Delta Tau Geo MACRO, User Manual And Reference Manual

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Geo MACRO Drive User and Reference Manual
Software Setup 47
been detected in this interval, Turbo PMAC will assume a major ring problem, and all motors will be shut
down. Turbo PMAC will set the global status bit “Ring Error” (bit 4 of X:$000006) as an indication of
this error.
Turbo PMAC looks for receipt of sync node packets and ring communications errors once per real-time
interrupt – every (I8 + 1) servo cycles). The time interval set by I80 must be large enough that I82 real-
time interrupts in PMAC can execute within the time interval, or false ring errors will be detected.
Remember that long motion program calculations can cause skips in the real-time interrupt. Typically
values of I80 setting a time interval of about 20 milliseconds are used. I80 can be set according to the
formula:
I80 = Desired cycle time (msec) * Servo update frequency (kHz)
For example, with the default servo update frequency of 2.26 kHz, to get a ring check cycle interval of 20
msec, I80 would be set to 20 * 2.26
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45.
MACRO Node Addresses
The MACRO ring operates by copying registers at high speed across the ring. Therefore, each Turbo
PMAC2 master controller on the ring communicates with its slave stations by reading from and writing to
registers in its own address space. MACRO hardware handles the data transfers across the ring automatically.
Starting in Turbo firmware version 1.936, the base addresses of the up to 4 MACRO ICs must be
specified in I20 – I23, for MACRO IC 0 – 3 respectively. Before this, the base addresses were fixed at
$078400, $079400, $07A400, and $07B400, respectively. Only UMAC Turbo systems can support any
other configuration, and only rarely will another configuration be used.
The following table gives the addresses of the MACRO ring registers for Turbo PMAC2 controllers.
Note:
It is possible, although unlikely, to have other addresses in a UMAC Turbo system.
In these systems, the fourth digit does not have to be 4; it can also take the values
5, 6, and 7.