11.4.5. SWO identification registers

The identification register values specific to the SWO are:

Authentication Status Register, 0xFB8 [7:0]

This register reports the required security level for operation, and is set to 0x00 for functionality not implemented.

Device ID, 0xFC8

Table 11.4 shows the SWO Device ID Register bit assignments.

Table 11.4. Device ID Register bit assignments

[31:12]0x00000Reserved RAZ/SBZP.
[11]1UART/NRZ Serial Wire Output supported.
[10]1Manchester Serial Wire Output supported.
[9]1Synchronous trace port (trace clock and data) not supported.
[8:6]0x2FIFO Size (Power of 2). A value of 2 gives a FIFO size of 4 (22).
[5]1Indicates the relationship between ATCLK and TRACECLKIN. 0x1 indicates asynchronous. The SWO always assumes the relationship is asynchronous, and this bit reads as 1.

Hidden Level of Input multiplexing.

When non-zero this value indicates the type/number of ATB multiplexing present on the input to the ATB.

Currently only 0x00 is supported (no multiplexing present). This value is used to assist topology detection of the ATB structure.

Device Type Identifier, 0xFCC

A value of 0x11 identifies this device as a trace sink (0x1) and as a kind of TPIU (0x1).

JEP106 Identity, 0xFD0 [3:0], 0xFE8 [2:0], and 0xFE4 [7:4]

JEP106 continuation code, 4-bits, JEP106 Identity code, 7-bits. ARM designed components take the value 0x4, continuation code, and 0x3B, identity code.

Part Number, 0xFE4 [3:0], 0xFEO [7:4], and 0xFEO [3:0]

A value of 0x914 identifies the part as a Single Wire Output.

Revision, 0xFE8 [7:4]

The value indicates the revision of the component. See Table 1.1 for the current revision of this component.

Customer Modified, 0xFEC [3:0]

This component has no customer modified RTL and takes the value 0x0.

RevAnd, 0xFEC [7:4]

This is changed from 0x0 if any alterations have to be made to the device during layout.

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