Soundmodem/Linux/AX25 -- newbie confusion

[Cathryn Mataga http://junglevision.com]

Okay, here's my setup for bringing up the soundmodem.  The card is an
old SBPRO type card, that used to work with DOS games okay.

/usr/sbin/sethdlc -p -i sm0 mode sbc:afsk1200 io 0x220 irq 5 dma 1 pario 0x378
/usr/sbin/sethdlc -i sm0 -a txd slot 50 ppersist 128 half
/sbin/ifconfig sm0 hw ax25 KE6I-1 up

The /etc/axports looks like the following...

radio KE6I-1    1200    256     2       145.01 1200 baud AFSK

nrports and rsports are 0 length files.  

Now, at this point, if I do a call, it bugs out saying the radio port is
not initialized. But if I run the following.

/sbin/ifconfig sm0 44.4.28.50 netmask 255.255.255.0 up
/sbin/ifconfig sm0 broadcast 44.4.28.255 mtu 512
/sbin/route add -net 44.4.28.0 netmask 255.255.255.0 sm0

Then I can do...

%call radio n6cvx


It prints the 'GW4PTS AX25 -- Trying...' message.
Except, strange, I don't hear anything out of the PC speakers
when I hook speakers to the sound card output.  The TR never
keys either.  But, I'd think I'd hear something.  

Okay, so now I'm confused.  First, I why does setting up
the ip stuff affect call at all?  I thought that once I 
did...

/sbin/ifconfig sm0 hw ax25 KE6I-1 up

that AX25 should be alive -- right?  Should call even
know about ip?   I thought call was straight AX25
Maybe I don't understand something here.  

Should I have to do anything with the DCD output
from the printer port?   The radio I'm using is
the MFJ 8621, and I assume the soundmodem code
is cool with the unsquelched output -- err, I assume
it would have to be to work at 9600.  

I had another card that didn't work at all, and when
I tried to start it, I saw the error pop up on the
Linux console about no sound hardware at 0x220, but
this card I don't see this message.  So, it seems
that soundmodem sees something here.  I'm also a little
confused about the mixer settings, as I seem to be hearing
on the line output, the unsquelched hashshshsh sound coming
in the mic jack.  I thought there was a mixer setting to 
control this, but I can't seem to change this.  Maybe it
won't matter anyway, since when I transmit, it should shut
off the audio out, but it seems a little weird.  


Here's the 'ifconfig' section of my soundmodem.
 
sm0       Link encap:AMPR AX.25  HWaddr KE6I-1
          inet addr:44.4.28.50  Mask:255.255.255.0
          UP RUNNING  MTU:512  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          Interrupt:5 Base address:0x220 DMA chan:1


Why is TX packets 0 after trying to connect.  Shouldn't this
be clicking up?  
 
Is there any manual way to key the transmitter, so I can
check my TR switching cable?  Do I need to do anything about
any printer drivers, or is the TR switching able to handle
this.  At this point, I'm suspecting, though, that there's
another issue going on here.  

I have yet another sound card, an old geniune Sound Blaster
2.01 card, so maybe I'll give that a shot, to see if that's
the issue.