Need to disable DTR on serial port

[Geoffrey Hausheer]

In an ongoing effort to get TzMax working, I've been fighting to get it
to talk to the device through the COM port.  The problem is that the
device (a wrist-watch...the program is used to download heart-rate data
from said watch) is very difficult to comunicate with.  In theory it is
quite simple: send a 'ping' command, wait for a response, then send the
'receive' command, and read the data.  In practice, getting the watch to
acknowledge the initial ping is challenging.  You need to repetitively
send the 'ping' at odd intervals until the watch responds.  Once it does,
it will respond to commands readily.

In any case, it turns out that one of the many requirements to get the
watch to respond is to have DTR disabled (done by setting fDtrControl =
DTR_CONTROL_DISABLE).  But apparently the default for linux is
DTR_CONTROL_ENABLE, and Wine will ignore any requests to change it
(DTR_CONTROL_HANDSHAKE being unimplemented as well)

I assume that driving the DTR line low is the trigger that tells the
watch to listen to the Rx line.

I am not sure if this is a Wine or Linux limitation, (as I have very
limited knowledge of serial protocols), so I was wondering if anyone had
any ideas for a suibtable workaround?

Thanks,
.Geoff