ARM DSTREAM-ST - About Trace Signals; Figure 2-5 Clock Waveforms; Table 2-6 TRACECLK Frequencies

2.4 About trace signals
Data transfer is synchronized by the TRACECLK signal.
Clock frequency
For capturing trace port signals synchronous to TRACECLK, the DSTREAM-ST trace feature supports
up to 600Mbps per trace signal using DDR clocking mode.
Note
To achieve the maximum trace data rate, use the short (15cm) cable provided with DSTREAM-ST.
The following figure and table describe the timing for TRACECLK:
Tperiod
Twh Twl
Figure 2-5 Clock waveforms
Table 2-6 TRACECLK frequencies
Parameter DSTREAM-ST Description
Tperiod (min) 2.08ns Clock period
Twh (min) 1.0ns High pulse width
Twl (min) 1.0ns Low pulse width
Switching thresholds
The trace probe detects the target signaling reference voltage (VTRef) and automatically adjusts its
switching thresholds to VTRef/2. For example, on a 3.3V target system, the switching thresholds are set
to 1.65V.
Hot-plugging
If you power-up the DSTREAM-ST unit when it is plugged into an unpowered target, or if you plug an
unpowered DSTREAM-ST unit into a powered target, trace functionality is not damaged.
If you connect an unpowered DSTREAM-ST unit to a powered target, there is a maximum leakage
current into the DSTREAM-ST unit of ±10μA on any of the debug or trace signals.
2 ARM
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DSTREAM-ST target interface connections
2.4 About trace signals
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