Reference Manual

Turbo PMAC/PMAC2 Software Reference
Turbo PMAC Global I-Variables 75
When a ring fault is detected, Turbo PMAC sets bit 4 of global status word X:$000006 to 1. It disables
all motors using the MACRO ring, and attempts to notify all of its MACRO slave stations that a ring fault
has occurred.
Turbo PMAC performs this check each real-time interrupt (every I8+1 servo cycles), so it will perform
I80 / (I8 + 1) checks during the check period. This value must be greater than I82, or ring failures will be
detected because not enough checks were done to detect the required number of sync packets received.
This function is controlled by I1001 on non-Turbo PMACs.
I81 MACRO Maximum Ring Error Count
Range: 0 .. 255
Units: Detected ring errors
Default: 2
I81 sets the maximum number of MACRO ring communications errors that can be detected in one ring
check period before a MACRO communications fault is declared. The ring check period is set at I80
servo cycles; if I80 is 0, this checking is not performed.
There are four types of ring communications errors that can be detected: byte violation errors, packet
parity errors, packet overflow errors, and packet underflow errors. If any one of these is detected during a
check, this counts as a ring error towards the I81 counts.
Turbo PMAC performs the check every real-time interrupt (every I8+1 servo cycles), so it will perform
I80 / (I8 + 1) checks during the check period. If I81 or more ring errors are detected during this period, a
ring fault is declared, and the ring is shut down. Regardless of the setting of I81, if a ring error is detected
on every check during the period, a ring fault is declared.
This function is controlled by I1004 on non-Turbo PMACs.
I82 MACRO Minimum Sync Packet Count
Range: 0 .. 255
Units: Detected sync packets
Default: 2
I82 sets the minimum number of MACRO sync packets that must be received in one ring check period for
Turbo PMAC to conclude that the ring is operating properly. The ring check period is set at I80 servo
cycles; if I80 is 0, this checking is not performed.
The number of the sync packet is determined by bits 16 – 19 of I6841. Usually Packet 15 is used as the
sync packet, and its transmission around the ring is enabled by setting bit 15 of I6841 to 1, activating
Node 15. If the sync packet is defined as a packet that is not regularly transmitted around the ring, this
check will shut down the ring immediately.
If fewer than I82 sync packets are detected during any ring check period of I80 servo cycles, Turbo
PMAC will shut down operation of the ring, declaring a ring fault. Turbo PMAC performs the check
during the real-time interrupt (every I8+1 servo cycles), so it will perform I80 / (I8 + 1) checks during the
check period. If I82 is set to a value greater than I80 / (I8 +1), Turbo PMAC will find a ring fault
immediately.
This function is controlled by I1005 on non-Turbo PMACs.
I83 MACRO Parallel Ring Enable Mask
Range: 0 – 15
Units: none
Default: 0