Specifications

100 Chapter 6 - Command Reference

Scaling ('S','s')

Function: Provides access to the on-board coordinate scaling facilities of the

controller.

Scaling is discussed in the tutorial in Chapter 4, and an example is given in Chapter

The Scaling command has several functions:

Setting the Scaling Points from the Host

Scaling is accomplished by the host transmitting a range of coordinates, typically

equivalent to the display resolution. These coordinates are then converted by the

controller into an internal Offset, Numerator, and Denominator format.

AXIS specifies the coordinate axis to be scaled by using upper-case ASCII

characters 'X','Y', or 'Z'.

LowPoint and HighPoint are signed integers specifying an axis range. For

example, if two scaling points are specified as (XLow,YLow) and (XHigh,YHigh),

LowPoint = XLow and HighPoint = XHigh for the X-axis. If a HighPoint value is

greater than a LowPoint value, software axis inversion is performed.

Querying the Scaling Parameters

axis specifies the coordinate axis by using lower-case ASCII characters 'x','y', or 'z'.

Scaling parameters are returned in the controller's internal Offset, Numerator, and

Denominator format. These values can be saved and later restored directly in this

format.

Note there is no way to directly query the LowPoint and HighPoint values. These

values can be calculated by the following formulas:

LowPoint = Offset

HighPoint = LowPoint + Numerator

Setting the Scaling Parameters as Offset, Numerator, and Denominator

This command is used to restore scaling parameters previously queried from the

controller.

axis specifies the coordinate axis to be scaled by using lower-case ASCII

characters 'x','y', or 'z'.