Output Ports For The Position Data From The Absolute Linear Encoder; Reading The Position Data From The Absolute Linear Encoder; Linear Encoder - YASKAWA SGD7S Product Manual

6.9.3 Output Ports for the Position Data from the Absolute

Linear Encoder

You can read the position data of the absolute linear encoder from the PAO, PBO, and PCO (Encoder
Divided Pulse Output) signals.
The output method and timing for the position data of the absolute linear encoder are different in each
case.
A conceptual diagram of the connections of the PAO, PBO, and PCO (Encoder Divided Pulse Output)
ports to the host controller is provided below.
Serial
data
ENC
Signal
First signal
PAO
During normal operation
First signal
PBO
During normal operation
PCO Always
The PAO (Encoder Divided Pulse Output) signal outputs the position data from the absolute lin-
ear encoder after the control power supply is turned ON. The SENS_ON (Turn ON Sensor)
command is used to output the position data from the absolute linear encoder.
The position data of the absolute linear encoder is the current stop position. The absolute linear
encoder outputs the upper 16-bit data (with sign) according to the specified protocol. The absolute
encoder outputs the lower 20-bit data as a pulse train. It then outputs pulses as an incremental linear
encoder (incremental operation status).
The host controller must have a reception circuit (e.g., UART) for the position data from the absolute
linear encoder. The pulse counter at the host controller will not count pulses when the upper 16-bit
data (with sign) (communications message) is input because only phase A is input.
The output circuits for the PAO, PBO, and PCO signals use line drivers. Refer to the following section
for details on line drivers.
4.5.4
I/O Circuits
6.9.4 Reading the Position Data from the Absolute Linear
Encoder
The SENS_ON (Turn ON Sensor) command is used to read the position data from the absolute
linear encoder.
The sequence for using the SENS_ON command to read the position data from the absolute linear
encoder of a Linear Servomotor is given below.
The upper 16-bit position data (with sign) are sent according to the transmission specifications.
The lower 20-bit data is output as a pulse train.

6.9.3 Output Ports for the Position Data from the Absolute Linear Encoder

SERVOPACK
CN2
Conversion of Dividing
serial data to
circuit
pulses
(Pn281)
Status
When Using an Absolute Linear Encoder
Upper 16-bit data (with sign)
Lower 20-bit data (pulse train)
Incremental pulses
Lower 20-bit data (pulse train)
Incremental pulses
Origin pulse
on page 4-39
Host controller
CN1
PAO
PBO
PCO
Signal Contents
6.9 Absolute Linear Encoders
6
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