11.7  piWebCAT operation - Sliders     Testing. See:  timing.disable


The state of the sliders is read for the current VFO (using the queue) at startup.

The slider position is set and the text value updated.

Normal operation  

When a slider is moved, the new value is sent to the radio when the mouse or finger is lifted.

Slider actions are write-only ... there is no feedback from the server.

The SliderArray in the client was loaded at startup. Its data is used when the slider value

is reset from the radio value at startup or changed by moving the slider.

When the slider is moved:

piWenCAT sends the appropriate message to the server.
On the server, the slider table in the database is interrogated to obtain information for a write
of slider data to the radio.

For Yaesu there is then no response from the radio. From Icom there is an OK response.

When the slider value is changed by slider movement or a reset from the radio

or a reset from the adjacent reset button, piWebCAT updates the numeric value text

to the right of the slider.
Fields in the SliderArray control the data presentation of this numeric text:
 - mult and divide can scale the result.
 - decpoint can insert a decimal point, eg: converting 3200Hz to 3.200kHz
 - offset can be used to shift the value, eg  0 to 100 displayed as -50 to + 50

 - lookup can invoke lookup table entries for non-linear cat > display relationships.

 - units can be displayed after the value.  

 - additionally, def is the CAT value applied by the slider's reset button.

If slider related values are altered on the radio, the corresponding slider states are not updated
on piWebCAT.  There are 27 sliders to repetitively read. Such reading would compromise the

more important repetitive tasks (ie: meter read  and frequency set)

However, piWebCAT provides a Reconnect button to resychronise piWebCAT's buttons and
sliders after operation of controls on the radio.