The DSTREAM-ST unit
The DSTREAM-ST unit provides the hardware interface to connect the host computer to your target.
The rear of the DSTREAM-ST unit contains ports for connecting to the network, host PC, and the power source. It also contains the RESET button and the USER IO port.
Figure 1-1 Rear of the DSTREAM-ST unit
- Ethernet port
If you want to access your DSTREAM-ST unit over a local area network, use the Ethernet port.
The green LED indicates that the Ethernet link is up and running. The yellow LED indicates that activity is taking place. Supported data rates are: 10/100/1000 Mbps.
DSTREAM-ST is a Gigabit Ethernet (GbE) device. To achieve the maximum GbE data transfer rate:
- Your PC must support the GbE standard.
- Your network infrastructure must support the GbE standard.
- You must use the included GbE cable.
- USB 3.0 port
To connect the DSTREAM-ST unit directly to your host PC, use the USB 3.0 port.
DSTREAM-ST is a USB 3.0 device. To achieve the maximum USB 3.0 data transfer rate:
- Your PC must have a USB 3.0 port.
- You must use the included USB 3.0 data cable.
Longer or lower-quality cables might not operate at USB 3.0 data transfer rates because of higher signal loss. In this event, DSTREAM-ST reverts to USB 2.0 mode.
- USER IO port
Use the USER IO port to set up custom input or output connections to your target. See the Arm DSTREAM-ST System and Interface Design Reference Guide for more details.
- RESET Button
To reset the DSTREAM-ST unit, press and release the RESET button. The RESET button operates immediately and performs a full internal power-cycle. This also resets any attached probes.
WarningAlways use the RESET button to power-cycle your DSTREAM-ST unit. Disconnecting and reconnecting the DC plug to power-cycle your target might cause ground-loop issues.
NoteIf you continue to hold the RESET button for 10 seconds more, the STATUS LED flashes red rapidly. When you release the RESET button after this point, DSTREAM-ST reboots and defaults back to factory installed firmware. To update the firmware of your DSTREAM-ST unit, use the Debug Hardware Firmware Installer view in Arm® Development Studio.
- Power input
Connect the power adapter provided with the DSTREAM-ST unit to this port.
The front of the DSTREAM-ST unit contains ports for connecting to your target.
Figure 1-2 Front of the DSTREAM-ST unit.
- CORESIGHT 20
A high-density connector that supports 10-way or 20-way CoreSight™ standards in addition to a subset of the MIPI debug connection standards. It provides support for Serial Wire and JTAG interface modes in a 20-pin (0.05") connector.
NoteTo achieve the highest possible trace data rate, Arm recommends using the short, 15cm ribbon cable.
- ARM JTAG 20
JTAG 20 provides support for Serial Wire and JTAG interface modes in a 20-pin (0.1") connector.
This port is included for any potential future enhancement of DSTREAM-ST.
- Other connectors
Included with DSTREAM-ST are:
- Texas Instruments 14-way adapter - Used along with the Arm JTAG 20 cable, provides debug access to any target with a TI JTAG 14 header.
MICTOR adapter - Used along with the Arm JTAG 20 and CoreSight 20 cables, this adapter provides debug and trace access to any target with a MICTOR socket.
NoteTo achieve full MICTOR connectivity, you must use both the Arm JTAG 20 and CoreSight 20 cables.
- Optional adapters
The following adapters are also available for use with DSTREAM-ST. Each of these allows DSTREAM-ST to capture up to 4-bit wide ETM trace and also allow the use of separate debug and trace power domains.
- MIPI-34 adapter - This adapter connects directly to the front panel of DSTREAM-ST and is supplied with a MIPI-34 ribbon cable to provide debug and trace access to any target with a MIPI-34 header.
- MIPI-60 adapter - This adapter plugs into a target's MIPI-60 socket and converts it to a MICTOR socket for use with the DSTREAM-ST MICTOR adapter.
To obtain optional adapters, contact Arm support with your requirements.
Indicator LEDs on the top
When you power up the DSTREAM-ST unit, the LEDs on top of the unit indicate the status of the unit.
Figure 1-3 Indicator LEDs
- DSTREAM logo
The DSTREAM logo on the top of the unit illuminates and the STATUS LED begins to flash when you power up the DSTREAM-ST unit. The DSTREAM logo also flashes when you click the Identify button in the Debug Hardware Configure IP view or the Debug Hardware Firmware Installer view in Arm Development Studio.
Illuminates green to show that DSTREAM-ST is in its ready state.
If a critical error is detected, the STATUS LED illuminates as continuous red. If the STATUS LED is red, then you must reset the DSTREAM-ST unit to the factory settings before you can continue using it. If the DSTREAM-ST unit fails to boot after a reset, contact Arm support. For more information, see Restore a DSTREAM-ST unit.
Illuminates when the unit is accessing its internal flash storage.
Illuminates when a valid target VTREF is detected.
Illuminates when debug data transfer takes place.
Indicates that DSTREAM-ST is attempting to capture data and synchronize with the trace stream.
Indicates that a trigger is present in the trace data.
Indicates that trace synchronization is complete and DSTREAM-ST is capturing trace data. Trace synchronization is when the DSTREAM-ST unit aligns with the trace data stream on detection of a full synchronization packet.
Indicates an overflow-condition during trace capture. An overflow condition occurs if it has not been possible to stream trace data to the host PC at a high enough rate. For example, if the USB port is only operating in USB 2.0 mode, if the Ethernet port is only operating at 100Mbps, or if other applications on the host PC are using too much USB or Ethernet bandwidth.
In general, when streaming trace data, the best practice is to keep usage of other applications, on the host PC, to a minimum.
- TRC CLK
If the TRC CLK LED is green, it indicates that a valid trace clock is detected. This is the normal condition when capturing trace data from a target.
If the TRC CLK LED is off, then no trace clock signal is detected.
If the TRC CLK LED is red and flashing, it indicates that the received trace clock frequency is too high or too low to be captured.