Hello,
I've been able to get swr readings from my ts570 using hyper terminal 
(on windows xp) and a serial cable connecting the rig to a com port.  
Below is a quick explanation of the process.

First, you need to connect your rig to a spare com port on your pc.  
Unfortunately, the kenwood needs a male connector which means you need 
to find a 9-pin serial cable with male connectors on each end or use 
some gender changer adapters.  

Next, turn on your rig and bring up HyperTerminal and set up a new 
connection.  You'll need to select the com port and port settings (9600 
baud, n, 8, 1).  

Now you should be ready to test your connection.  They kenwood has a 
bunch of commands for controlling the rig which can be found in the 
appendix to the manual.  The thing to remember is that each command ends 
with a semi-colon ";" rather than a new-line or <enter> key.  

The first thing to try is ask the rig to tell you the current vfo 
frequency.  The command for this is
fa;
You should see a response on your screen.   If not, you probably have a 
bad connection between your computer and the rig.

Next set to power level to 5 watts by entering
pc005;pc;
The first commands sets the power level while the second reads and 
displays the power level.

Next, tell the rig that you will be reading the swr meter by typing
rm1;
You will not get a response from this command.

Next, put your rig in am mode and press the send button.  While 
transmitting an am carrier you can read the swr by typing
rm;
You should see something like  rm1003 on your screen.  This would 
indicate a 3:1 swr.  You can change frequencies while in transmit mode 
and take readings to determine the approximate point of lowest swr.  

One thing I forgot to mention is that you probably want to turn off your 
antenna tuner before measuring.  Otherwise you will not get a true 
reading of the antenna.  On the 570 this is done by quickly tapping the 
att button.  You'll hear a click indiacting that the tuner is 
temporarily disabled.

I haven't used the kenwood software, but my guess is that they display 
the meters as graphics which won't be read by a screenreader.

Perhaps some of you have discovered other ways to obtain swr readings 
(other than using a tw1).

73
Chris w1gm