NorthStar 958 Operator's Manual page 59

Chapter 4 - Using the Chart Screen
Figure 1 shows the vessel heading northwest on the first leg
from the first waypoint to the second one. The chart's viewing
angle is set to north-up. Notice the direction of the
north-pointing arrow in the upper right corner.
Figure 2: Course-up chart angle (second leg going east)
Figure 2 shows the same chart, but with the chart's viewing
angle now set to course-up and the vessel on a slightly
different course than the second route leg. Notice the new
direction of the north-pointing arrow.
Figure 3: Leg-up chart angle (third leg going south)
958 Operator's Manual, Rev. A Page 51