USA57 Revision
1.2
101
Appendix I
Encoders and Step & DIR Pulse Input
The Accuriss has dual encoder inputs. Any quadrature encoder with A, B and (optional) index
output is acceptable. In addition, step and direction style position counting is also supported on
the secondary encoder.
Read-Only Mode
In this, the simplest mode, the encoder values are simply read back.
The command
/1?8
reads the primary encoder on the 5-pin connector, and
/1?10
reads back
the secondary encoder on the 8-pin connector. The primary encoder is always in quadrature
encoder mode and expects quadrature pulses on the A & B lines. The secondary encoder can
be placed in quadrature encoder or in step and direction counting mode, depending on whether
or not
/1n32R
mode is enabled.
The
/1?8
command
reads back the primary encoder when in
aM1
mode.
Encoder/Step and Direction Following Mode
In this mode, the motor takes the count from the secondary encoder and uses this count as a
commanded position. The count can come in from another A, B quadrature style encoder, or
from step and direction pulses.
1. Select A & B mode or step and direction mode using
/1n32R
etc.
2. Turn on “Motor Slave to Encoder2” by issuing
/1n64R
.
Examples: A
/1n96R
(96=32+64) command enables step and direction mode and slaves the
motor to it. A
/1n64R
command
enables the encoder mode and slaves the motor to it.
The input step count (readable by
/1?10
) is related to the motor position by the following
relationship:
Step motor position = (“am” multiplier / 256) x (step and direction count or encoder count).
Counts are in the number of microsteps set by the “
j”
command.
Main Axis Encoder Feedback Mode
The main axis can use the primary encoder for feedback and the secondary encoder for
“command.” Please see Appendix E
Electrical
Please see the appropriate product wiring diagram for wiring details.
The encoder(s) must draw a total current of <100mA from the 5V pin.