YASKAWA S-7 Series Command Manual page 112

3.2 Servo Commands
3.2.14 Zero Point Return Command (ZRET: 3Ah)
Command-specific Data
The following describes the data specific to the ZRET command.
MODE (Lower 1 byte)
bit7
HOME_DIR
• MODE.HOME_DIR (Zero point return direction)
Selects the zero point return direction.
MODE.HOME_DIR = 0:Positive direction
MODE.HOME_DIR = 1:Negative direction
• MODE.TYPE (Zero point return type)
Sets the zero point return type on selection of the type from the patterns below.
MODE.TYPE = 0:Latch signal
MODE.TYPE = 1:Deceleration limit switch + Latch signal
Operating Sequence
The following describes the zero point return operating sequence for each of the zero point
return modes.
 MODE = 0 (Latch Signal)
1.
The master station sends the ZRET command. It selects the latch signal with LT_SEL1
of SVCMD_CTRL and outputs the latch request by setting LT_REQ1 = 1.
2.
The slave station starts feeding in the direction specified by MODE.HOME_DIR at the
speed set for the Homing Approach Speed (common parameter 84).
3.
When the current position latch signal, specified by LT_SEL1 of SVCMD_CTRL, is input,
the slave station executes positioning through the movement of the Final Travel Dis-
tance for Homing (common parameter 86) at the Homing Creep Speed (common param-
eter 85). After the completion of positioning, the slave station sets the zero point of the
reference coordinate system.
3-46
bit6 bit5
Reserved Reserved
Speed
(2)
Approach speed
Position latch signal
bit4 bit3
Reserved
(3)
Creep
speed
bit2 bit1
TYPE
Final travel distance
for zero point return
Zero point
Time
bit0