YASKAWA SGD7S Product Manual page 418

13.2 Communications Methods
13.2.1 I/O Communications
 Home Flag
This bit is used to monitor the origin signal input to the SERVOPACK. This bit is set to 1 when
the current position is any position other than the origin. This bit is cleared to 0 when the cur-
rent position is the origin.
 Valid Data
This bit is set to 1 after the Valid Data bit is set to 1 in a command message from the master
device and the SERVOPACK has verified that the data in the command message from the mas-
ter device was received normally. If the Valid Data bit in the command message is set to 1, the
SERVOPACK will check the command data and if no problems are found, the Valid Data bit in
the response message will be set to 1. If there is an error in the command data, the Command
Error Flag will be set to 1 and the Valid Data bit will also be set to 1.
 Executing Block Number
This field contains the command block number (0 to 255) that is currently being executed. The
Executing Block Number Field is cleared to 0 when the block commands have been completed
or when a block error occurs (as shown by the Block Fault bit).
 Enable State
This bit is set to 1 when the servo is ON. If the servo is OFF in the SERVOPACK, the SERVO-
PACK will ignore the Start Trajectory bit even if it is set to 1 in a command message. Make sure
that this bit is set to 1 before setting the Start Trajectory bit.
 Servo Ready
This bit is set to 1 when the SERVOPACK is ready and the servo can be turned ON.
 CW Hardware Limit
This bit monitors the CW Drive Prohibit Input signal (the clockwise limit signal, as viewed from
the load end of the motor) that is connected to the SERVOPACK. It is set to 1 when the CW
Drive Prohibit Input signal is active.
 CCW Hardware Limit
This bit monitors the CCW-OT (CCW Drive Prohibit Input) signal (the counterclockwise limit sig-
nal, as viewed from the load end of the motor) that is connected to the SERVOPACK. It is set to
1 when the CCW-OT (CCW Drive Prohibit Input) signal is active.
 Positive Software Limit
This bit changes to 1 if the forward software limit is exceeded. The forward software limit is set
in PnB16 (Forward Software Limit).
 Negative Software Limit
This bit changes to 1 if the reverse software limit is exceeded. The reverse software limit is set
in PnB17 (Reverse Software Limit).
 Trajectory Start Echo
This bit is set to 1 if a command message is normally received from the master device with the
Start Trajectory bit set to 1. By checking this bit, the master device can check whether the
SERVOPACK received the Start Trajectory bit status normally.
 Block Fault
This bit changes to 1 if an error occurs during a block operation. If an error occurs, the block
operation will be stopped.
13-10