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10 years, 6 months ago.
servo motor connected to Mbed NXP LPC1678
Hi there
I've connected the servo motor and loaded this code. I am not so good in programming so I picked up one code and compiled it. It compiled correctly but servo motor is not turning. Could you please tell me what is wrong? 
1 Answer
10 years, 6 months ago.
Is there 5 volts DC on the pins that power the servo (where the black and red cables are connected)? And is p21 on the mbed connected to the servo cable? (You can easily measure this by using a multimeter, if you have this available).
Also, the 5V USB does not have the capacity to power servos (the mbed will most likely reset if you try to run a large servo via usb power). You probably have to have an 5V external power supply of some sort.
It would be really helpful if you would name the baseboard that the mbed is connected to.
Looking at his picture it looks to me like the servo is connected to p21-p22-p23.
@Ohlzas: Ground should be connected to ground, power to 5V (small servos should run from USB without (much) load, but this is a fairly large one, you can try it without load, but external power supply is better, in which case the grounds of USB power and external power should be shorted). And then signal to p21.
posted by 30 Sep 2013