Reference Manual

PMAC 2 Software Reference
PMAC On-Line Command Specification 211
as integer numerical constants in text form. The units of these entries are 1/16 count, and the
entries must be integer values. The first entry is the correction at one column spacing from
the zero position of the RowMotor, and the zero position of the ColumnMotor. The
second entry is the correction at two column spacings from the zero position of the
RowMotor, and the zero position of the ColumnMotor, and so on. Entry number
Columns is the correction at RowSpan counts of the RowMotor, and at the zero position
of the ColumnMotor (this entry should be zero if you wish to use the table along the edge,
to match the implied zero correction at the origin). These entries should be considered as
constituting “Row 0” of the table.
The next entry (entry Columns+1, the first entry of Row 1) is the correction at the zero
position of the RowMotor, and one row spacing of the ColumnMotor. The following
entry is the correction at one column spacing of the RowMotor and one row spacing of the
ColumnMotor. The entry after this is the correction at two column spacing of the
RowMotor and one row spacings of the ColumnMotor., and so on. The last entry of Row
1 (entry 2*Columns+1) is the correction at one row spacing of the RowMotor, and
RowSpan counts of the ColumnMotor.
Subsequent rows are added in this fashion, with the corrections of the entries for Row n being
at n row spacings from the zero position of the ColumnMotor. The last row (row Rows)
contains corrections at ColumnSpan counts of the ColumnMotor.
The size of the table is limited only by available data buffer space in PMAC’s memory.
The following chart shows the order of entries into a 2D table with r rows and c columns,
covering a span along the row motor of RowSpan, and along the column motor of ColSpan:
Column Motor
Position v Col 0 Col 1 Col 2 (Col j) Col c
Row Motor
Position >
0 RowSpan
c
2*RowSpan
c
RowSpan
Row 0 0 [0] E
1
E
2
… E
c
Row 1 ColSpan
r
E
c+1
E
c+2
E
c+3
… E
2c+1
Row 2 2*ColSpan
r
E
2c+2
E
2c+3
E
2c+4
… E
3c+2
(Row i) … … … (E
ic+I+j
) …
Row r ColSpan E
rc+r
E
rc+r+1
E
rc+r+2
E
rc+r+c
There are several important details to note in the entry of a 2D table:
• The number of rows and number of columns is separated by a period, not a comma.
• The correction to the target motor at the zero position of both source motors is zero by
definition. This is an implied entry at the beginning of the table (shown by [0] in the
above chart); it should not be explicitly entered.
• Consecutive entries in the table are in the same row (except at row’s end) separated by
one column spacing of the position of the first source (row) motor.
• Both Row 0 and Row r must be entered into the table, so effectively you are entering
(r+1) rows. If there is any possibility that you may go beyond an edge of the table,
matching entries of Row 0 and Row r should have the same value to prevent a
discontinuity in the correction. Row r in the table may simply be an added row beyond
your real range of concern used just to prevent possible discontinuities at the edges of
your real range of concern.
• Both Column 0 and Column c must be entered into the table, so effectively you are