ADLINK Technology cPCI-8168, User Manual

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70 Operation Theory
cally installed and the servo signal is turned off, the axis will be in
uncontrolled state and can fall down to the ground. Some situa-
tions, like servo alarm and emergeny signal ON, can have the
same negative result.
4.3.7 Servo Ready Signal
The servo ready signal is a general digital input on the motion con-
troller and has no relative purpose to the motion controller. Users
can connect this signal to the motor driver’s RDY signal to check if
the motor driver is in a ready state. This signal can let users know
if the motor driver’s power has been inputed or not, or it can be
connected as a general input for another purpose. This singal has
no effect on motion control.
4.3.8 Servo alarm reset switch
The servo driver will raise an alarm signal if there is something
wrong inside the servo driver. Some alarm situations are the servo
motor is over current, over speed, over loading and so on. Power
reset can clear the alarm status but users usually don’t want to
power off the servo motor while in operation. There is one servo
driver pin used to reset the alarm status. cPCI-8168 provides one
general output pin for each axis to be used to reset servo alarm
status.
4.4 Mechanical switch interface
We provide some dedicated input pins for mechanical switches
like original switch (ORG), plus and minus end-limit switch (?EL),
slow down switch (SD), positioning start switch (PCS), counter
latch switch (LTC), emergency stop input (EMG) and counter
clear switch (CLR). These switches’ response time is very fast,
only a few ASIC clock times. There is no real-time problem when
using these signals. All functions are done by motion ASIC. The
software does not need to do anything other than wait for the
results.