Mitsubishi Electric MELSEC-L LD75P User Manual page 569

• The following drawing shows an operation when data is transferred to the servo amplifier.
ABRST
S+4 (Status)
Statuses of
D+0 (Complete device)
devices
BUSY signal
Statuses of
Positioning complete
the LD75
signal
Axis operation status
Servo ON
(SON)
ABS transfer
mode (ABSM)
ABS request (ABSR)
I/O signals
from/to servo
amplifier
ABS transmission
data ready (ABST)
Transmission (ABS) data
1.
The BUSY signal is turned ON and the axis operation status is set to "Analyzing" by the dedicated
instruction "ABRST". At this time, the signal is controlled to turn OFF the servo amplifier. The
servo is powered OFF in 60ms + scan time.
2.
When the servo is turned ON, the ABS transfer mode is simultaneously turned ON. After receiving
the ABS transfer mode, detecting the absolute position and calculating the absolute position, the
servo amplifier will turn ON the ABS transmission data ready (ABST) and answer back to LD75
notifying that the send data is ready.
3.
After recognizing that the ABS transmission data ready (ABST) turned ON, LD75 turns ON the ABS
request (ABSR).
4.
The servo amplifier outputs the ABS lower 2 bits and ABS transmission data ready (ABST) OFF by
the ABS request (ABSR).
5.
After recognizing that the ABS transmission data ready (ABST) turned OFF (the ABS2bit data is
output), LD75 reads the lower 2bits of ABS and turns OFF the ABS request (ABSR).
"ABRST " is executed continuously until "S+4" becomes 0.
Values other than 0 (the phase numbers of absolute position restoration) is
0
stored after the process starts.
ON for one scan
1.
ON
OFF
ON
OFF
2.
ON
Approx. 60ms + scan time
OFF
ON
OFF
3. 5.
ON
OFF
4. 6.
ON
OFF
Lower
2bit
CHAPTER 12 CONTROL SUB FUNCTIONS
Analyzing
7.
ABS transmitting
Checksum
higher 2bit
0
12
Standby
567