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Operation Theorem
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4.3 The Limit Switch Interface and I/O Status
In this section, the following I/O signals’ operations are described.
Ÿ
±
SD: Ramping Down sensor
Ÿ
±
EL: End-limit sensor
Ÿ
ORG: Origin position
Ÿ
SVON and RDY
I /O status readback
In any operation mode, if an
±
EL signal is active during moving condition,
it will cause PCI-8132 to stop output pulses automatically. If an SD signal
is active during moving condition, it will cause PCI-8132 to decelerate.
4.3.1 SD
The ramping-down signals are used to slow-down the control output
signals (OUT and DIR) when it is active. The signals are very useful to
protect the mechanism moving under high speed toward the mechanism
limit. PSD indicates ramping-sown signal in plus (+) direction and MSD
indicates ramping-down signal in minus (-) direction.
During varied speed operation in the home return mode or continuous
operation mode, the ramping-down signal in the moving direction lets the
output control signals (OUT and DIR) ramp down to the pre-setting
starting velocity.
The ramping-down function can be enable or disable by software function:
_8132_set_sd_logic() . The input logic polarity, level operation mode, or
latched input mode can also be set by this function. The signals status
can be monitored by
_8132_
get_io_status() .
4.3.2 EL
The end-limit signals are used to stop the control output signals (OUT and
DIR) when the end-limit is active. PEL signal indicates end-limit in
positive (plus) direction. MEL signal indicates end-limit in negative
(minus) direction. When the output pulse signals (OUT and DIR) are
toward positive direction, the pulse train will be immediately stopped when
the PEL signal is inserted, while the MEL signal is meaningless in this
case, and vise versa. When the PEL is inserted and the output pulse is
fully stop, only the negative (minus) direction output pulse can be
generated for moving the motor to negative (minus) direction.