User's Manual

Turbo PMAC PCI HRM
Machine Connections 33
Example:
Amplifier Enable Signal (AENAx/DIRn)
Most amplifiers have an enable/disable input that permits complete shutdown of the amplifier regardless of
the voltage of the command signal. PMAC's AENA line is meant for this purpose. If not using a direction
and magnitude amplifier or voltage-to-frequency converter, use this pin to enable and disable the amplifier
(wired to the enable line). AENA1/DIR1 is pin 47. This signal is an open-collector output with a 3.3 kΩ
pull-up resistor to +V, which is a voltage selected by jumper E100. The pull-up resistor packs are RP43 for
channels 1-4 and RP-56 for motors 5-8. For early tests, this amplifier signal should be under manual control.
This signal could be either sinking or sourcing as determined by chips U37 and U53 (see jumpers E100-
E102 and E114-E115). For 24V, operation E100 must connect pins 2-3 and a separate power supply must
be brought on pins 9-7 of the J9 JEQU connector. The polarity of the signal is controlled by jumpers E17A
to E17H. The default is low-true (conducting) enable. The amplifier enable signal could also be manually
controlled setting Ix00=0 and using the suggested definition of the Mx14 variable.
Amplifier Fault Signal (FAULTn)
This input can take a signal from the amplifier so PMAC knows when the amplifier is having problems, and
can shut down action. The polarity is programmable with I-variable Ix25 (I125 for motor #1) and the return
signal is analog ground (AGND). FAULT1 is pin 49. With the default setup, this signal must actively be
pulled low for a fault condition. In this setup, if nothing is wired into this input, PMAC will consider the
motor not to be in a fault condition. The amplifier fault signal can be monitored using the properly defined
Mx23 variable.