IBM 3708 Description page 179

Flags
This is a I-byte field that is broken down into eight I-bit flags. Each flag is set to
either 1 or 0, and the 8 bits together form a hexadecimal value. Refer to the
appendixes in IBM Network Conversion Unit Planning and Installation to determine
the correct hexadecimal value for the set of flags that you need.
The bits are numbered I through 8 and have the following meanings:
Bit I-ANSI x3.64
If this set to 1, the terminal supports ANSI x3.64 formats. If this bit is set
to 0, ANSI x3.64 is not used.
Bit 2-Status line
If this bit is set to 1, the terminal has an addressable information area
separate from the normal screen display area on which the 3708 can display
its status line. For example, when the terminal is operating in 24 x 80
(model 2) mode, the 3708 status line would appear on line 25. In this case,
the START/STOP/ACTIVATE STATUS LINE sequences described in
"Terminal Control Section" are used to control the terminal's information
area.
If this bit is set to 0, the 3708 uses the last line of the normal screen display
area for the status line information. For example, when the terminal is
operating in 24 x 80 (model 2) mode, the status line would appear on line
24.
Bit 3-Scroll
If this bit is set to I, the terminal shifts the entire screen of data up one line
when a character is sent to the last column of the last line on the screen.
For this case, the 3708 never sends a character for display in the last
character position on the screen.
If this bit is set to 0, the 3708 sends characters for display in the last
character position on the screen.
Bit 4-Extended Key Sequences
If this bit is set to I, the extended terminal table function is required for this
terminal. It is required for terminals that can send more than 3 characters
per keystroke. It is supported for the IBM 3151, IBM 3161, IBM 3162,
IBM 3163, IBM 3164, VT220, and FALCO 500. Refer to IBM 3708
Network Conversion Unit Planning and Installation for more information.
Bit 5-Field Attribute Byte
Terminals support two types of attribute processing to determine field
characteristics: character attributes and field attributes. A terminal with
character attributes remembers the current attribute setting, like
highlighting, until it is changed. Character attributes do not occupy a screen
character position. To support character attributes, bit 5 should be set to O.
Field attributes occupy a screen position, much like 3270 displays. Unlike
character attributes, field attributes are remembered and need to be rewritten
only when they change. Whenever a field changes, the cursor must be
positioned at the attribute position to change or eliminate it. To support
field attributes, bit 5 should be set to 1.
If this bit is set to 1, the terminal being used reserves a position on the
screen display every time a field attribute sequence is transmitted by the
3708. Of the default terminal tables, the WY-50® is the only one that
operates in this manner. If this bit is 0, the terminal does not reserve a
position of the screen for field attributes.
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IBM 3708 Description