Mitsubishi Electric MR-J4, Instruction Manual

Page: 513 / 794

12. ABSOLUTE POSITION DETECTION SYSTEM
12 - 26
12.8 Communication-based absolute position transfer system
12.8.1 Serial communication command
The following commands are available for reading absolute position data using the serial communication
function. When reading data, take care to specify the correct station number of the servo amplifier from
where the data will be read.
When the master station sends the data No. to the slave station (servo amplifier), the slave station returns
the data value to the master station.
(1) Transmission
Transmit command [0] [2] and data No. [9] [1].
(2) Reply
The absolute position data in the command pulse unit is returned in hexadecimal.
Data 32-bit length (hexadecimal representation)
12.8.2 Absolute position data transfer protocol
(1) Data transfer procedure
Every time SON turns on at power-on or like, the controller must read the current position data in the
servo amplifier. Not performing this operation will cause a position shift.
Time-out monitoring should be performed by the controller.
Servo amplifier
Controller
Watch dog timer
Absolute position
data acquisition
SON on
RD on
Absolute position data
command transmission
Command [0][2] + data No.[9][1]
Absolute position data return
Position command start
Current position
acquisition
Current value
change