An EAD (two bytes) is associated with each display position on a presentation space and follows each display position (or an EAB if it exists) when the EAD option is used. The bit definition of EAD's is shown below.
Byte 1
Bit Character Position Field Attribute Position
--- ------------------ ------------------------
0 DBCS character Reserved
1 1st byte of DBCS char Reserved
2 SO SO/SI exist (3270 only)
3 SI Bit 3-4: Field type (5250 only)
bit 34 7
4 Dead Position 00 0 Default (accepts only SBCS)
(such as the last 00 1 Reserved
byte of an odd 01 0 DBCS Only Field
length DBCS field) (accepts only bracketed
DBCS*)
01 1 Graphic data field
(accepts only pure DBCS)
10 0 DBCS Either Field
(accepts either only SBCS or
bracketed DBCS*)
10 1 Reserved
11 0 DBCS Open Field
(accepts mixture of SBCS and
DBCS*)
11 1 Reserved
5 Reserved SO/SI creation enabled (3270 only)
(i.e. SBCS/DBCS Mixed Field)
6 Reserved Character attribute(s) exists
(i.e. SA Order used)
7 Reserved Extended bit for alternative meaning for
Bit 3 and 4.
Note: *) Bracketed DBCS string is a DBCS string bracketed
with SO and SI, i.e. SBCS/DBCS mixed string that has
no SBCS characters.
**) DBCS Graphic Field was supported from OS/400
V2R3 and CM/2 1.1. Bits 4 and 7 are on if the field
attribute byte is for this type of field.
expansion of 5250 emulation.
Byte 2
Bit Character Position Field Attribute Position
--- ------------------ --------------------------
0 Reserved Left vertical line (3270 only)
1 Reserved Overline (3270 only)
2 Reserved Right vertical line (3270 only)
3 Reserved Underline (3270 only)
4 Left vertical line Left vertical line
5 Overline Overline
6 Reserved Reserved
7 Reserved Reserved