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JTAG Device Chain

The JTAG Device Chain section displays one or more debug targets connected through the JTAG interface. The IDCODE, Device Name, and IR Length are displayed automatically for each device.

Target Driver Setup - JTAG Device Chain

Manual Configuration allows identifying undetected JTAG devices. Specify the instruction register length (IR len) of each device in the JTAG device chain.

AP specifies the identifier of the Access Port in multi-core devices with a single Debug Port.

  • The AP value range is 0 to 255.
  • For single core devices, set AP to 0 (default).
  • For a multi-core device, core 0 is expected to have AP=0 and core 1 AP=1. However, the port identifiers are specified by the device manufacturer.

If AP contains an invalid identifier, the error message "Invalid ROM Table" is shown whenever a debuging session is started.


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