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TRCSEQSTR, Trace Sequencer State Register

The TRCSEQSTR characteristics are:

Purpose

Use this to set, or read, the Sequencer state.

Configuration

External register TRCSEQSTR bits [31:0] are architecturally mapped to AArch64 System register TRCSEQSTR[31:0].

This register is present only when FEAT_ETE is implemented, FEAT_TRC_EXT is implemented, and TRCIDR5.NUMSEQSTATE != '000'. Otherwise, direct accesses to TRCSEQSTR are RES0.

Attributes

TRCSEQSTR is a 32-bit register.

Field descriptions

Bits [31:2]

STATE, bits [1:0]

Accessing TRCSEQSTR

Must be programmed if TRCRSCTLR<a>.GROUP == 0b0010 and TRCRSCTLR<a>.SEQUENCER != 0b0000.

Writes are CONSTRAINED UNPREDICTABLE if the trace unit is not in the Idle state.

Reads from this register might return an UNKNOWN value if the trace unit is not in either of the Idle or Stable states.

TRCSEQSTR can be accessed through the external debug interface:

Accessible as follows:

• When OSLockStatus(), or !AllowExternalTraceAccess(addrdesc), or !IsTraceCorePowered(), accesses to this register generate an error response.
• Otherwise, accesses to this register are RW.

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

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