Gets the display scale of the trend tag being plotted by a specified pen.
TrnGetScale(AN, Pen, Percent)
The AN of the chosen trend.
The trend pen number:
0 - The pen currently in focus
1...8 - Pen1. . .Pen8
The percentage of the full scale, from 0 to 100.
The scale of the trend tag being plotted by Pen. If AN or Pen is invalid, 0 (zero) is returned and an error code is set.
! For the trend at AN20
! Displays the zero scale of the focus pen.
! Displays the 50% scale of the focus pen.
! Displays the full scale of the focus pen.