Reference Manual

Turbo PMAC/PMAC2 Software Reference
Turbo PMAC Global I-Variables 215
I7m01 Servo IC m Phase Clock Frequency Control
Range: 0 - 15
Units: Phase Clock Frequency = MaxPhase Frequency / (I7m01+1)
Default: 0
Phase Clock Frequency = 9.0346 kHz / 1 = 9.0346 kHz
(with default value of I7m00)
I7m01, in conjunction with I7m00, determines the frequency of the Phase clock generated inside each
PMAC2-style Servo IC m. However, only the Servo IC told to use and output its own Phase clock with
I7m07, typically Servo IC 0 uses the Phase clock signal it generates. This means that I7001, in
conjunction with I7000, typically controls the Phase clock frequency for the entire Turbo PMAC2 system.
(For Turbo PMAC2 Ultralite boards, I6801 and I6800 control this.) Each cycle of the Phase clock, motor
phase commutation and digital current-loop algorithms are performed for specified motors.
Specifically, I7m01 controls how many times the Phase clock frequency is divided down from the
maximum phase clock, whose frequency is set by I7m00. The Phase clock frequency is equal to the
maximum phase clock frequency divided by (I7m01+1). I7m01 has a range of 0 to 15, so the frequency
division can be by a factor of 1 to 16. The equation for I7m01 is:
1
)kHz(PhaseFreq
)kHz(eqMaxPhaseFr
01m7I 
The ratio of MaxPhase Freq. to Phase Clock Freq. must be an integer.
Note:
If the phase clock frequency is set too high, lower priority tasks such as
communications can be starved for time. If the background tasks are completely
starved, the watchdog timer will trip, shutting down the board. If a normal reset of
the board does not re-establish a state where the watchdog timer has not tripped
and communications works well, it will be necessary to re-initialize the board by
powering up with the E3 re-initialization jumper on. This restores default settings,
so communication is possible, and I6000 and I6001 can be set to supportable
values.
For accessory boards in which alternate addressing of the Servo IC is used (labeled Servo IC m*), this
function is controlled by I7m51, not I7m01.
Example:
With a 20 kHz MaxPhase Clock frequency established by I7000, and a desired 6.67 kHz PHASE clock
frequency, the ratio between MaxPhase and Phase is 3:
I7001 = (20 / 6.67) - 1 = 3 -1 = 2
See Also: I19, I7m00, I7m02, I7m07, I6800, I6801, I6802, I6807
I7m02 Servo IC m Servo Clock Frequency Control
Range: 0 - 15
Units: Servo Clock Frequency = Phase Clock Frequency / (I7m02+1)
Default: 3
Servo Clock Frequency = 9.0346 kHz / (3+1) = 2.2587 kHz
(with default values of I7m00 and I7m01)
I7m02, in conjunction with I7m01 and I7m00, determines the frequency of the Servo clock generated
inside each PMAC2-style Servo IC. However, only the Servo IC told to use and output its own Servo
clock with I7m07, typically Servo IC 0, uses the Servo clock signal it generates.