Reference Guide

PMAC Quick Reference Guide
Introduction 1
INTRODUCTION
Description of PMAC
PMAC, pronounced Pe’-MAC, stands for Programmable Multi-Axis Controller. It is a family of high-
performance servo motion controllers capable of commanding up to eight axes of motion simultaneously
with a high level of sophistication.
There are five hardware versions of PMAC: the PMAC PC, the PMAC Lite, the PMAC VME, the PMAC
STD and the PMAC Mini. These cards differ from each other in their form factor, the nature of the bus
interface, and in the availability of certain I/O ports.
• Motorola’s Digital Signal Processor (DSP) DSP56k is the CPU for PMAC and it handles all the
calculations for all eight axes.
• The registers in PMAC’s DSPGATE Gate-Array ICs are mapped into the memory space of PMAC’s
processor. Each DSPGATE contains four consecutively numbered channels; there may be up to four
DSPGATEs in a PMAC system, for up to 16 channels.
• There are two types of servo DSPGATE Gate-Array ICs: The PMAC type that allows only the
control of analog amplifiers with ±10V command signals and the PMAC2 type that is capable also of
digital direct PWM or stepper command signals.
• Each PMAC channel provided by a PMAC DSPGATE has one DAC output, one encoder input and
four dedicated flag inputs: two end-of-travel limits, one home input and one amplifier fault input.
• Any PMAC can control up to eight motors or axis as long as enough channels are provided. Every
PMAC contains one DSPGATE, which has channels 1 through 4 (PMAC Mini has only two
channels). If Option 1 is ordered (not available on PMAC Lite or PMAC Mini), a second DSPGATE
is provided, which has channels 5 through 8. If Acc-24 is ordered (not available on PMAC STD), a
third DSPGATE is provided which has channels 9 through 12. If Acc-24 Option 1 is ordered as well
(not available on PMAC STD), a fourth DSPGATE is provided, which has channels 13 through 16.
• PMAC has its own memory and microprocessor. Therefore, any version of PMAC may run as a
standalone controller or a host computer may command it either over a serial port or a bus port.