OpenServo.com

florianfreitag · Joined: 07 Apr 2010 Posts: 4 Location: Germany, Karlsruhe

Hello,

I want to use Hitec HS-645MG servos with the OpenServo. But when I compile the firmware its not working. Which registers and values I have to use for this servo?
Because there is no default HARDWARE_TYPE for this servo and the HS-475HB values are not working correctly.

So I need following informations, but where to find:

jharvey · Posted: Thu Jun 17, 2010 9:27 am Post subject:

Perhaps other can help with the information you have posted. I would need more information. What's the platform you are compiling with, Linux, windows, other? Did you check out a CVS copy of the code? If so did that compile with out changes? If not what were the error messages? Have you made changes to the code since it was checked out?

rotdrop · Joined: 15 Dec 2009 Posts: 16 Location: Germany, Ruhrpott

I have done some very quick testing with a Hitec 645MG, and for me the values for used for the 475HB in the config.h file seem to work as well for the 645MG, I have only adjusted the minium/maximum seek positions.

So what do you mean by "not working correctly"?

Best regards,

Claus

florianfreitag · Joined: 07 Apr 2010 Posts: 4 Location: Germany, Karlsruhe

Thanks for your quick answers!

My platform is Windows XP with AVR Studio and I've checked out the latest CVS snapshot. There are no other modifications on the code. There are no compiler errors and no warnings. The error is that the servo goes direct to his min or max position or it does nothing.
I think these values are not correct. @rotdrop What are your values for these variables?

Best regards!

jharvey · Posted: Fri Jun 18, 2010 9:53 am Post subject:

Max values often means the motor leads are backwards. The software commands CW, and the motor goes CCW, which makes the error signal increase, so it commands faster CW, but it goes faster CCW, until it hits the limit.

Doing nothing can mean a variety of things. Some common ones include a need to set PID setting, or turning on and off the PWM. Compiling in the PID settings is handy, however you can change them on the fly via I2C. Is this servo being commanded via I2C?

rotdrop · Joined: 15 Dec 2009 Posts: 16 Location: Germany, Ruhrpott

@florian: After porting the OSIF test application from Qt3 to Qt4 I can confirm that my instance of the OS controller installed in my version of a Hitec 645MG servo works with just the same PID values as the Hitec 475. Didn't test it in a real application, though.

Cheers,

Claus