About configuring a device list

You can configure a device list using the following methods:


Autoconfiguring a system identifies the target devices on your development platform by reading appropriate Serial Wire Debug (SWD) registers. The value of this register is usually set by the engineers that integrate the devices into a design. It is not set within the ARM devices themselves. For more information, see the ARM datasheet or technical reference manual for the processor that you are integrating.


Auto-configuring can be intrusive and stop your development platform from operating normally. If you want to connect to a target on your development platform without performing a reset and stop, you must manually add the devices to the scan chain.

When autoconfiguring a device list, debug hardware interrogates the scan chain and automatically selects the correct templates for supported ARM target devices, then adds them to the scan chain in the correct order. This takes place at the current clock speed:

  • If you are using a fixed clock speed, but debug hardware detects one or more devices that require adaptive clocking, it automatically selects adaptive clocking.

  • If you are using adaptive clocking, but debug hardware does not detect any devices that support adaptive clocking, an error message is generated. Select a fixed clock speed.

  • If the clock speed is too high, some devices on the scan chain might not be detected. If you suspect that this is happening, decrease the clock speed.


Autoconfiguration is disabled in RVConfig if the current debug hardware configuration has a platform assigned to it.

Show/hideManual configuration

You can add devices manually to a scan chain. You must do this if your development platform includes:

  • Unsupported devices. That is, devices for which no templates are provided by the debug hardware unit.

  • Supported devices that are not detectable by the debug hardware unit.

Show/hideCoreSight development platforms

If your development platform contains CoreSight devices, then autoconfiguration involves:

  1. Adding the ARM CoreSight Debug Port (ARMCS-DP) device.

  2. Reading the CoreSight ROM Table. This table contains a list of the CoreSight devices included in your development platform.

Show/hideSee also

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