Serial plotter remote commands

[chromhelm]

This adds remote command to set the size and clear the plot area. The commands are send like this: #CLEAR #SIZE: size should be between 10 and 5000. This are hard coded limits for the plot size right now.

[madsdyd]

Is there a consensus about adding "remote commands" (this patch include them)", vs. e.g. the ability to be able to ignore some lines? Traditionally, "#" is often used to indicate a comment in text based data files. An initial suggestion could be to expand the SerialPlotter protocol to

• Ignore any line starting with "#"
• Interprent any line starting with "$" as a command to the serial plotter.

The reason for "$" being that it is often used indicate a command prompt.

[madsdyd]

Status of the QA check is that it fails because

• The method setNewBufferCapacity assigns to one of its parameters.
• Line 326 needs to be changed from if (commands.equals("CLEAR")) { to if ("CLEAR".equals(commands)) {

Both are trivial to fix

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:x: Wilhelm Wiens

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[stefan123t]

Thanks for adding the Serial Plotter with Labels and Commands to the Arduino IDE!

• I am trying to find the Serial Plotter protocol documentation time and again. Here is PDF documentation by @chromhelm and here are the official markdown docs as well as a suggestion by @per1234 to enhance / update existing examples with labels

Regarding remote commands and comments as described in this PR:

Is there a consensus about adding "remote commands" (this patch include them)", vs. e.g. the ability to be able to ignore some lines? Traditionally, "#" is often used to indicate a comment in text based data files. An initial suggestion could be to expand the SerialPlotter protocol to

* Ignore any line starting with "#"

• I agree that # is almost ubiquitious for comments along with optional // line comments and /* */ multiline comments.

• The command line should be part of a comment, e.g. something like a shebang: # $ CLEAR; or #% $ SIZE 5000,500;

• There are feature requests to ignore lines arduino/arduino-serial-plotter-webapp#28 and adding a filter / regex for plotting only specific interesting lines arduino/arduino-serial-plotter-webapp#21 .