Bi-directional pass-point system for controlling the operation of movable barriers

A movable barrier operator comprising:

• a motor;
• a transmission connected to the motor to be driven thereby and for connection to the movable barrier to be moved;
• a pass-point assembly for detecting barrier displacements with respect to an intermediate reference point;
• and
• a controller for controlling such displacements within a predetermined range of motion;
• and
• a routine for automatically determining open and close limits of the movable barrier relative to the intermediate reference point;
• wherein in response to an open command, the routine causes the barrier to move in a first direction toward the intermediate reference point, measures the distance traveled to the reference point, and stores the complement of the distance traveled in the first direction as the close limit;
• and
• wherein in response to a close command, the routine causes the barrier to move in a second direction toward the intermediate reference point, measures the distance traveled to the reference point, and stores the complement of the distance traveled in the second direction as the open limit.

A method for automatically learning the open and close limits of travel comprising the steps of:

• receiving a command to cause the movable barrier to move in a first direction to a first position;
• moving the barrier in the first direction toward an intermediate reference point;
• measuring the distance traveled to the reference point;
• storing the complement of the distance traveled in the first direction as a first limit;
• receiving a command to cause the movable barrier to move in a second direction to a second position;
• moving the barrier in the second direction toward the intermediate reference point;
• measuring the distance traveled to the reference point;
• and
• storing the complement of the distance traveled in the second direction as a second limit.