In NCQ & RCX Code, "Off" is the closest one gets to "locking" a motor. It will resist being turned, but in a crane application I can envision enough force to externally turn the shaft. You can prevet this from happening by including a worm gear in (...) (25 years ago, 27-Jan-00, to lugnet.robotics.rcx.nqc)
Thanx. That solved my problem. (...) including a (...) directions (...) drives. (...) used (...) where (...) (25 years ago, 27-Jan-00, to lugnet.robotics.rcx.nqc)