have
exhausted the other possibilities.
Regards,
Hugh Hood
in article
3153c566-5416-4f38...@googlegroups.com, Cyril
Thibout at
in...@pulsar-informatique.com wrote on 3/23/15 1:23 PM: