Terminal-Controlled Keys; 3270 Functions - IBM 3174 Reference Manual

Using Your ASCII Terminal
Terminal-Controlled Keys
The terminal acts Independently of the controller for the following functions (the
function of these keys Is not altered):
• Typematic operation for some or all keys on the keyboard. When a typematic
key Is pressed, Its function Is repeated while the key remains pressed. See
your terminal manual for more Information about this function.
• Setup keys.
• Local print.
• Cursor mode keys (block or underline).
3270 Functions
ATTN: The ATTN function signals an attention condition to the host (SNA only).
Using ATTN during a print IDENToperation causes the ID operation to end. The
keyboard locks, and the previous printer ID and the function not supported
messages (X -f) are displayed on the status line. You can unlock the keyboard by
using the Reset key sequence defined for your terminal and repositioning the
cursor.
Program Attention Functions (Enter, Clear, PF Keys, and PA Keys): These
functions cause the transfer of information to the host. An attention Identification
(AID) character Is sent to the host, which identifies the function causing the
transfer. (Note that the AID characters are not typematic.)
The Clear function clears all positions on the screen and positions the cursor In the
upper left corner.
Change Screen: Depending on how the 3174 Is customized, the Change Screen
function allows you to access multiple host sessions. See Chapter 1, "Getting
Started" for more details.
Cursor Movement Functions (Cursor Up, Cursor Down, Cursor Right, Cursor Left,
Cursor Fast Right, and Cursor Fast Left): Cursor Up, Down, Right, and Left move
the cursor one position at a time Into any character position. Cursor Fast Right and
Fast Left move the cursor two positions at a time. Using these functions, you can
move the cursor Into any position, including unprotected and protected fields.
All of the following functions can cause the cursor to wrap:
• If the cursor Is located In the last position of a line and you use the Cursor
Right function, the cursor moves to the first position of the next line.
• If the cursor Is located In the first position of a line and you use the Cursor Left
function, the cursor moves to the last position of the previous line.
• If the cursor Is located In the first line of the screen and you use the Cursor Up
function, the cursor moves to the last line of the screen, without changing the
column position.
• If the cursor Is located In the last line of the screen and you use the Cursor
Down function, the cursor moves to the first line of the screen, without
changing the column position.
Chapter 3. Using Your ASCII Terminal 3-9