diff --git a/sonoff/support_float.ino b/sonoff/support_float.ino
index 3809fd6ec..6e9379a53 100644
--- a/sonoff/support_float.ino
+++ b/sonoff/support_float.ino
@@ -17,93 +17,73 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#ifdef ARDUINO_ESP8266_RELEASE_2_3_0
+//#ifdef ARDUINO_ESP8266_RELEASE_2_3_0
 // Functions not available in 2.3.0
 
-// https://code.woboq.org/userspace/glibc/sysdeps/ieee754/flt-32/e_fmodf.c.html
 float fmodf(float x, float y)
 {
-  const float Zero[] = { 0.0, -0.0 };
+  // https://github.com/micropython/micropython/blob/master/lib/libm/fmodf.c
+  union {float f; uint32_t i;} ux = {x}, uy = {y};
+  int ex = ux.i>>23 & 0xff;
+  int ey = uy.i>>23 & 0xff;
+  uint32_t sx = ux.i & 0x80000000;
+  uint32_t i;
+  uint32_t uxi = ux.i;
 
-  int32_t hx = (int32_t)x;
-  int32_t hy = (int32_t)y;
-
-  int32_t sx = hx &0x80000000;                       // sign of x
-  hx ^= sx;                                          // |x|
-  hy &= 0x7fffffff;                                  // |y|
-
-  // purge off exception values
-  if ((0 == hy) || (hx >= 0x7f800000) || (hy > 0x7f800000)) { // y=0, or x not finite, or y is NaN
-    return (x * y) / (x * y);
+  if (uy.i<<1 == 0 || isnan(y) || ex == 0xff)
+    return (x*y)/(x*y);
+  if (uxi<<1 <= uy.i<<1) {
+    if (uxi<<1 == uy.i<<1)
+      return 0*x;
+    return x;
   }
-  if (hx < hy) { return x; }                         // |x|<|y| return x
-  if (hx == hy) { return Zero[(uint32_t)sx >> 31]; } // |x|=|y| return x*0
 
-  int32_t n, hz, ix, iy, i;
-  // determine ix = ilogb(x)
-  if (hx < 0x00800000) {                             // subnormal x
-    for (ix = -126, i = (hx << 8); i > 0; i <<= 1) { ix -=1; }
+  // normalize x and y
+  if (!ex) {
+    for (i = uxi<<9; i>>31 == 0; ex--, i <<= 1);
+    uxi <<= -ex + 1;
   } else {
-    ix = (hx >> 23) -127;
+    uxi &= -1U >> 9;
+    uxi |= 1U << 23;
   }
-
-  // determine iy = ilogb(y)
-  if (hy < 0x00800000) {                             // subnormal y
-    for (iy = -126, i = (hy << 8); i >= 0; i <<= 1) { iy -=1; }
+  if (!ey) {
+    for (i = uy.i<<9; i>>31 == 0; ey--, i <<= 1);
+    uy.i <<= -ey + 1;
   } else {
-    iy = (hy >> 23) -127;
+    uy.i &= -1U >> 9;
+    uy.i |= 1U << 23;
   }
 
-  // set up {hx,lx}, {hy,ly} and align y to x
-  if (ix >= -126) {
-    hx = 0x00800000 | (0x007fffff & hx);
-  } else {                                           // subnormal x, shift x to normal
-    n = -126 - ix;
-    hx = hx << n;
-  }
-  if (iy >= -126) {
-    hy = 0x00800000 | (0x007fffff & hy);
-  } else {                                           // subnormal y, shift y to normal
-    n = -126 - iy;
-    hy = hy << n;
-  }
-
-  // fix point fmod
-  n = ix - iy;
-  while (n--) {
-    hz = hx - hy;
-    if (hz < 0) {
-      hx = hx + hx;
-    } else {
-      if (hz == 0) {                                 // return sign(x)*0
-        return Zero[(uint32_t)sx >> 31];
-      }
-      hx = hz + hz;
+  // x mod y
+  for (; ex > ey; ex--) {
+    i = uxi - uy.i;
+    if (i >> 31 == 0) {
+      if (i == 0)
+        return 0*x;
+      uxi = i;
     }
+    uxi <<= 1;
   }
-  hz = hx - hy;
-  if (hz >= 0) { hx = hz; }
+  i = uxi - uy.i;
+  if (i >> 31 == 0) {
+    if (i == 0)
+      return 0*x;
+    uxi = i;
+  }
+  for (; uxi>>23 == 0; uxi <<= 1, ex--);
 
-  // convert back to floating value and restore the sign
-  if (0 == hx) {                                     // return sign(x)*0
-    return Zero[(uint32_t)sx >> 31];
+  // scale result up
+  if (ex > 0) {
+    uxi -= 1U << 23;
+    uxi |= (uint32_t)ex << 23;
+  } else {
+    uxi >>= -ex + 1;
   }
-  while (hx < 0x00800000) {                          // normalize x
-    hx = hx + hx;
-    iy -= 1;
-  }
-  if (iy >= -126) {                                  // normalize output
-    hx = ((hx - 0x00800000) | ((iy +127) << 23));
-    x = (float)(hx | sx);
-  } else {                                           // subnormal output
-    n = -126 - iy;
-    hx >>= n;
-    x = (float)(hx | sx);
-    x *= 1.0;                                        // create necessary signal
-  }
-  return x;                                          // exact output
+  uxi |= sx;
+  ux.i = uxi;
+  return ux.f;
 }
-#endif  // ARDUINO_ESP8266_RELEASE_2_3_0
+//#endif  // ARDUINO_ESP8266_RELEASE_2_3_0
 
 double FastPrecisePow(double a, double b)
 {