ESC claibration problem

[GoogleCodeExporter]

I am trying to build a quadcopter but i am facing problem in calibration of 
ESC. I have 4in 1 EMAX ESC. I am using Arduino UNO to calibrate the ESC. My 
code is:

#include <Servo.h>

Servo esc;
int potpin = 0;// Pot pin
int val=0; 
void setup()
{
  esc.attach(9);// ESC attach to pin no 9
  }
void loop()
{
  val = analogRead(potpin);
  val = map(val, 0, 1023, 0, 179);
 esc.write(val);
  }
by using this code i have calibrated 2 ESCs (esc1 and esc2) out of 4 and they 
are working fine. but other 2 ESCs(esc 3 and esc4) are not calibrating properly 
although the ESC is giving the calibration confirmation tone but motors are not 
rotating.
my procedure is-
1- throttle the pot at full.
2- connect the li po and turn on the esc
3- after exact beep sending the minimum signal to ESC (by throttling pot to 
lowest position).
4- certain beeps come and finally calibration confirmation beep comes and ESC 
has calibrated. but motors are not rotating
Plz help me .

Original issue reported on code.google.com by amits0...@gmail.com on 27 Nov 2014 at 12:54

[GoogleCodeExporter]

just edit 
val= map(val, 0, 1023, 40, 179)

Cz some esc cant detect servo value below 40

Original comment by nabils...@gmail.com on 1 Mar 2015 at 7:16