function keypad (action) %callback function for the GUI
persistent binaryout;
switch(action)%switch through each button
    case('Start')
        %define the header lines
        dio=digitalio('mcc', 1);
        %output line
        addline(dio, 0:3,2,'Out');
        %input lines
        addline(dio, 0:2, 0, 'In');
        addline(dio, 4:7, 0, 'In');
        addline(dio, 1, 3, 'In');
        %initialize
        b_Start = findobj('Tag', 'btnStart');
        set(b_Start, 'UserData', 1);
        h_bin_out = findobj('Tag', 'Bin_Data_Out');
        %grab the Binary Data Recieved Box
        t_In = findobj('Tag', 'txtReceived');




        while(get(b_Start, 'UserData') == 1)
            putvalue(dio.Line(1:4), binaryout);

            %see if the dio needs to be reconfigured
            flow = dio.Line(12).Direction;
            if (isequal(binaryout,[0 1 0 1]) && strcmp(flow, 'Out'))
                reconfigure(dio, '0'); %reconfigure for input
            elseif (isequal(binaryout,[1 1 0 0]) && strcmp(flow, 'In'))
                display('here');
                reconfigure(dio, '1'); %reconfigure for output
            end
            %grab the input value
            %in_value1 = getvalue(dio.Line(5:12));
            % if (isequal(binaryout,[0 1 0 1]))
            %convert the vector to string
            % in_value = flip(transpose(dec2hex(in_value1)));
            % else
            %convert the vector to string
            %in_value = transpose(dec2hex(in_value1));
            %end
            %update the output textfield
            %set(t_In, 'String', in_value);
            %update the output textfield
            %set(t_In, 'String', in_value);
            if(isequal(binaryout,[0 1 0 1]))
                received = getvalue(dio.Line(5:12));
                in_value = flip(transpose(dec2hex(received)));
                %binary_rec = dec2bin(binvec2dec(received), 4);
                set(t_In, 'String', in_value);
            elseif (isequal(binaryout,[1 1 0 0]))
                bstr_out = get(h_bin_out, 'String');
                dec_out = bin2dec(bstr_out);
                bv_out = dec2binvec(dec_out, 8);
                putvalue(dio.Line(5:12), (bv_out));
            end
            drawnow;
        end
    case('Stop')
        %set start to zero
        b_Start = findobj('Tag', 'btnStart');
        set(b_Start, 'UserData', 0);
    case('Slide')
        % Find the handles
        h_sld = findobj('Tag','Slidey');
        h_bin_out = findobj('Tag','Bin_Data_Out');
        % Get slider's value
        sld_val = get(h_sld,'Value');
        % Convert to binary, 8 bits
        sld_bin = dec2bin(sld_val,8);
        % Update text box
        set(h_bin_out,'String',sld_bin);
    case('0')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 0;
        binary = '0000';
        binaryout = [0 0 0 0];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('1')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 1;
        binary = '0001';
        binaryout = [0 0 0 1];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('2')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 2;
        binary = '0010';
        binaryout = [0 0 1 0];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('3')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 3;
        binary = '0011';
        binaryout = [0 0 1 1];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('4')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 4;
        binary = '0100';
        binaryout = [0 1 0 0];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('5')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 5;
        binary = '0101';
        binaryout = [0 1 0 1];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('6')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 6;
        binary = '0110';
        binaryout = [0 1 1 0];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('7')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 7;
        binary = '0111';
        binaryout = [0 1 1 1];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('8')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 8;
        binary = '1000';
        binaryout = [1 0 0 0];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('9')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 9;
        binary = '1001';
        binaryout = [1 0 0 1];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('A')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 'A';
        binary = '1010';
        binaryout = [1 0 1 0];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('B')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 'B';
        binary = '1011';
        binaryout = [1 0 1 1];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('C')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 'C';
        binary = '1100';
        binaryout = [1 1 0 0];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('D')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 'D';
        binary = '1101';
        binaryout = [1 1 0 1];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('E')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 'E';
        binary = '1110';
        binaryout = [1 1 1 0];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
    case('F')
        %grab the binary textbox and the hex textbox
        t_hex = findobj('Tag', 'txtHex');
        t_binary = findobj('Tag', 'txtBinary');
        %value of hex.  value of binary
        hex = 'F';
        binary = '1111';
        binaryout = [1 1 1 1];
        %set the value of hex
        set(t_hex, 'String', hex);
        %set the value for binary
        set(t_binary, 'String', binary);
end
return



%=========================================

function [] = reconfigure( hw_object, mode )
    %display('here!');
    %putvalue(hw_object.Line(5:12), 0); %put an erroneous address out
    stop (hw_object);
    delete(hw_object.Line(5:12)); %delete the bidirectional bus lines
    if strcmp (mode, '1')%desired mode is output
        addline(hw_object, 0:2, 0, 'Out'); %assign lines
        addline(hw_object, 4:7, 0, 'Out');
        addline(hw_object, 1, 3, 'Out');
    elseif strcmp (mode, '0')
        addline(hw_object, 0:2, 0, 'In'); %assign lines
        addline(hw_object, 4:7, 0, 'In');
        addline(hw_object, 1, 3, 'In');
    end
    start (hw_object);
end