diff --git a/Spark_MultiDigitalPins.ubl b/Spark_MultiDigitalPins.ubl
index 0e3487b..a4f731f 100644
--- a/Spark_MultiDigitalPins.ubl
+++ b/Spark_MultiDigitalPins.ubl
@@ -1,6 +1,6 @@
-module Spark_MultiDigitalPins 'cat;Variables'
+module Spark_MultiDigitalPins Variables
 author 'Fatima Idrees'
-version 1 0 
+version 1 1 
 description ''
 
   spec ' ' 'RGBLED' 'RGBLED Pin _ R _ G _ B _' 'auto bool bool bool' 17 false false false
@@ -8,22 +8,39 @@ description ''
   spec 'r' 'Ultransonic Pin' 'Ultransonic Pin _' 'num' 17
 
 to RGBLED Pin Red Green Blue {
+  comment 'Created by Fatima Idrees'
   digitalWriteOp Pin Red
-  Pin += 1
-  digitalWriteOp Pin Green
-  Pin += 1
-  digitalWriteOp Pin Blue
+  digitalWriteOp (Pin + 1) Green
+  digitalWriteOp (Pin + 2) Blue
 }
 
 to RGBLED2 Pin Red Green Blue {
+  comment 'Created by Fatima Idrees'
   analogWriteOp Pin Red
-  Pin += 1
-  analogWriteOp Pin Green
-  Pin += 1
-  analogWriteOp Pin Blue
+  analogWriteOp (Pin + 1) Green
+  analogWriteOp (Pin + 2) Blue
 }
 
 to 'Ultransonic Pin' Input {
-  return ('distance (cm)' (Input + 1) (Input + 2))
+  comment 'Contributed by Joan Guillén and Josep Ferràndiz'
+  digitalWriteOp (Input + 1) false
+  waitMicros 2
+  digitalWriteOp (Input + 1) true
+  waitMicros 50
+  digitalWriteOp (Input + 1) false
+  local 'start' (microsOp)
+  waitUntil (or (not (digitalReadOp (Input + 2))) (((microsOp) - start) > 23320))
+  waitUntil (or (digitalReadOp (Input + 2)) (((microsOp) - start) > 23320))
+  if (((microsOp) - start) > 23320) {
+    comment 'Distance sensor not ready; return the last distance reading'
+    return _sr04_last
+  }
+  comment 'Pulse sent. Measure time until echo is detected.'
+  start = (microsOp)
+  waitUntil (or (not (digitalReadOp (Input + 2))) (((microsOp) - start) > 23320))
+  _sr04_last = ((10 * ((microsOp) - start)) / 583)
+  comment 'Leave some time for reverberations to die away.'
+  waitMillis 10
+  return _sr04_last
 }