Intel 121748-001 manual I I I, Z I Z I Z I Z I Z Ibglibgm

8086 Object Module Formats Version 4.0

A Name Index with value zero carries special siqnificance: it specifies all ~ames. (Note: Name Indices with zero value may not occur in other record types.)

If the first byte of the DESCRIPTOR contains 0FBH. then the DESCRIPTOR contains 3 more fields. which are the LTL OAT field. the

maximum length of the qroup, and the lenqth of the qroup. This

descriptor, if present. must· precede all other descriptors in the record. There may be at most one descriptor of this type in a

GRPDEF record. There may not be any absolute component in the qroup. A seqment can not be in two such qroups.

The LTL DATA field has the followinq format:

*********************************

* I I I I I I , *

*Z I Z I Z I Z I Z I Z IBGLIBGM*

*I I I I I I I *

*********************************

Zis indicate that these I-bit fields have not currently been

assigned a function. These bits are required to be zero.

BGL (Biq Group Lenqth) is a I-bit subfield that. if 1.

specifies that the Group lenqth is exactly 64K. In this case the GROUP LENGTH subfield must contain zero.

BGM (Biq Group Maximum Lenqth) is a I-bit subfield that, if 1, specifies that the maximum qroup length is exactly ~4K. In this case the MAXIMUM GROUP LENGTH subfield must contain zero.

The GROUP LENGTH subfield specifies the length of the group that has been determined after the Group is ~locatedM, and the

seqments in the group arc put in contiquous memory area. All fixups have been performed relative to the base of the Group.

The MAXIMU~ GROUP LENGTH subfield	.	.~
	specifies the maximum	lenqth
of the qroup that has been determined	after the Group is ~located",
using the maximum lenqths of the segment components.

·If the first byte of the DESCRIPTOR contains 0FAH, then the DESCRIPTOR contains the address of the Group. Once a Group has been

LOCATEd. it has an address chosen by LOCArrE-8f), relative to which

all fixups have been performed. If fixups relative to the Group base are required after LOCATE-8~has assiqned an address to the Group then the FRAME. NU~BER should be used as the base. The address of the Group is also available for debuqqinq systems such as ICE. If a Group has been assiqned an address by LOCATE-86 then it is absolute and this descriptor must precede all other descriptors in

the record. There may be at most one descriptor of this type in a GRPDEr"' reco rd.

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