User's Manual

PMAC User Manual
Input/Output: Connecting PMAC to the Machine 49
PMAC is shipped standard with a ULN2803A sinking (open-collector) output IC for the eight outputs.
These outputs can sink up to 100mA, but must have a pull-up resistor to go high.
CAUTION:
Do not connect these outputs directly to the supply voltage, or damage to the
PMAC will result from excessive current draw.
Provide a high-side voltage (+5 to +24V) into Pin 33 of the JOPTO connector and allow this to pull up
the outputs by connecting pins 1 and 2 of Jumper E1. Jumper E2 must also connect pins 1 and 2 for a
ULN2803A sinking output.
Option for Sourcing Outputs
CAUTION:
Having Jumpers E1 and E2 set wrong can damage the IC.
It is possible for these outputs to be sourcing drivers by substituting a UDN2981A IC for the ULN2803A.
This IC (U3 on the PMAC PC, U26 on the PMAC Lite, U33 on the PMAC VME) is socketed, and so
may be replaced easily. For this driver, use pull-down resistors. With a UDN2981A driver IC, Jumper
E1 must connect pins 2 and 3, and Jumper E2 must connect pins 2 and 3.
Input Source/Sink Control
Jumper E7 controls the configuration of the eight inputs. If it connects pins 1 and 2 (the default setting),
the inputs are biased to +5V for the OFF state, and they must be pulled low for the ON state. If E7
connects pins 2 and 3, the inputs are biased to ground for the OFF state, and must be pulled high for the
ON state. In either case, a high voltage is interpreted as a 0 by the PMAC software, and a low voltage is
interpreted as a 1.
Thumbwheel Multiplexer Port I/O (JTHW Port)
Multiplexed Uses
The Thumbwheel Multiplexer Port, or Multiplexer Port, on the JTHW (J3) connector has eight input lines
and eight output lines. The output lines can be used to multiplex large numbers of inputs and outputs on
the port, and Delta Tau provides accessory boards and software structures (special M-variable definitions)
to capitalize on this feature. Up to 32 of the multiplexed I/O boards may be daisy-chained on the port, in
any combination.
Port Accessories
The Acc-18 Thumbwheel Multiplexer board provides up to 16 BCD thumbwheel digits or 64 discrete
TTL inputs per board. The TWD and TWB forms of M-variables are used for this board.
The Acc-34, -34A, and -34B Serial I/O Multiplexer boards provides 64 I/O point per board, optically
isolated from PMAC. The TWS form of M-variables is used for these boards.
The Acc-8D Option 7 Resolver-to-Digital Converter board provides up to four resolver channels whose
absolute positions can be read through the thumbwheel port. The TWR form of M-variables is used for
this board.
The Acc-8D Option 9 Yaskawa
™
Absolute Encoder Interface board can connect to up to four of these
encoders. The absolute position is read serially through the multiplexer port on power up.