2.2. Using the Cascade DataHub Viewer
The Cascade DataHub Viewer is a utility that lets you see what's happening in the datahub, and make changes to points manually. It has console, QNX, Photon, and X Windows modes.
2.2.1. Console Mode
STARTING:
Type dhview at the shell prompt to start the viewer.
NAVIGATION:
Move the selection bar by pressing the up and down arrows.
Scroll up and down a line at a time by pressing the U and D keys; or a page at a time by pressing the P and N keys or PgUp and PgDn.
MAKING CHANGES:
 | Changes are written directly to the datahub, effective as soon as the Enter key is pressed. |
Choose a point by moving the selection bar to the desired point and pressing Enter. A small dialog box opens that allows you to edit the point's value, confidence, and security.
Edit a chosen point by pressing the Backspace key to delete the existing entry; then type in the new information. Use the Tab key to move between fields. Use the Esc key to close the dialog window, ignoring any changes and keeping the original entry. Use the Enter key to enter the changes and close the dialog box.
Retransmit all points from the datahub to the viewer by pressing the R key. This is useful to see those points that were created but haven't been assigned a value, such as through a call to the Gamma function read_point or register_point.
QUITTING:
Type Q to quit the Cascade DataHub Viewer.
2.2.2. QNX Photon Mode
In addition to the features in console mode, the Photon mode of the Cascade DataHub Viewer has a search feature, and its display includes a timestamp field. It also highlights in red any locked points.
STARTING:
Type phdhview at the shell prompt to start the viewer.
NAVIGATION:
Scroll up and down by using the scrollbar, the arrow keys, or PgUp and PgDn.
Find a point by typing its name in the Search entry field.
MAKING CHANGES:
| Changes are written directly to the datahub, effective as soon as the Apply button is pressed. |
Choose a point by clicking on it. A small dialog box opens that allows you to edit the point's value, confidence, security, and locked status.
Edit a chosen point by deleting the existing entry; then type in the new information. Use the Tab key or click the mouse to move between fields. Press the Cancel button to close the dialog window, ignoring any changes and keeping the original entry. Press the Apply button to enter the changes.
Retransmit all points from the datahub to the viewer by pressing the Reload button. This is useful to see those points that were created but haven't been assigned a value, such as through a call to the Gamma function read_point or register_point.
QUITTING:
Press the circular X close button in the window title bar to quit the Cascade DataHub Viewer.
2.2.3. X Windows Mode
In addition to the features in console mode, the X Windows mode of the Cascade DataHub Viewer has fields for changing point values, permanently displayed at the bottom of the viewer. It has a search feature, and its display includes a timestamp field for every point. It also highlights in red any locked points.
 | You must have GTK to use this mode. |
STARTING:
Type xdhview at the shell prompt to start the viewer.
NAVIGATION:
Scroll up and down by using the scrollbar.
Find a point by typing its name in the Search entry field.
MAKING CHANGES:
| Changes are written directly to the datahub, effective as soon as the Apply button is pressed. |
Choose a point by clicking on it. The point's information will be displayed in the data fields at the bottom of the viewer.
Edit a chosen point by deleting the existing entry; then type in the new information. Use the Tab key or click the mouse to move between fields. Press the Clear button to remove all entries, ignoring any changes and keeping the original entries. Press the Apply button to enter the changes.
| If you change the name of a point, the Cascade DataHub Viewer will automatically create a new point in the datahub with that name and any entered values. |
Change a point type by clicking the appropriate button: String, Float, or Integer. Press the Apply button to enter the changes.
Lock or unlock a point by clicking the Toggle Lock or Locked button. Press the Apply button to enter the changes.
Write a new point by pressing the Clear button and entering the point name, confidence (usually 100) and value. Press the Apply button to enter the changes.
Retransmit all points from the datahub to the viewer by pressing the Reload button. This is useful to see those points that were created but haven't been assigned a value, such as through a call to the Gamma function read_point or register_point.
QUITTING:
Press the square X close button in the window title bar to quit the Cascade DataHub Viewer.