User's Manual

16-Axis MACRO CPU User Manual
12 Turbo PMAC2 Software Setup for MACRO Station
2. All MACRO stations on the ring should be running at the same ring (phase clock) rate. This is set on
the 16-Axis MACRO stations MI992 and MI997 and the Turbo Ultralite’s I6800, I6850, I6900, I6950
and I6801, I6851, I6901, I69551.
3. All MACRO stations on the ring should have their phase clock source synchronized to its own last
node packet on the MACRO ring. Normally, this is node 15, so bit 16-19 = $F of MI996 and Turbo’s
I6841, I6891, I6941, I6991. This means that the MACRO IC that is the source of the phase clock on
its station will have its phase clock resynchronized with its last received packet on the ring.
4. The synch node phase lock enable bit must not be set on the synchronizing master. Since it is the
source of the MACRO ring data rate, it does not make sense to synchronize to itself and it may cause
problems. This is bit 7=0 of Turbo’s I6840.
5. The synch node phase lock enable bit must be set on the separate Turbo PMAC non-synchronizing
masters and the MACRO slaves. It should be set only on the MACRO IC that is the source of the phase
clock and not on the other MACRO IC on the board. This is bit 7=1 and typically is I6690 of the Turbo
PMAC non-synchronizing masters and MI996 of MACRO IC 1 of the 16-Axis MACRO station.
6. The source of phase and servo clocks for the synchronizing master must be MACRO IC 0 and it must
be master number 0. I6841 = $0FCxxx and I6807=0, I6857=3, I6907=3, I6997=3. Because MACRO
ICs 1-3 cannot generate the servo clock, they report back a 1.
7. The source of phase and servo clocks for the non-synchronizing master must be the last MACRO IC
that is enabled as a Master. If this is MACRO IC 3, then I6807=1, I6857=3, I6907=3, I6997=0. This
allows all four MACRO ICs to receive their data before a phase interrupt occurs.
8. The source of phase and servo clocks for a slave must be the last MACRO IC that receives its data. For
the 16-Axis MACRO CPU, this most likely will be MACRO IC 1. The idea is to receive the command
data into both MACRO IC 0 and 1 and then resynch (reset) the phase clock and get the phase interrupt.
MI142 determines which MACRO IC is the source of the phase clock and the synch node phase lock
enable. When MI142=0, it is MACRO IC 1. If using only MACRO IC0, then set MI14=0.
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
should have two hardware ring update cycles (which occur at the hardware phase clock frequency) per
software phase update. This eliminates one software cycle of delay in the current loop, which permits
slightly higher gains and performance. To do this, set I7 to 1, so that the phase update software would
execute every second hardware phase clock cycle and ring update cycle.
Normally the current loop should be closed at an update rate of about 9 kHz (the default rate). If two ring
updates are wanted per current loop update, the ring update frequency must be set to 18 kHz. This is
possible if there are no more than 40 total active nodes on the ring. To implement this, set I6800 or I7000
to one-half of the default value (see below).
Note:
When making this adjustment, change the Turbo PMAC’s I6800/I7000 variable
first, then the MACRO Station’s MI992. Changing the MACRO Station’s MI992
alone, followed by an MSSAVE command and an MS$$$ command could cause
the Station’s watchdog timer to trip.