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Grabserial - python-based serial dump and timing program - good for embedded Linux development


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Grabserial - python-based serial dump and timing program - good for embedded Linux development

See for documentation and examples.

For help with command line options, use: grabserial -h


If you have the python 'serial' module, you can just place grabserial in a directory on your path, or add the directory containing grabserial to your path, or just invoke grabserial directly.

This should work:

$ sudo cp grabserial /usr/local/bin
$ grabserial

You can also install this as a python module with: 'python install' (Some users have reported problems with this - let me know if it doesn't work for you.)


$ grabserial -d /dev/ttyUSB0 -e 30 -t -m "^Linux version.*"

Grab serial input for 30 seconds (-e 30), displaying the time for each line (-t), and re-setting the base time when the line starting with "Linux version" is seen.

$ grabserial -d COM4 -T -b 115200 -e 3600 -Q -o "%" -a

Log serial data from COM4, with system timestamp (-T) with settings 115200:8N1:xonxoff=0:rtscts=0 (-b 115200) to the output file "2017-06-13T22:45:08" (-o "%"), for 1 hour (-e 3600) and then restart (-a) to create new log.

$ grabserial -d /dev/ttyUSB2 -C -q "nsh>" -c free

Send the 'free' command to the serial port (-c free), and show output until a prompt of "nsh>" is seen (-q "nsh>"). Suppress the command echo and shell prompt (-C).

$ grabserial -v -d COM10 -B 9600 -T -R 1h -o "c:\log\%Y-%m-%dT%H-%M-%S.txt"

Start a continous recording with timestamps for each line (-T) (eg: [09:07:47.330944 0.007000]) and create a new file with timestamp %Y-%m-%dT%H-%M-%S at the specified location every hour (-R).

Notice - New Default ‘-o’ Behavior

Using the '-o' option, as in the second example above, with a generic '%' or a specific pattern that includes a '%d' (date) reference will now close the output file and open a new one if the system date changes while the program is running.

If the command from the second example above is started at 11:30pm (system time), the program will capture data for one hour but will produce two output files; one with the date and time it was started and another with the date and time that the program first outputs data after the system time passes midnight.