ElmoMC SimplIQ Software Manual - Manual (Page 156)

SimplIQ Software Manual The Position Reference Generator
MAN-SIMSW (Ver. 1.4)
11-15
11.1.6.2 Motion Management
In PVT mode, the drive manages a “read pointer” for the PVT table. When the read
pointer is N, the present motion segment starts at the coordinates written on the Nth row
of the table, and ends at the coordinates of the (N+1) row
2 .
When the time period specified by QT[N] elapses, the N segment is complete, the drive
increments the read pointer to N+1, and then reads the N+2 PVT table row in order to
calculate the parameters of the next motion segment.
The entire PVT table need not be used for a given motion. Its use is defined by the
following parameters:
Parameter Use
MP[1] Lowest valid row of the PVT table
MP[2] Highest valid row of the PVT table
MP[3] A bit field:
Bit 0 is:
0: Stop motion if read pointer reaches MP[2]
1: Continue motion when read pointer reaches MP[2]. The next row of
the table is MP[1].
Bit 1 is:
0: PVT motion not expected to terminate. Issue an exception if it does.
1: PVT motion expected to terminate. When all data in PVT table has
been used, exit PVT mode to Idle mode without issuing an emergency
object.
Figure 11-4: PVT Motion Parameters
The following flowchart depicts the basic PVT mode. It assumes that the commands
PV=N; BG;
were entered, with 1 < N < 64.
The command PV=N sets the read pointer of the table to N and specifies that the next BG
will start a PVT motion. BG then starts the motion.
The PVT table may be written online while PVT motion is being carried out. An infinite
non-periodic motion can be generated in cyclical mode (MP[3]=1) by programming the
PVT table on-the-fly.
2 The PVT mode may be cyclical, according to MP[3]. In this case, N+1 must be interpreted in
the modulo sense.