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EDITR

EDITR, External Debug Instruction Transfer Register

The EDITR characteristics are:

Purpose

Used in Debug state for passing instructions to the PE for execution.

Configuration

EDITR is in the Core power domain.

Attributes

EDITR is a 32-bit register.

Field descriptions

When FEAT_AA32 is implemented and UsingAArch32():

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
hw2																hw1

hw2, bits [31:16]

Second halfword of the T32 instruction to be executed on the PE. When EDITR contains a 16-bit T32 instruction, this field is ignored. For more information, see 'Behavior in Debug state'.

Note

The hw2 field is displayed on the left. This is not the usual convention for display of T32 instruction halfwords.

hw1, bits [15:0]

First halfword of the T32 instruction to be executed on the PE.

Note

The hw1 field is displayed on the right. This is not the usual convention for display of T32 instruction halfwords.

When FEAT_AA64 is implemented and !UsingAArch32():

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
A64_Instruction

A64_Instruction, bits [31:0]

A64 instruction to be executed on the PE.

Accessing EDITR

If EDSCR.ITE == 0 when the PE exits Debug state on receiving a Restart request trigger event, the behavior of any instruction issued through the ITR in Normal access mode that has not completed execution is CONSTRAINED UNPREDICTABLE, and must do one of the following:

It must complete execution in Debug state before the PE executes the restart sequence.
It must complete execution in Non-debug state before the PE executes the restart sequence.
It must be abandoned. This means that the instruction does not execute. Any registers or memory accessed by the instruction are left in an UNKNOWN state.

EDITR ignores writes if the PE is in Non-debug state.

EDITR can be accessed through the external debug interface:

Component	Offset	Instance
Debug	0x084	EDITR

Accessible as follows:

When DoubleLockStatus(), or !IsCorePowered(), or OSLockStatus(), accesses to this register generate an error response.
When SoftwareLockStatus(addrdesc), accesses to this register are WI.
Otherwise, accesses to this register are WO.

2026-03-26 20:27:25, 2026-03_rel

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
hw2																hw1

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
hw2																hw1

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
hw2																hw1