This might get long, so here is the short story:

I'm attempting to ssh into a Raspberry Pi and then use the USB port to
communicate directly with a Cisco switch using a usb to serial adapter and
an RJ-45 console cable.  This causes crashes that are repairable by
powering off the Pi and rebooting.

Here are the details:

*Hardware:*
RaspberryPi, version 2 (512MB RAM)
16BG class10 micro SD in an SD converter
USB to serial adapter on /dev/ttyUSB0
Serial to console cable
Cisco 2950 Switch

*Software:*
OS - Rasbian [*note: I've run `apt-get update` but not `apt-get updrage` at
this point due to time considerations)*
SSH  - installed and enabled
Minicom - installed and set to the Specs specified by Cisco for console
communication (9600 8N)

*What has happened:*
I've been able to ssh in and create a new user and such.  No Problems here.
 After installing minicom, I have had only spotty success with seeing any
output from the Cisco Switch.

I have been able to communicate with it twice, but both have ended with the
Pi crashing.  At first my computer reports that `the host is not
responding.` Then I eventually get `The host is down`.  This is when I have
to reboot.

However, those two successful attempts are only two on *many *attempts.
There have been Many times (at least 10) when I ssh in, run `sudo minicom`,
and once minicom is running, I get no response from the interface.  The
`^a` to get to the menu works and I can exit minicom.

During these times when minicom is not producing output from the switch,
there have also been the same crashes as explained earlier.

*Questions:
*
1 - Have you had any experience with serial comunication over the USB port
on a Raspberry Pi?  What are your results?

2 - As I said earlier, I haven't run `sudo apt-get upgrade`.  Do you think
this will solve the crashing issues?  How about the non-responsiveness in
minicom?

3 - I've tried several different levels of overclock.  Do you think this
timing has anything to do with the serial communication flakiness?

4 - Minicom specific issue:  What's the difference between "exit and reset"
and "exit without reset"?  I'm guessing it has something to do with keeping
the switch output in a buffer until I come back, but I haven't had enough
successful communication attempts to know  for sure.  If I exit minicom the
wrong way, will it bork future communication attempts?

Thanks,

Al
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