initial commit

tcl/drivers/presshch.tcl

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+# humidity chamber pressure reading (4-20 mA with taskit RS232 ADC)
+
+namespace eval presshch {} {
+}
+
+proc stdConfig::presshch {} {
+  controller std "\r" 5
+
+  obj PressHumidityChamber rd
+  prop readcmd ":0400000003.."
+  prop update presshch::update
+  
+  kids Pressure {
+    node calib_min par 848
+    node calib_max par 1153
+  }
+}
+
+proc presshch::update {} {
+  if {[scan [sct result] ":0406%4x%4x%4x" a0 a1 a2] == 3} {
+    get_values [sct] calib_min calib_max
+    sct update [expr (($a2-$a0) * 25 / 65536. - 4) / 16. * ($calib_max - $calib_min) + $calib_min]
+  } else {
+    error "bad result: [sct result]"
+  }
+  return idle
+}
+