creating PWM using PIC

[Transistorman]

hi
i want to controlling my servo or to test it
i want it moving clockwise 360 degress then back anti clockwise 360 degress
im using 16 mhz resonator
how to do it ?

 

[Nigel Goodwin]

Servos don't move anywhere near 360 degrees.

 

[Acetronics]

hi,

360° clockwise and 360° anti-clockwise are TWO turns ...

only special winch dedicated servos can do that : HS-785HB - Hitec RCD is an example

no hope with a classical servo !!!

Alain

 

[Transistorman]

Servos don't move anywhere near 360 degrees.

i use a continous move servo

 

[Transistorman]

hi,

360° clockwise and 360° anti-clockwise are TWO turns ...

only special winch dedicated servos can do that : HS-785HB - Hitec RCD is an example

no hope with a classical servo !!!

Alain

i think its right
if there was a tutorial for that it will be help me

 

[Nigel Goodwin]

i use a continous move servo

You don't really get continuous movement servos, you can modify them, but it's not a servo anymore, just a motor and gearbox.

 

[Transistorman]

[qoute]just to roll it 180 dgrs then come back to 180 dgrs again and loop it forever[/qoute]
as i say , please i really need it

 

[Nigel Goodwin]

A standard servo uses a potentiometer for it's positioning, so has a theoretical absolute maximum travel of 270 degrees. But in practice it's a LOT less than that - they are designed for a specific job, and don't require massive movement.

 

[Pommie]

I posted a but it should convert easily.

Mike.

 

[Transistorman]

I posted a but it should convert easily.

Mike.

i never convert a 18 series program to 16 series program
and , i didnt have any 18 series PIC

edit : my question is

just to roll it 180 dgrs then come back to 180 dgrs again and loop it forever

please help me !

 

[colin55]

Do you want the servo to turn according to the position of a pot?

 

[Transistorman]

Do you want the servo to turn according to the position of a pot?

no , just 180 degress

 

[colin55]

How may degrees does the servo turn?

 

[Nigel Goodwin]

You first need to aquire a servo that will do what you want, most probably won't move that far.

 

[Transistorman]

180 degress
my servo is S04NF

 

[Nigel Goodwin]

180 degress

So have you bought a servo that will move that far?.

 

[Pommie]

Don't all servos move nearly 270° in each direction which is more than 180°? Is the OP saying he wants it to go from -90° to +90° then to -90° and repeat?

Edit, I don't have time now but tomorrow I'll post BoostC code to control a pot on a 16 series chip. Do you have a 16F88?

Mike.

 

[Transistorman]

Don't all servos move nearly 270° in each direction which is more than 180°? Is the OP saying he wants it to go from -90° to +90° then to -90° and repeat?

Edit, I don't have time now but tomorrow I'll post BoostC code to control a pot on a 16 series chip. Do you have a 16F88?

Mike.

no i dont , but i have 16F886

 

[allbits]

From you older posts, I understand, you have a continuous rotation servo. And that you need to rotate the shaft 180 degrees to the right and to the left, in a loop.
try this -
1) Write a subroutine to turn the motor to the left - say, goLeft();
2) Write another to turn to right - say goRight();
Find the time for the shaft to reach your 180 degrees. Write a subroutine for the time delay

call goLEft and goRight with the delay subroutine in between, and put the entire thing in a loop.

This is, assuming you know how to turn your motor to the left and to the right. If you have variations in the load at shaft, the time will change. If the positioning is critical, put a sensor at the 180 degree point. Then wait for the shaft to reach that point before you call either of the goLeft or goRight subroutines.

 

[Nigel Goodwin]

Don't all servos move nearly 270° in each direction which is more than 180°?

No, servos only have a fairly limited movement - which the specs don't seem to mention?.

It certainly couldn't be 270 degrees in each direction, that would require 540 degrees total movement, and the pot can only move a possible maximum of 270 degrees.