I have recently bought five servos:
A. 2x HS-311 - standard servo
B. 1x HS-5625MG - digital high torque
C. 2x HS-7955TG - digital high torque
They are all new, in good condition and, accordingly to specifications, can travel 180º.
I am using the Arduino Mega 2560 and an external power supply, that can provide enough current. I'm running each servo at a time for now.
If I use the servo program from the examples, the A (HS-311) servo runs perfectly well, no problems at all (runs the 180º range). However, if I use servos B or C they will stay "rigid" at the middle angle, although the readings from the Knob are ok.
I think the problem isn't with the wire connection: I double checked everything and all the connections are similar to the ones I found in the web (grounds connected,...), plus the fact that the A servos work.
Then I tried another approach, using the myservo.writeMicroseconds(). Please check the program:
With this program the servo will run from about the 1000 us to 2000us, from 45º to 134º. I can not control them in the 0-44º or the 135-179º range. I used several values in the myservo.attach(2,min, max) but nothing as changed.
I could find some people facing the same trouble, but I couldn't find any solution. I really need the 180º range to work.
Could you please help me?
Thanks in advance!