#    This is the channel Invert Input register which is DPP_CTRL  0x1n80  [16]
#       also called Pulse Polarity



    for {set i 0} {$i < $NumChans} {incr i} {
        variable Ch$i.Polarity 0
    }

proc GetPolarity {} {
   variable NumChans

    for {set i 0} {$i < $NumChans} {incr i} {
        variable Ch$i.Polarity
        set Ch$i.Polarity [ReadRegister Ch$i.Polarity]
    }
}

proc SetPolarity {w} {
   variable NumChans

      for {set i 0} {$i < $NumChans} {incr i} {

         if {$w < $NumChans && $w != $i} {continue}

         variable Ch$i.Polarity
         WriteRegister Ch$i.Polarity [set Ch$i.Polarity]
      }

}

    proc SavePolarity {} {
   variable NumChans

      for {set i 0} {$i < $NumChans} {incr i} {

           DBSetValue Ch$i.Polarity [ReadRegister Ch$i.Polarity]
      }
    }

    proc RestPolarity {} {
   variable NumChans

      for {set i 0} {$i < $NumChans} {incr i} {

           variable Ch$i.Polarity
           set Ch$i.Polarity  [DBGetValue Ch$i.Polarity]
           WriteRegister Ch$i.Polarity  [DBGetValue Ch$i.Polarity]
      }

    }

proc DrawPolarity {} {
   variable NumChans
   variable Name

   set html ""

   append html  "<p align=center>"
   append html  "<table cellpadding=0 cellspacing=0 border=1>"

   append html "<tr>"
   append html  "<td  align=center width=10%>Channel</td>"
   append html  "<td  align=center width=90%>Channel n Invert Input</td>"
   append html  "</tr>"

for {set i 0} {$i < $NumChans} {incr i} {

   append html "<tr>"
   append html "<td align=center width=10%>$i</td>"

   append html "<td align=center width=90%>"

   append html "<select name=P$i size=1 \
       onChange=\"click_CHSETTING(document.[set Name], 'Polarity', '$i', document.CHSETTINGS.P$i.value)\">"

   set j 0
   foreach item {positive  negative}  {
     set vl $j
     if {$vl == [set ::[set Name]::Ch$i.Polarity]} {
        append html "<option value=$vl selected>$item</option>"
     } else {
        append html "<option value=$vl>$item</option>"
     }
     incr j
   }

   append html "</select>"

   append html  "</td>"

   append html  "</tr>"
}
   append html  "</table>"

   append html  "</p>"

   return $html
}