User's Manual
Turbo PMAC User Manual
Basic Motor Setup 79
PMAC2-Style Servo IC Command Output Addresses (Y-registers)
IC# - Chan# 0 - 1 0 - 2 0 - 3 0 - 4 1 - 1 1 - 2 1 - 3 1 - 4
Ixx02
$078002 $07800A $078012 $07801A $078102 $07810A $078112 $07811A
IC# - Chan# 2 - 1 2 - 2 2 - 3 2 - 4 3 - 1 3 - 2 3 - 3 3 - 4
Ixx02
$078202 $07820A $078212 $07821A $078302 $07830A $078312 $07831A
IC# - Chan# 4 - 1 4 - 2 4 - 3 4 - 4 5 - 1 5 - 2 5 - 3 5 - 4
Ixx02
$079202 $07920A $079212 $07921A $079302 $07930A $079312 $07931A
IC# - Chan# 6 - 1 6 - 2 6 - 3 6 - 4 7 - 1 7 - 2 7 - 3 7 - 4
Ixx02
$07A202 $07A20A $07A212 $07A21A $07A302 $07A30A $07A312 $07A31A
IC# - Chan# 8 - 1 8 - 2 8 - 3 8 - 4 9 - 1 9 - 2 9 - 3 9 - 4
Ixx02
$07B202 $07B20A $07B212 $07B21A $07B302 $07B30A $07B312 $07B31A
Servo ICs 0 and 1 are on the Turbo PMAC2 itself or on Acc-2E 3U-format stack boards.
Servo ICs 2 – 9 are on Acc-24x2 or Acc-51E boards.
Channels 1 – 4 on odd-numbered Servo ICs are Channels 5 – 8 on the dual-IC boards.
When the Turbo PMAC is operating Motor xx in velocity mode or torque mode commanded over a
MACRO ring, Ixx02 will contain the address of a MACRO output register for one of the MACRO nodes.
When using the Type 1 MACRO protocol commonly found on multi-axis MACRO components such as
the Delta Tau MACRO Station, the following Ixx02 values should be used. Typically, these will be the
default values on a Turbo PMAC2 Ultralite.
MACRO Node Command Output Addresses (Y-registers)
IC# - Node# 0 - 0 0 - 1 0 - 4 0 - 5 0 - 8 0 - 9 0 - 12 0 - 13
Ixx02
$078420 $078424 $078428 $07842C $078430 $078434 $078438 $07843C
IC# - Node# 1 - 0 1 - 1 1 - 4 1 - 5 1 - 8 1 - 9 1 - 12 1 - 13
Ixx02
$079420 $079424 $079428 $07942C $079430 $079434 $079438 $07943C
IC# - Node# 2 - 0 2 - 1 2 - 4 2 - 5 2 - 8 2 - 9 2 - 12 2 - 13
Ixx02
$07A420 $07A424 $07A428 $07A42C $07A430 $07A434 $07A438 $07A43C
IC# - Node# 3 - 0 3 - 1 3 - 4 3 - 5 3 - 8 3 - 9 3 - 12 3 - 13
Ixx02
$07B420 $07B424 $07B428 $07B42C $07B430 $07B434 $07B438 $07B43C
If using the older Type 0 MACRO protocol, add 1 to the value shown in the above table (e.g. $078420
becomes $078421).
Setting Up Turbo PMAC2 for Pulse-and-Direction Control
A Turbo PMAC with PMAC2-style Servo ICs is capable of commanding stepper-motor drives that
require pulse-and-direction format input, or “stepper-replacement” servo drives that require this format.
Turbo PMAC can command these drives either in open-loop fashion, in which case it internally routes the
pulse train into its own encoder counters to create a pseudo-closed loop, or in closed-loop fashion, in
which case an external feedback device is wired to the Turbo PMAC to create a true feedback loop.
A PMAC2-style Servo IC creates its pulse-and-direction output signal with an on-board fully digital
pulse-frequency-modulation (PFM) circuit. This circuit repeatedly adds the latest command frequency
value into an accumulator at a programmable rate of up to 40 MHz. When the accumulator overflows, an
output pulse is generated with a positive direction signal; when the accumulator underflows, an output
pulse is generated with a negative direction signal. This creates a pulse train whose frequency is directly
proportional to the command value, with virtually no harmonic distortion, and none of the offset problems
that affect analog pulse generation schemes.