Display device operations

In addition to the standard terminal control commands for sending and receiving data, several commands and lists are provided for use with display devices such as the 3270.

The commands are:
  • Print displayed information (ISSUE PRINT)
  • Copy displayed information (ISSUE COPY)
  • Erase all unprotected fields (ISSUE ERASEAUP)
  • Handle input without data (RECEIVE)
  • Handle attention identifiers (HANDLE AID)
The lists are:
  • Standard attention identifier list (DFHAID)
  • Standard attribute and printer control character list (DFHBMSCA)

For devices with switchable screen sizes, the size of the screen that can be used, and the size to be used for a given transaction, are defined by CICS® table generation. These values can be obtained with the ASSIGN command, described in ASSIGN.

Always include the ERASE option in the first SEND command, to clear the screen and format it according to the transmitted data. This first SEND with ERASE also selects the screen size to be used, as specified using the RDO option SCRNSIZE, or in the TCT. If ERASE is omitted, the screen size is the same as its previous setting, which can be incorrect.

Use the CLEAR key outside of a transaction to set the screen to its default size.