Delta Tau Geo MACRO, Руководство пользователя и справочное руководство

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Geo MACRO Drive User and Reference Manual
Software Setup 43
SOFTWARE SETUP FOR GEO MACRO DRIVES
Introduction
Turbo PMAC2 controllers can command axes and I/O over the MACRO ring. Most commonly, this is
done with an Ultralite board-level Turbo PMAC2 controller that is installed as an expansion card in the
host computer, communicating to MACRO Stations, MACRO-based drives, and/or MACRO peripheral
devices over the MACRO ring. However, it is also possible for a UMAC Turbo with the ACC-5E
MACRO interface, to command devices over the MACRO ring.
It is advisable to the user to use the Turbo Setup program to set up his Geo MACRO application(MACRO
communications, feedback setup, commutation, and motor setup), or to use the MACRO Ring ASCII
setup tool which comes with the PEWIN32PRO2 and sets up the MACRO communications, and displays
to the user some useful information about his system. Sample screens and procedures for these programs
are shown in the following section
Establishing MACRO Communications with Turbo PMAC
Several variables must be set up properly for proper ring operation. Usually, this is done automatically
through use of the Turbo Setup program or with the new application tool PEWIN32PRO2 MACRO Ring
ASCII on a PC. The following instructions permit direct manual setting of these variables.
MACRO Ring Frequency Control Variables
The MACRO ring update frequency is the phase clock frequency of the ring master controller. If there is
more than one Turbo PMAC2 controller on the ring, only one of them can be the ring master controller
(others are masters, but not ring masters). Of course, if there is only one Turbo PMAC2 controller on the
ring, it will be the ring master controller. Determining which Turbo PMAC2 (technically, which
MACRO IC on a Turbo PMAC2) is ring master is explained below.
While the ring master has the capability to force the clock generation of other devices on the ring into
synchronization, it is strongly recommended that all devices on the ring, both other Turbo PMAC2
controllers, and any slave devices, be set up for the same phase clock frequency. Determining which IC
sets the phase clock frequency and the actual setting the phase clock frequency for a Turbo PMAC2
controller is explained above.
For a Turbo PMAC2 driving a MACRO ring, MACRO IC 0 should generate the phase clock signal. This
means that I19 should be set to 6807 (which it will be by default on virtually any Turbo PMAC2 capable
of driving a MACRO ring), and that I6800 and I6801 set the phase clock frequency.
I7: Phase Cycle Extension
On the Turbo PMAC2 board, it is possible to skip hardware phase clock cycles between executions of the
phase update software. A Turbo PMAC2 board will execute the phase update software – commutation
and/or current-loop closure – every (I7+1) hardware phase clock cycles. The default value for I7 is 0, so
normally Turbo PMAC2 executes the phase update software every hardware phase clock cycle.
If the Turbo PMAC2 board is closing the current loop for direct PWM control over the MACRO ring, it is
desirable to have two hardware ring update cycles (which occur at the hardware phase clock frequency)
per software phase update. This eliminates one ring cycle of delay in the current loop, which permits
slightly higher gains and performance. To do this, I7 would be set to 1, so the phase update software
would execute every second hardware phase clock cycle, and ring update cycle.
Normally it is desirable to close the current loop at an update rate of about 9 kHz (the default rate). If two
ring updates were desired per current loop update, the ring update frequency would need to be set to 18
kHz. This is possible if there are no more than 40 total active nodes on the ring. To implement this,
I6800 would be set to one-half of the default value, and I6801 to the default value of 0.