Absolute Position Data Transfer Protocol - Mitsubishi Electric MR-J5 Series User Manual

The servo motor shaft may operate unexpectedly if the positioning operation is performed without homing. Perform homing
before starting.

Absolute position data transfer protocol

The following shows the data transfer procedure. After switching on ABSM, turn on SON. When ABSM is off, turning on SON
does not switch on the base circuit.
Data transfer procedure
Each time SON is turned on, such as when the power is switched on, the current position data in the servo amplifier is read to
the programmable controllers.
Time-out monitoring is performed on the programmable controllers side.
Servo amplifier
DIO assignment change
Transmission data set
Transmission data set
DIO assignment change
7 ABSOLUTE POSITION DETECTION SYSTEM
200
7.3 Absolute position detection system by DIO [A]
SON (Servo-on) on
ABSM (ABS transfer mode) on
ABST (ABS transmission data ready) on
ABSR (ABS request) on
ABST (ABS transmission data ready) off
ABSR (ABS request) off
ABST (ABS transmission data ready) on
ABSR (ABS request) on
ABST (ABS transmission data ready) off
ABSR (ABS request) off
ABST (ABS transmission data ready) on
ABSM (ABS transfer mode) off
ABST (ABS transmission data ready) off
Programmable controller
Monitoring timer
Reading 2 bits
Shift and add
Monitoring timer
Reading 2 bits
Shift and add
Current position set
Sum check
Each time SON is turned on,
ABSM is turned on and data
transfer is ready.
<Current position data>
The data is read in units of
two bits, and the read data is
shifted by two bits to the right
and written as the lowest bits.
This step is repeated until
32-bit data is configured.
<Sum check data>
The data is read in units of
two bits, and the read data is
shifted by two bits to the right
and written as the lowest bits.
This step is repeated until
6-bit data is configured.
A sum check is executed for
the received 32-bit data.
After the programmable
controller makes sure that
there are no errors in the
transfer data, the current
position is set.
16 times
3 times