Automatic Skip - IBM 3708 Description

Automatic Skip
i
Some ASCII terminals do not
s~pport
intensified, or "highlighted" characters. For
these terminals, fields defined by the host as intensified appear the same as other
fields.
Detectable/Nondetectable: Displayed data in a detectable field can be detected by
the selector light pen. The 3708 does not support light pens, but does provide the
ability to emulate the light pen using the CURSR SEL function.
Table 4-6. Attribute Character Definition
EBCDIC Bit Field Description
0,1 Value determined by contents of bits 2-7.
2
o
=
Unprotected
1
=
Protected
3
o
=
Alphameric
1
=
Numeric (causes automatic upshift of data entry
keyboard).
Note: Bits 2 and 3 equal to 11 cause an automatic skip. See
"Automatic Skip"
4,5 00
=
Display/not selector-light-pen detectable
01
=
Display/selector-light-pen detectable
10
=
Intensified display/selector-light-pen-detectable
11
=
Nondisplay, nonprint, nondetectable
6 Reserved
7
Modified Data Tag (MDT); identifies modified fields during
Read Modified command operations.
o
=
Field has not been modified.
I
=
Field has been modified by the operator. Can also
be set by program in data stream.
Because the 3708's internal representation of the attribute byte is as a byte in the
device buffer having the high order bit on, only 7-bit data can be supported for 3270
LU type 2 or LV type 3 data streams.
Upon entry of a character into the last character location of an unprotected field,
the cursor is repositioned according to the attribute character describing the next
field:
• If the next field is alphanumeric, or numeric and unprotected, the cursor is
positioned to the first character location in the field (that is, the attribute
character location is skipped).
• If the field is numeric and protected, the cursor skips that field, and is positioned
at the first character location of the next unprotected field.
4-32
IBM 3708 Description