/**
\page cw_keyer CW Keyer Interface

The CW keyer is specifically designed to work with a DTR/RTS keyline to 
emulate the closure of a CW key.  Several transceivers have this capability 
built in to the hardware.  Some expose a separate keying port (FT-991A) and 
some share the CAT serial port (IC-7300).  A simple DTR/RTS keying circuit 
can also provide the h/w interface.  This one provides galvanic isolation:

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\image latex cw-keyer/DTR_keyer.png width=2.0in
\image html  cw-keyer/DTR_keyer.png
</center>

Open the keyer dialog with the main dialog menu item "Keyer"

<center>
\image latex cw-keyer/cwkeyer.png width=2.0in
\image html  cw-keyer/cwkeyer.png
</center>

<ul>
<li>WPM slider selects the keyer speed</li>
<li>Clear - clears the text in the transmit buffer</li>
<li>transmit text will marquee to the left as each character is transmitted</li>
<li>Send/Pause button toggles sending text.</li>
<li>macro buttons / function keys load transmit buffer with canned message</li>
<li>the transmit text buffer must have keyboard focus for character entry.  left click on the entry area to gain keyboard focus.</li>
</ul>

Tip for the function / macro buttons: 

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\image latex cw-keyer/cwkeyer_tooltip.png width=2.0in
\image html  cw-keyer/cwkeyer_tooltip.png
</center>

Control-left-click opens:

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\image latex cw-keyer/cwkeyer_editor.png width=2.0in
\image html  cw-keyer/cwkeyer_editor.png
</center>

A CQ macro with start/stop (ptt enable/disable): <pre>[CQ CQ DE W1HKJ K]</pre>

Config opens:

<center>
\image latex cw-keyer/cwkeyer_config.png width=2.0in
\image html  cw-keyer/cwkeyer_config.png
</center>

The DTR/RTS port can be either
<ul>
<li>shared with the CAT port</li>
<li>shared with the SEP port</li>
<li>shared with the AUX port</li>
<li>a unique serial port configured on this dialog</li>
<li>select either DTR or RTS for the keyline as required by h/w</li>
<li>Calibrate button sends standard "PARIS " word, WPM times.  Program 
measures actual time to transmit and sets compensation value.  Comp(msec) 
can be adjusted by user.</li>
</ul>

PTT delay is in milliseconds.  Enter a non-zero value to enable a delay 
between the PTT-on and the first CW keyline closure.  The same delay will 
be applied to the last CW keyline closure and PTT-off.

*/
