3.3.3.4 Data export
Use the following BCU command-line options to export data:
•
[-dump]
outputs the power data to the terminal in the CSV format. The file is named
monitor_record.csv
.
•
[-dump=filename]
outputs the data and names the file as
filename.csv
.
The interval of data sampling while using the data export command is related to the computer performance, system version, and
number of sampled power rails.
For Windows OS, it also relates to the refresh settings. You can set the refresh frequency to less than 0.5 Hz using the [-hz=value]
option and disable the TUI display using the [-nodisplay] option to achieve a higher sample rate.
For Linux OS, the refresh settings have no impact on the sample rate.
The BCU can achieve the following minimum sampling interval:
• 20 ms/sample (50 samples/s) for all 27 power rails at the same time
• 4 ms/sample (250 samples/s) for 4 rails on one PAC1934 monitor (M1 to M8)
See
for the corresponding power rails for monitors M1 to M8. See
for how to reduce the exported
power rails with the “show_id” parameter.
The export data command examples are as follows:
• For Linux OS:
$ sudo ./bcu monitor -dump=filename -board=imx8mpevkpwra1
• For Windows OS:
.\bcu.exe monitor -nodisplay -hz=’0.5’ -dump=filename -board=imx8mpevkpwra1
3.3.3.5 Sense resistance reconfiguration
The BCU software supports the customer configuration changes to the physical measurement hardware. The sensing resistors
may have to be changed on the PWR board to achieve the best measurement for your specific testing. The BCU software provides
a simple method to define the new sensing resistors' values (Rsense) for a user-defined measurement range.
PAC1934 supports a 100-mV full-scale voltage-sense range with 16-bit resolution. Thus, the full-scale current can be calculated
as follows:
Measurement range (mA) = 100mV / Rsense (ohm)
The BCU software configurations are stored in the
config.yaml
file, which is in the BCU software install folder. This file is created
by the BCU software upon the first execution of the BCU. Open the
config.yaml
file and find the text beginning with “boardname:
imx8mpevkpwra1”, as follows:
boardname: imx8mpevkpwra1
mappings:
- vdd_arm : { rsense1: 20 , rsense2: 5010 , show_id: 1 }
#Range: rsense1=>5000.0mA, rsense2=>20.0mA
- nvcc_dram_1v1 : { rsense1: 50 , rsense2: 2050 , show_id: 2 }
#Range: rsense1=>2000.0mA, rsense2=>48.8mA
- vsys_5v : { rsense1: 20 , rsense2: 420 , show_id: 3 }
#Range: rsense1=>5000.0mA, rsense2=>238.0mA
- vdd_soc : { rsense1: 10 , rsense2: 1010 , show_id: 4 }
#Range: rsense1=>10000.0mA, rsense2=>100mA
…
…
When a physical sense resistor is changed, the "rsense1" or "rsense2" values (in milliOhms) can be updated within the
config.yaml
file to match the new resistor value.
Do not modify any spaces within the
config.yaml file.
ATTENTION
NXP Semiconductors
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