How to load programmed symbol buffers

If the operator knows the programmed symbol buffers need to be loaded (because the device was just turned on), the operator should enter a response mode transaction that loads the programmed symbols.

Make available, to all users at the installation, a user-written application program to load the programmed symbols. The first part of the message sent by this application program should be the programmed symbol data stream, and the remainder should be some user data displayed at the device (such as THE PROGRAMMED SYMBOL LOAD FOR programmed-symbol-name COMPLETE). The user data displayed at the device informs the terminal operator when the programmed symbols have been loaded. This application program should use the MFS bypass option, because the write structured field (WSF) 3270 command used to send the programmed symbol message is only supported by IMS through the MFS bypass option.

When the programmed symbol buffers that are to be loaded include a printer or a different display, other techniques must be used. Programmed symbol buffer loads are restricted to 3 KB for BSC-attached devices.

For example, the following shows the loading of a programmed symbol buffer using an automated operator interface (AOI) application program.

Procedure

  1. The operator at display A enters a transaction (response or conversational) requesting programmed symbol loads for display A, printer B, and display C.
  2. Another AOI transaction assigns LTERMs for printer B and display C, temporarily, to a special PTERM. The AOI program assigns dummy LTERMs to printer B and display C.
  3. The AOI program inserts a programmed symbol message to the dummy LTERMs of printer B and display C.
  4. The AOI program sends programmed symbol messages to display A.
  5. The operator visually verifies messages on both displays and the printer and confirms that the transaction executed correctly.
  6. Another AOI transaction reassigns LTERMs to their original status.