User's Manual

PMAC2 User Manual
Using PMAC2 with MACRO Interface 71
When commutating across the MACRO ring with Type 1 protocol, the commutation position feedback
appears in the 24-bit register for the node, with a count appearing in Bit 5, having a value of 32.
Therefore it appears to PMAC2 to be 32 times bigger than it really is. The commutation cycle size is
specified on PMAC2 as the ratio Ix71/Ix70. For a motor commutated across MACRO with Type 1
protocol, the value of these variables should produce a ratio 32 times bigger than the number of counts in
the commutation cycle. For example, for a two-pole motor (one commutation cycle per revolution) with
4096 counts per revolution, Ix70 should be set to 1 and Ix71 should be set to 4096 * 32 = 131,072.
Current Loop Feedback Address: Ix82
If PMAC2 is closing the current loop for a motor, Ix82 must contain the address of the current feedback
registers for that motor. This must be a Y-register, which means for MACRO, only nodes 0, 1, 4, 5, 8, 9,
12, and 13 can be used. When MACRO is used for this motor, the current feedback appears in two of the
real-time registers for the node; Ix82 specifies the higher address. The values of Ix82 to be used for each
MACRO node in either Type 0 or Type 1 protocol are:
Node Address Node Address
Node 0: $C0A2 Node 8: $C0B2
Node 1: $C0A6 Node 9: $C0B6
Node 4: $C0AA Node 12: $C0BA
Node 5: $C0AE Node 13: $C0BE