Mode Switch – PA2/PA1

The Mode Switch controls the degree of help that may appear on the screen. There are three settings: HELP, FORMAT, and TBONLY. The PA2/PA1 key moves you to the next of these modes in a ringed sequence, from HELP to FORMAT to TBONLY, and back to HELP. The mode is displayed on the message line described above.

In the default HELP mode, entering the HP command or pressing <PF1> displays all available help. A summary of the relevant command’s syntax appears on the message line and additional help text appears below the ruler, overwriting any currently displayed information. In FORMAT mode, below-the-ruler help text is suppressed to preserve the display. In TBONLY mode, all help is suppressed to avoid table accesses not explicitly asked for by the user so that the state of an application program can be mimicked as exactly as possible for debugging. In TBONLY mode, the HP command is inoperative while the <PF1> key displays the command summary similar to Figure 94 used for the sign on screen. This is the only help available in TBONLY mode.

If it is essential to invoke DK1TDRVC so that no commands are invoked during initialization except the ones entered on the command line, the TBONLY mode can be entered directly. Enter “TBDR TBONLY” on the CICS screen to initiate the transaction.

The leftmost word on the message line of the DK1TDRVC screens indicates which of DK1TDRVC‘s three modes is in use; HELP, FORMAT, or TBONLY. Modes are switched with the PA2 key; the difference among modes is the amount of help available to the user.

When switching modes, DK1TDRVC re-initializes itself by:

  1. Resetting all fields of the command line to their state when the program was started
  2. Clearing the message area
  3. Setting abend status off
  4. Returning the library concatenation list and Command Area to its original state if invoked from tablesONLINE/CICS
  5. Getting a new system date.

It does not change the EDIT switch (see below), nor does it automatically perform any ML commands to ensure that tableBASE and DK1TDRVC have consistent library information. If libraries other than the defaults are in use, the user should issue the appropriate MLs after each mode switch.

DK1TDRVC is written to respond to any PA key as a signal to switch to the next mode, but some environments trap PA1 for their own purposes and do not pass it to applications, and not all terminals provide PA3. So, if one PA key does not work, try another.