[FADCA] USB to Com Port

[bud Thompson]

----- Original Message ----- 
From: "Chuck Hast" <wchast at gmail.com>
To: "Florida Amateur Digital Communication Association" 
<fadca at mailman.qth.net>
Sent: Thursday, September 07, 2006 10:03
Subject: Re: [FADCA] USB to Com Port


> On 9/7/06, Ray Cook <WD4SEN at bellsouth.net> wrote:
>> I am getting ready to put up some FPAC switches here in Clay county, I 
>> have
>> a computer with two USB ports and a card with 4 more USB ports.
>>
>> I need to find some adapters that go from USB to com port.
>>
>> I know there are several brands out there, and I have been told some do 
>> not
>> work well..so I am relying on your experiences for choices of brands.
>>
>> IF you have a source for these adaptors I would appreciate that 
>> information
>> too..
>>
>
> I am running a cheap $9 one, it is considered non-standard because it does
> not support the rs-232 control lines, but under kiss or 6pack those lines 
> do
> not appear to be a issue since the system is sending packets to the TNC,
> in the case of polled kiss or 6pack if the TNC can not accept a packet 
> because
> it is full or busy, it rejects the packet until it is ready for it so
> it has it's own
> internal flow control. As far as I can see from the kiss protocol there is 
> no
> control line support in the kiss code so even if they worked it does not 
> appear
> that they would be used. There was the ability to use the CD line in kiss 
> to
> signal to the kiss driver that the channel was busy but I was never able 
> to
> get it to work in a satisfactory way. 6pack took care of all that as
> it does it's
> own handling with control packets between the 6pack device and the 
> computer.
>
> Hey, if the cheap one does not make you happy try the next one up... This
> is ham radio, we gotta have fun, even with something as mundane as a
> USB device!!! I have gone through several layers of exchanges before I got
> what I was looking for, I used to feel guilty about doing exchanges but 
> some-
> where along the way I lost it... I guess I learned from my wife who is
> a fearless
> exchanger/returner...
>
> -- 
> Chuck Hast  -- KP4DJT --
>=

* * *

If the USB/Serial adapter does not have control lines it might not be 
satisfactory for simply checking out the TNC with the stock AX.25 EPROM  to 
be sure it works - using Windows or Linux terminal programs.  Once the AX.25 
EPROM has been replaced with 6PAC or BPQKISS - it may be difficult to run 
the TNC through the paces just to check it out to be sure it works okay.

That brings me to another point:  If it doesn't exist now - we should have 
some standard terminal program in the Linux mix just for this purpose -to 
check out TNCs before putting them into service on FPAC.  Another thing that 
would be good for those TNCs using KISS mode with the AX.25 EPROM 
(Kantronics XKISS, PK-96 KISS 0$B) is to have an UP routine and a DOWN 
routine - where those TNCs are put into the proper mode automatically when 
FPAC starts and returned to terminal mode when FPAC shuts down.

bud N0IA