4. The code editor panel

The code editor is used mainly for writing and executing simple programs, i.e., for testing. These programs are sequences of the proprietary commands described in the Programming Manual. The robot’s command interface does not support conditionals, loops, or other flow control statements, nor variables. Comments are entered in C/C++ style (e.g., // and /* */).

For complex tasks, you must write a program outside the web interface (e.g., in your preferred integrated development environment) that parses the robot’s feedback, controls the robot, and handles all flow control logic. You can use any language that supports communication over TCP/IP (e.g., C/C++, C#, Python, Java or even Structured Text). Note that we offer a Python API on our GitHub account.

4.1. Using programs

You can create a new program using the button in the upper right corner of the panel. The program name can be changed and the program saved to the robot’s non-volatile memory by either double-clicking on the program tab or by clicking the icon at the bottom of the code editor panel, which is equivalent to pressing the shortcut Ctrl+Shift+s. You can also save the program directly using the shortcut Ctrl+s.

Programs can be saved in different folders. To specify a folder, and simultaneously create it if it does not exist, simply type the name of the folder followed by a slash, immediately before the name of the program. You can specify multiple layers of folders. Naturally, the program names in a given folder must be unique, as well as the sub-folder names in a given folder.

Program and folder names are case sensitive and must contain a maximum of 63 characters among the 62 alphanumerical (A..Z, a..z, 0..9), the underscore, the hyphen and the period.

A yellow dot to the right of the program’s name indicates that the program has been changed and needs to be saved. If a syntax error is found in the code, during the saving, the yellow dot will turn red, and a red will appear in front of each line of code containing a syntax error. Note that the syntax validation is performed by the robot (and not by the MecaPortal) when the program is saved. Local changes won’t be validated until the program is saved again.

The programs that appear in the code editor panel are simply those opened in the MecaPortal and not necessarily in the robot’s memory. The MecaPortal will locally save (in the browser’s local storage) the opened programs, whether or not they are saved on the robot. To open a program that is already in the robot’s memory, click on the icon. You can also delete programs from the same menu. Alternatively, you can delete a program that is opened and in focus, by clicking the icon. To simply close an open program, click the × on the tab with the program name.

A program can be called in another program with the StartProgram command, as in the following example:

StartProgram("my_folder/my_subfolder/program123")

To save and load programs from the robot, you must be connected to it in control mode, i.e., the connection state icon displayed in the menu bar must be .

You can also save the contents of the active code editor tab to your computer’s Downloads folder by clicking the icon. The file will be saved with the .mxprog extension. In addition, you can load a program from your computer, by clicking the icon.

4.2. Writing programs

The code editor provides syntax highlighting. In addition, once you start typing a command, a list of suggestions appears, allowing auto-completion. Furthermore, a brief description of the command appears, as shown in Figure 1. Additionally, pressing the secondary mouse button when your mouse cursor is over the code editor text field brings a context menu with all available commands (Figure 2). The most important group is in “TO CURRENT POSITION” which inserts the selected command at the text cursor with the arguments corresponding to the current robot position, the current tool reference frame (TRF), and the current world reference frame (WRF). To cancel the context menu without inserting a command, press Esc or click away.

Figure 2 Context menu in the code editor

The code editor includes various editing features for productive source code editing. The shortcuts for accessing these features are presented in Table 2. Note that you can select a block of text, a box of text (column select), or even have multiple cursors. Each line that has a text cursor or a selection of text becomes highlighted in gray and is called an active line. For example, in Figure 2, line 11 is an active line.

Table 2 Shortcuts for course code editing

Shortcut	Action
Ctrl+Space	Open the auto-complete popup menu
Ctrl+Shift+Space	Open the command help popup
Ctrl+a	Select all
Ctrl+d	Add selection to next find match
Ctrl+f	Open the find and replace dialog
Ctrl+g	Open the “go to line” dialog
Ctrl+/	Comment/uncomment active line(s)
Ctrl+Home	Move cursor to the beginning of the first line
Ctrl+End	Move cursor to the end of the last line
Ctrl+→	Move cursor to next group
Ctrl+←	Move cursor to previous group
Double click	Select group
Triple click	Select line
Alt+↑	Move active line(s) up
Alt+↓	Move active line(s) down
Shift+Alt+↑	Duplicate active line(s) and insert result above
Shift+Alt+↓	Duplicate active line(s) and insert result below
Alt + click & drag	Select a box of text (column select)
Ctrl + click	Place multiple cursors for simultaneous editing

4.3. Executing programs

You can execute the complete current program (even if it is not saved yet) by pressing the button at the bottom of the code editor panel. Alternatively, you can execute only the active line(s), by pressing the button, or by pressing Ctrl+Enter.

Once the robot starts executing motion commands, the button will become highlighted in yellow, and the green status bars in the menu panel will start blinking. You can press that button (or Alt+;) at any time to stop the robot and clear its motion queue (i.e., to send the ClearMotion command to the robot). Alternatively, you can press the button (or Alt+.) to pause the execution of motion commands (i.e., to send the PauseMotion command to the robot). To resume the execution of motion commands, press the button again (which sends the ResumeMotion command).

At any time, if a motion error occurs (either while the robot is executing a command or is idle), the button will become red. Pressing that button, or clicking the “Reset error” link in the red popup that will appear, acknowledges and resets the error (i.e., the MecaPortal sends the ResetError command to the robot). Once the error was reset, you need to ResumeMotion, by clicking the button (now blue).

Finally, recall that you can execute other programs, using the command StartProgram. With that command, you can only execute programs that have already been saved on the robot.