simple_stream.m

% this is a simple gcode sender for matlab
% Samuel Freitas 5/31/2022
warning('off','serialport:serialport:ReadlineWarning');

clear all
close all force hidden

GRBL_com_port = "COM3";
gcode_path = "grbl_test.gcode";
BAUD_RATE = 115200;

gcode = importdata(gcode_path);
gcode_string = string(gcode);

ser = serialport(GRBL_com_port,BAUD_RATE);
ser.Timeout = 0.1;

send_wake_up(ser)

for i = 1:length(gcode_string)
    
    this_string = gcode_string(i);
    cleaned_line = char(remove_eol_chars(remove_comment(this_string)));
    
    if ~(isempty(cleaned_line))
        
        disp(string(cleaned_line))
        
        writeline(ser,cleaned_line);
        wait_for_movement_completion(ser,cleaned_line);
    end
end


function out = remove_comment(this_string)
comment_idx = find(char(this_string) == ';', 1);
if isempty(comment_idx)
    out = this_string;
else
    temp = char(this_string);
    out = string(temp(1:comment_idx-1));
end
end

function send_wake_up(ser)
%     # Wake up
%     # Hit enter a few times to wake the Printrbot
writeline(ser, char("\r\n\r\n"))
pause(2)  % Wait for Printrbot to initialize
flush(ser,"input")  % Flush startup text in serial input

end

function out = encode_string(in_string)
% found that you just need to send chars to the GRBL controller as a line
out = double(char(in_string));
end

function out = decode_unicode(in_unicode)
out = string(char(in_unicode));
end

function out = remove_eol_chars(in_string)
out = strip(in_string);
end

function wait_for_movement_completion(ser,cleaned_line)

pause(1)

if ~isequal(cleaned_line,'$X') && ~isequal(cleaned_line,'$$')
    
    idle_counter = 0;
    
    while 1
        
        %             # Event().wait(0.01)
        flush(ser,"input")
        command = char(['?\n']);
        writeline(ser,command)
        grbl_out = readline(ser);
        grbl_response = decode_unicode(strip(grbl_out));
        
        if ~isequal(grbl_response,'ok')
            
            if contains(grbl_response,'Idle')
                idle_counter = idle_counter + 1;
            end
        end
        
        if idle_counter > 10
            break
        end

        pause(0.2) % in the GRBL documentation it reccomends a 5Hz rate for the '?' command

    end
    
end

end

function send_grbl_command(ser,command)

this_string = command;
cleaned_line = char(remove_eol_chars(remove_comment(this_string)));

if ~(isempty(cleaned_line))
    writeline(ser,cleaned_line);
    wait_for_movement_completion(ser,cleaned_line);
    
    disp(this_string);
end

end

function read_grbl_output(ser)

out = readline(ser);
for i = 1:100
    out = readline(ser);
    if isempty(out)
        break
    else
        disp(out)
    end
end

end

function send_grbl_command_read_output(ser,command)
send_grbl_command(ser,command)
read_grbl_output(ser)
end

function ser = easy_grbl_setup(GRBL_com_port,BAUD_RATE)

ser = serialport(GRBL_com_port,BAUD_RATE);
ser.Timeout = 0.1;

send_wake_up(ser)

end