1.4 The DSTREAM unit

The DSTREAM unit provides the hardware interface to enable a software debugger to control and trace multiple devices.

The unit has ports at the rear for connecting to the host computer and to a power source. These ports are shown in the following figure.
Figure 1-1 Rear of DSTREAM unit
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The LEDs at the bottom of the Ethernet port display information about Ethernet speed and activity:
  • The green LED shows the Ethernet speed. When Off, it indicates a speed of 10Mbps, and when On indicates a speed of 100Mbps.
  • The yellow LED indicates that activity is taking place.
The RESET button resets the DSTREAM unit when required:
  • Press and hold the RESET button until the STATUS LED starts to flash green rapidly. If you release the RESET button at this point, a normal reboot occurs.
  • If 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 reboots and enters a recovery mode, which enables you to update firmware.
The ports at the front of the unit are shown in the following figure.
Figure 1-2 Front of DSTREAM unit
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The AUX port is included for future enhancement of the product.
Ethernet, USB and probe cables are supplied to connect the DSTREAM unit to the host computer, and to the target hardware.
The following figure shows the location and name of each of the indicator LEDs.
Figure 1-3 Indicator LEDs
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When you power-up the DSTREAM unit, the DSTREAM logo on the top of the unit illuminates and the STATUS LED begins to flash. The STATUS LED remains illuminated to show that DSTREAM is in its ready state.
The DSTREAM logo flashes for five seconds when you use the Identify tool.
The LEDs representing the DSTREAM debug feature have the following functions:
STATUS
The STATUS LED illuminates as continuous red if a critical error is detected. You must reboot DSTREAM before you can continue using it. To do this, press and hold the RESET button for approximately three seconds, then the STATUS LED turns off.
FLASH
The FLASH LED illuminates green to denote that the unit is accessing its internal flash storage.
TARGET
The TARGET LED illuminates when a target VTref is detected using the probe.
DEBUG
The DEBUG LED illuminates green when debug data transfer is taking place.
The LEDs representing the DSTREAM trace feature have the following functions:
TRACING
The TRACING LED indicates that tracing is in progress.
TRIGGER
The TRIGGER LED indicates that a trigger is detected.
DATA
The DATA LED indicates that there is valid data in the data buffer.
FULL
The FULL LED illuminates when a sufficient amount of trace data has been captured to fill the defined buffer size. The buffer then wraps, and continues to capture trace data, overwriting the original trace data captured.
TRC CLK
If green, the TRC CLK LED indicates that a valid trace clock is detected. If red, the TRC CLK LED indicates that there is a problem with the trace clock.
If the probe TRC CLK LED is green and the DSTREAM unit TRC CLK LED is red then the target is outputting a trace clock but the DSTREAM unit is unable to lock on to it. Possible causes for this are that the clock frequency is too high or that the clock frequency is varying too much.

Note

The DSTREAM unit contains an internal cooling fan that operates to control the internal temperature when necessary. Do not obscure the ventilation panels on the front and back of the DSTREAM unit.
Related concepts
1.5 The DSTREAM probe
1.7 The DSTREAM firmware
1.8 The DSTREAM host software
Related tasks
1.11 Restoring a DSTREAM unit that fails to boot
1.9 Troubleshooting your DSTREAM unit
2.5 Tracing with DSTREAM
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