diff --git a/javascript/JZZ.js b/javascript/JZZ.js
index 8296970..fe2b567 100644
--- a/javascript/JZZ.js
+++ b/javascript/JZZ.js
@@ -3134,6 +3134,9 @@
     umpFineTuning: function(g, c, x, y, z, w) {
       return _helperGC.umpRPN(g, c, 0, 1, x, y, z, w);
     },
+    umpFineTuningF: function(g, c, x) {
+      return _helperGC.umpFineTuning(g, c, MIDI.to32b(_01((x % 1 + 1) / 2, x)));
+    },
     umpCoarseTuning: function(g, c, n) {
       return [0x40 + _4b(g), 0x20 + _ch(c), 0, 2, _7b(n) * 2, 0, 0, 0];
     },
diff --git a/test/common.js b/test/common.js
index 2dd3c76..6c9bdda 100644
--- a/test/common.js
+++ b/test/common.js
@@ -1073,6 +1073,11 @@ describe('UMP messages', function() {
   });
   it('umpFineTuning', function() {
     assert.equal(JZZ.UMP.umpFineTuning(1, 2, 0x80000000).toString(), '41220001 80000000 -- Registered Controller: Fine Tuning');
+    assert.equal(JZZ.UMP.umpFineTuningF(1, 2, -.9999999999).toString(), '41220001 00000000 -- Registered Controller: Fine Tuning');
+    assert.equal(JZZ.UMP.umpFineTuningF(1, 2, -.5).toString(), '41220001 40000000 -- Registered Controller: Fine Tuning');
+    assert.equal(JZZ.UMP.umpFineTuningF(1, 2, 0).toString(), '41220001 80000000 -- Registered Controller: Fine Tuning');
+    assert.equal(JZZ.UMP.umpFineTuningF(1, 2, .5).toString(), '41220001 c0000000 -- Registered Controller: Fine Tuning');
+    assert.equal(JZZ.UMP.umpFineTuningF(1, 2, .9999999999).toString(), '41220001 ffffffff -- Registered Controller: Fine Tuning');
   });
   it('umpCoarseTuning', function() {
     assert.equal(JZZ.UMP.umpCoarseTuning(1, 2, 3).toString(), '41220002 06000000 -- Registered Controller: Coarse Tuning');