Manual

3-22 Detailed Descriptions of ACL Commands
The execution of a CF command does not affect the existing microstep locations of the
carriage, the origin, the travel limits, and the taught point. However, the CF command
affects the values reported by OC after front-panel Arrow button or GO TO ORIGIN motion
since such motion causes the Commanded position to be recomputed.
Very small values of <xcal> and <ycal>, say in the range 0.0001 through 0.01, do not
produce accurate results. For example, the sequence CF 0.001, 0.001; MA 10000,
10000; OC; produces the result 10000,10000 as expected. But then if the Arrow buttons
are used to move the carriage away one microstep and then back to the original position, an
OC will give 9929.697,9929.697.
This result differs from the first one because front-panel carriage motion forces the
Commanded Position to be recomputed from the Actual Position by dividing a microstep
value by the calibration factor. The magnitude of the error is related to the way the
calibration factors are represented internally; larger values of calibration factor give
proportionately smaller errors.
The current calibration factors can be read via the OF command.
CP Clear Patterns
This command cancels all active patterns and reinstates the "main" Origin position; i.e., the
Origin that was in effect when the first BP ("Begin Pattern") command was executed. The
pattern rotation angle is set to zero.
The action of CP is performed automatically at power up and at IN.
CR <x index>, <y index>, <x correction>, <y correction> Correction
This command installs a pair of correction offsets into the Automove System's XY Linearity
Correction Table. This table is stored in the non-volatile memory so that it retains its values
even when the power is turned off. Be sure to flip the backpanel write protect switch down
before executing the CR command.
The Automove System consults the Linearity Correction Table whenever a position
command is received via an AA, AR, MA, MR, or SP. The commanded XY position is
corrected by a small amount to produce an accurate physical motion. The table is used "in
reverse" by the OC and OT commands to convert a physical position into the corresponding
Calibrated Unit position.
The Linearity Correction Table is used in conjunction with the calibration factors as
established by the CF command. In an MA command, for example, the XY Calibrated Units
position is first rotated by the pattern angle. This rotated position is then multiplied by the
calibration factors and the (reverse-corrected) Origin is added. Then the Correction Table is
applied. Thus, the correction is with respect to the Home switches, not the Origin. This
means that the corrections can be measured over the travel of the physical system (e.g.
Automove XY table) and will be appropriately applied even though the Origin has moved.