ARM DSTREAM DS-5, Manual

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Setting Capture Options
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Sample Rate
The target generates periodic measurement interrupts according to the following
settings:
Normal =1kHz, Low =100Hz, and None . The Normal setting works
well for most instances. Low is recommended if you have a slow target, or if the
target is heavily loaded, as the Low setting means less intrusion by Streamline.
The Low setting does necessitate a longer capture to collect representative data.
If you set Sample Rate to None , Streamline does not force the target to generate
any periodic measurement interrupts. This ensures that Streamline has the lowest
level of intrusion on your code, but also means that resulting Analysis Reports
show only zeroes in any report columns that rely on sampling.
Buffer Mode
The default setting is unbounded streaming of target data directly to your host
using a 1MB buffer. You can also use one of the following store-and-forward
buffers:
Large 16MB
Medium 4MB
Small 1MB
If you select one of these sizes the capture ends when the buffer is full. This
prevents the latency caused by streaming data from the target to the host.
Duration The length of the capture session, in seconds. For example, enter 1:05 for 1
minute and 5 seconds. If you do not provide a value here, the capture session
continues until you stop it manually.
Call stack unwinding
Select this checkbox to ensure that Streamline records call stacks. This greatly
improves your visibility into the behavior of your target, but increases the amount
of raw data Streamline sends from the target to the host. Make sure to compile
your EABI images and libraries with frame pointers using
the
-fno-omit-frame-pointer
compilation option.
Note
Streamline supports callstack unwinding for ARM binaries created using
gcc
,
provided you compile them with frame pointers enabled. Streamline does not
support Thumb or output from
armcc
.
4.2.2 Energy Capture options
The following settings define your Energy Capture device:
Energy Capture drop-down menu
This menu has three options. Select No Energy Data Collection to turn Energy
Capture off. When you enable this option, all other Energy Capture options are
disabled. Select
ARM Energy Probe or National Instruments DAQ to match
your energy capture hardware.
Device Use this field to give Streamline the name of your target energy capture device.
Streamline attempts to auto-detect your device if this field is left blank.