A.1.1. Serial wire or JTAG Debug Port signals

Table A.1 shows the Serial Wire or JTAG Debug Port (SWJ-DP) signals.

Table A.1. Serial wire and JTAG debug port signals

Name

Type

Clock domain

Description

ntrst

Input

swclktck

TAP asynchronous reset.

npotrst

Input

swclktck

JTAG powerup reset and Serial wire powerup reset.

swclktck

Input

NA

Serial wire clock and TAP clock.

swditms

Input

swclktck

Serial wire data input and TAP test mode select.

tdi

Input

swclktck

JTAG TAP data in or alternative input function.

dapresetn

Input

dapclk

DAP asynchronous reset active-LOW.

dapclk

Input

dapclk

DAP clock.

dapclken

Input

dapclk

DAP clock enable.

daprdata[31:0]

Input

dapclk

DAP read data.

dapready

Input

dapclk

DAP data bus ready.

dapslverr

Input

dapclk

AP slave error response.

cdbgpwrupack

Input

None

Debug power domain up acknowledge.

csyspwrupack

Input

None

System power domain up acknowledge.

cdbgrstack

Input

None

Debug reset acknowledge to reset controller.

targetid[31:0]

Input

None

Target ID for SW multi-drop selection.

instanceid[3:0]

Input

None

Instance ID for SW multi-drop selection.

swdo

Output

swclktck

Serial wire data output.

swdoen

Output

swclktck

Serial wire data output enable.

tdo

Output

swclktck

JTAG TAP data out.

ntdoen

Output

swclktck

TAP data out enable.

dapcaddr[15:2]

Output

dapclk

Compressed DAP address.

dapwrite

Output

dapclk

DAP bus write.

dapenable

Output

dapclk

DAP enable transaction.

dapabort

Output

dapclk

DAP abort.

dapsel

Output

dapclk

DAP transaction select.

dapwdata[31:0]

Output

dapclk

DAP write data.

cdbgpwrupreq

Output

NA

Debug power domain powerup request.

csyspwrupreq

Output

NA

System power domain powerup request.

cdbgrstreq

Output

NA

Debug reset request to reset controller.

jtagnsw

Output

swclktck

HIGH

If JTAG selected.

LOW

If SWD selected.

jtagtop

Output

swclktck

JTAG state machine is in one of the four modes:

  • Test-Logic-Reset.

  • Run-Test/Idle.

  • Select-DR-Scan.

  • Select-IR-Scan.


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