TAL Reference Manual

Privileged Procedures
TAL Reference Manual—526371-001
15-6
Usage Consideration
index and offset
are equivalent INT values in the range 0 through 63.
structure-layout
is a BEGIN-END construct that contains declarations for structure items.
Usage Consideration
If you specify an indirection symbol (., .SG, or .EXT), the structure behaves like a
structure pointer. If you do not specify an indirection symbol, the structure has direct
addressing mode.
Example of 'SG'-Equivalenced Definition Structure
The following example declares a definition structure equivalent to location SG[10] in
the system global data area:
STRUCT def_struct = 'SG'[10];
BEGIN
STRING out;
FIXED up;
REAL in;
END;
'SG'-Equivalenced Referral Structure
The 'SG'-equivalenced referral structure declaration associates a referral structure with
a location relative to the base address of the system global data area.
VST1504.vsd
(
[
index
]
+
offset
-
=
referral
identifier
STRUCT
.
.SG
;
)
.EXT
'SG'