Terminal and user operating modes

A terminal can be in more than one mode at the same time.

Possible modes for a terminal or user include:
Response Mode
Response mode is established through static terminals, ETO users, or transaction specifications. Response mode can be used with full function or Fast Path processing. In response mode, after the entry of an input message, the terminal is locked until a reply is received, and no additional incoming data is accepted.
Definitions:
  • For operator-driven terminals like 3270s, locked means that the keyboard is locked.
  • For programmable terminals like LUPs, locked means that IMS delays the acknowledgment of the input message until the output message is ready to be sent.

For LU 6.2, the originator of the transaction must issue a Receive command to get the response message (synchronous output). Failure to do so is treated as a protocol violation. Depending on the system, the application program could fail and IMS could send an error message.

Terminal-response mode is terminated when the response has been sent and dequeued. If Fast Path is used, terminal-response mode is automatically continued following an IMS failure, when a static terminal logs off, or when an ETO user signs off. If full-function operation is used, terminal-response mode is terminated when IMS is restarted, when a static terminal logs off, or when an ETO user signs off, unless the terminal or user is defined with both SRMDEF=LOCAL and RCVYRESP=YES, in which case the full-function response mode is recoverable after either a terminal logoff or a user signoff.

The ETO user, not the terminal, is in response mode. If the user signs off and Fast Path is used, response mode is recovered for the user, but the terminal is no longer in response mode. The user cannot enter another transaction until the response to the first transaction is received.

Conversation Mode
After you enter a transaction that is defined using the SPA= parameter on the TRANSACT macro, the terminal is in conversation mode. While the terminal is in conversation mode, other transactions cannot be entered from that terminal. However, the terminal is not locked, in the same sense that response mode locks the terminal. The terminal remains in conversation mode until the conversation is terminated, when the message has been sent and dequeued, and the application program has placed blanks in the transaction code field in the scratch pad area (SPA).
A conversation can abnormally terminate under the following conditions:
  • When an application program abends
  • When the IMS MTO issues an /EXIT command, a /START NODE command, or a /START USER command
  • When an inconsistent definition exists in the application program between IMS and MSC

For LU 6.2, all iterations of the IMS conversation must use the same LU 6.2 conversation; each iteration of the IMS conversation is demarcated by using the LU 6.2 CMPTR (Prepare_To_Receive) call. If the LU 6.2 conversation ends prior to the end of the IMS conversation, the IMS conversation is abnormally terminated.

The ETO user, not the terminal, is in conversation mode.

Exclusive Mode
A terminal is placed in exclusive mode when the /EXCLUSIVE command is issued. The Exclusive mode:
  • Restricts the output received by the terminal.
  • Remains with ETO users after they sign off. ETO users that sign off while they are in exclusive mode remain in exclusive mode when they sign on the next time.
  • Terminates with an /END or /START NODE command.
Lock Mode
Lock mode prevents a terminal from sending and receiving messages. A terminal, node, or logical terminal (LTERM) is placed in lock mode when the operator issues the /LOCK command. Lock mode is reset by issuing the /UNLOCK command.
Test Mode
Test mode ensures that any input message entered into a terminal is transmitted back to the terminal. A node is placed in test mode by the /TEST command. Test mode is reset by an /END command or a /START command. Test mode is not significant and is not carried across restart and ETO signoff and signon.