Linux-Hams archive - October 1998: Re: soundmodem rx (DCD?) problem
Re: soundmodem rx (DCD?) problem
Marco Meijer (terhi.victor@logonet.com)
Thu, 01 Oct 1998 12:41:09 +0100
At 17:37 28/09/98 +0200, you wrote:
>Marco Meijer wrote:
>
>> When trying smdiag on one machine and sethdlc -i sm0 -c 20 on the other,
>> one of the machines gives a bad eye diagram. Volume levels seem fine, but
>> somehow it seems that this machine cannot do rx clock recovery (the upward
>> and downward flanks are not synchronised).
>
>You didn't say which mode you used. Some modes are sensitive to
>the lower cutoff freq. of the channel, notably fsk9600 (and to
>a somewhat lesser degree hapn4800). Maybe the caps of your
>soundcard are too small or the load resistance too low.
The mode I used is fsk9600. Thanks for the hint. I will take a look at the
caps and resistance. If you have a suggestion on how to fix that, I would
be gratefull.
>
>
>> supporting CPUID. Another complaint from the driver was that IRQ 7 would
>> be not free. The /proc/interrupts however says different.
>
>/proc/interrupts says which interrupts are _used_, not which ones
>are _occupied_. But nevertheless the detection mechanism is rather
>unstable and the message is an information only.
Maybe a stupid question, but what is the difference between used and
occupied in this context?
Marco