Troubleshoot target connections

Your DSTREAM-ST unit is built for robust performance, but problems can arise when:

  • Incompatible hardware is used with software.
  • Hardware is not configured or connected correctly.
  • Other hardware-related issues.

If you are having issues with connections to your DSTREAM-ST unit, try the following:

Check List

Things to check

Are you using the latest version of Arm Development Studio?

Download and install the latest version of Arm Development Studio.

New functionality, bug-fixes, and support for new targets are provided with every release of Arm Development Studio.

Are you using the latest firmware for your DSTREAM-ST unit?

Use the Debug Hardware Firmware Installer view in Arm Development Studio to update the firmware for your DSTREAM-ST unit.

Are all the cables connected and seated properly in the correct orientation?

Make sure all the cables are connected and seated properly.

Check that the stripe on the debug cable matches up with pin-1 of the debug connector.

Does the pin-out of the target's debug connector match the pin-out of your DSTREAM-ST unit?

Check the DSTREAM-ST System and Interface Design Reference guide for more information about connection pin outs.

Have the target and the DSTREAM-ST unit power cycled to ensure normal operating conditions?

To restore normal operating conditions, power cycle the target and your DSTREAM-ST unit.

Has the DSTREAM-ST unit booted successfully?

Observe the progress of the boot sequence to confirm that your DSTREAM-ST unit is booting properly. See DSTREAM-ST unit boot sequence for more information.

Check that the STATUS LED is glowing steady green.

If the STATUS LED flashes red, it signifies that a boot failure has occurred. See Restore a DSTREAM-ST unit to see what to do in the event of a boot failure.

Is the target system fully powered-up?

Check if the power up sequence specified by the target's documentation is followed correctly.

Illuminated LEDs on the target do not necessarily mean that the SoC and debug interface are powered. Check if there are any buttons or switches on the target which must be operated to enable the SoC and debug interface. Check your target's documentation or support channels for more information.

Does the target SoC have security features that must be disabled or unlocked during connection?

Check the documentation of the SoC for details about security features.

Are there any switches or jumper links to set on the target?

On some target boards, solder-links, jumper-links, or DIP switches must be configured to enable debug.

Check target board documentation or support channels for more information.

Is the correct debug connector used on the target board?

Some target boards use separate debug connectors for SoCs, FPGAs, and processor core supervisors.

Check if the correct debug connector is used.

Is debugging disabled in the target SoC?

Some targets disable debugging facilities for security purposes. Check if debugging is enabled on your target.

Is the target's operating system disabling the debug interface during the boot process?

Try connecting and stopping the target immediately after power up.

Try postponing the boot process using a serial connection to the target.

Is the connection attempting to load an image into the target SoC while the cores are running?

Try halting the cores through a bare-metal connection first.

Is the target's VTRef signal detected by the DSTREAM-ST unit?

Check if the TARGET LED on the DSTREAM-ST unit is glowing steady green.

Does the DEBUG LED flash when trying to initiate the target connection?

Check if the host software is communicating with the correct debug unit.

If using Arm Development Studio, try using the Identify button available in either the Debug Hardware Firmware Installer view or the Debug Hardware Configure IP view to identify and ensure that the correct debug unit is used.

Is the connection a simple Connect Only connection in the Arm Development Studio debug configuration for your target?

A simple Connect Only connection is useful to verify the connection to the hardware. This type of connection usually does not run any scripts or load any images on the target.

To start debugging, set the connection as either Debug from entry point or Debug from symbol in the debug configuration.

Is the Clock Speed (Hz) in the platform configuration set correctly?

Problems might occur if the clock speed is set too high.

Try setting the clock speed to lower frequencies in adaptive and non-adaptive clocking modes.

Are the nTRST and nSRST signals linked on the target?

Try enabling Linked_SRST_TRST in the Probe Configuration tab in Platform Configuration Editor available in Arm Development Studio.

Are initialization resets putting the target into an unwanted state?

Try disabling TResetOnInitConnect and AllowICETAPReset in the Probe Configuration tab in the Platform Configuration Editor available in Arm Development Studio.

In the Arm Development Studio debug configuration for the target, does the Target Connection option match the debug unit?

Check if the DSTREAM-ST unit is selected as the Target Connection option in the Connection tab of the debug configuration for your target.

Does the platform configuration settings for your target specify the correct debug interface mode?

Check if the LVDS Debug Interface mode is set correctly in the platform configuration settings for your target.

Is an SWD connection being attempted with hardware which only supports JTAG?

Check and correct the connection setting.

Even if the SoC supports SWD, there might be buffers on the target board which prevent bi-directional data on the TMS signal.

Are trace capture options correctly set?

Check that the trace capture settings used for the debug configuration is set correctly.

Are core trace options correctly set with the appropriate cores enabled?

Check that the core trace options used for the debug configuration is set correctly.

Is the TRACING LED lit but the DATA LED unlit?

This indicates failure to synchronize with the trace data stream.

Check if the target SoC's TPIU or I/O pins are configured correctly.

Are you having USB connectivity issues?

The DSTREAM-ST unit uses Ethernet over USB to connect to your Host PC.

On Windows 7 and Windows 10 hosts, the DSTREAM-ST unit is automatically detected as a DSTREAM-ST Network Adapter and you can view it in the Device Manager as a network adapter.

On Linux hosts, the DSTREAM-ST unit is detected as a USB network device.

The DHCP server running on your DSTREAM-ST unit assigns an IP address in the link local address range to the USB interface connected to your unit. You can use the ifconfig utility to view the IP address that your DSTREAM-ST unit has assigned to the connected USB interface on your workstation.

If you have issues with connectivity on Linux hosts, you might need to enable your USB interface in the Network Manager, or enable it in the relevant configuration files for your Linux distribution.

Note: The following instructions use usb0 as the USB interface which is connected to your DSTREAM-ST unit. If your setup differs, change it accordingly. You can use the output of the dmesg utility to view the USB interface number.

On Ubuntu hosts:

  1. Add the following text to /etc/network/interfaces:

    allow-hotplug usb0

    iface usb0 inet dhcp

  2. Restart your network service or workstation.

On Red Hat hosts:

  1. Create the following file:


  2. And add the following text to the file:




  3. Restart your network service or workstation.