Updates & MKISS on USB serial?

Updates & MKISS on USB serial?

[Robert Jenkins]

Hi,

Can anyone tell me if USB serial adaptors will work OK with the standard
AX25 serial port stuff - Kissattach / MKISS??
(For KISS TNC connection.)

If so, any advice on make or type?


Are there any problems with running the AX25 tools etc. on RHEL3 (Whitebox)
etc?? I'm using that on another machine and it seems to run well.

My existing BBS / Node setup is running RH 7.2 (with kernel 2.4.19) which is
now unsupported & I think it's about time for an upgrade.
The machine I want to transfer it to is short of serial ports & has no spare
bus slots, hence the USB question.

Are any extra patches needed on the current Redhat 2.4.21 kernel, assuming I
get all the latest AX25 Tools & Libs etc?

Any comments appreciated.

Thanks,
Robert Jenkins, G8TBF.

Re: Updates & MKISS on USB serial?

[Wilbert Knol]

> Can anyone tell me if USB serial adaptors will work OK with the standard
> AX25 serial port stuff - Kissattach / MKISS??
> (For KISS TNC connection.)

Yes. It works great.

> If so, any advice on make or type?

I use a Keyspan USA-49W, a USB hub with 4 serial ports.

http://www.keyspan.com

Best piece of kit I've bought for the notebook.  It runs a KISS TNC, as well 
as a CI-V rig interface (the excellent Hamlib rig control libraries). In 
addition, the hub keys the radio on the 3rd port using CWdaemon.

I have also successfully used a USC-1000  USB to 1 serial port 'dongle'. It 
uses the FTDI chipset.

Both gizmos are supported by Linux, although you may have to recompile the 
kernel in order to get the drivers. Suggest you use kernel 2.4.22.. there 
were several USB improvements over 2.4.21. Check the 2.4.22 ChangeLog.

One drawback of USB: as with most modern hardware, the connectors aren't well 
engineered. The plug-socket combination appears to have intermittents on the 
shield and the lift in QRM is noticable. How this USB stuff ever passed basic 
EMC tests is beyond me.


Wilbert, ZL2BSJ

Re: Updates & MKISS on USB serial?

[Ralf Baechle DL5RB]

On Wed, Jun 23, 2004 at 08:45:44AM +0100, Robert Jenkins wrote:

> Can anyone tell me if USB serial adaptors will work OK with the standard
> AX25 serial port stuff - Kissattach / MKISS??
> (For KISS TNC connection.)
> 
> If so, any advice on make or type?

In theory - I'm only using real serial interfaces - that should work for
6pack and mkiss.

What won't work are bitbanging interfaces like some Baycom modems that
rely on the existence of a "real" 8250 or similar..

  Ralf

Re: Updates & MKISS on USB serial?

[Dave Platt]

> Can anyone tell me if USB serial adaptors will work OK with the standard
> AX25 serial port stuff - Kissattach / MKISS??
> For KISS TNC connection.)
>  
> If so, any advice on make or type?

In principal, they should work fine - the TNC should not see any
difference.

In practice, the success rate may depend on the specific model,
and on how well the Linux driver for the device is written.

I've been using one of the little KISS-only "TNC-X" TNCs,
which I purchased with the USB option - a DLP-USB232M module
which plugs into the TNC board.  Under Linux 2.4.22 (and, I
think, 2.4.24 as well), the results were a bit like the old
doggerel:

   "There once was a pretty little girl
    with curls down over her forehead.
    When she was good, she was very very good,
    and when she was bad, she was horrid."

The Linux driver for this particular USB dongle/adapter,
and/or the Linux USB-serial and USB stack in general, seems
to have some significant problems with hot unplugging.  If
the device is in use (e.g. kissattach is attached to it),
and the device or its hub is unplugged, there's a pretty
high likelyhood of a single-thread kernel panic which leaves
the USB stack in a boggle-brained state.  The device won't
be "seen" again properly until the USB stack is restarted...
and because it boggled out in a semi-busy state, there seems
to be no way to unload and reload the modules without actually
rebooting the system.

As long as I was careful not to unplug, it worked fine, but
unplugging even once by accident would necessitate rebooting
the system, and that's just not acceptable.  So, I unplugged
the module from the TNC-X board, and switched it back to
RS-232 serial mode, which works just fine.

There may have been improvements in the Linux kernel's
handling of hot unplugging of serial USB devices in more
recent kernels, and it's possible that other serial dongles
don't exhibit this problme.  I haven't been motivated to try 
to find out, as the serial mode on this TNC works reliably and as
I have plenty of spare serial ports on the system in question.