classdef DC_supply
    % Simple control of DC supply via fixed GBIB address.
    % Agilent E3646A

    properties(Access=public)
        active
        voltage
    end

    methods (Access=public)

        function obj = DC_supply(options)
            

            arguments
                options.active bool = true
                options.voltage double = [0,0];
            end

            %
            fn = fieldnames(options);
            for n = 1:numel(fn)
                try
                    obj.(fn{n}) = options.(fn{n});
                end
            end

            assert(size(obj.voltage,1)==1,'Set Voltage for CH1 and CH2 must be given as vector [V1, V2]');
            assert(size(obj.voltage,2)==2,'Set Voltage for CH1 and CH2 must be given as vector [V1, V2]');

        end

        function success = set(obj)

            success = false;

            try
                %connect to device
                v = visadev("GPIB0::19::INSTR");
                % fopen(v);

                writeline(v, '*IDN?;');
                disp(['DC Source: ' readline(v)]);

                cmd = 'INST:SEL?';
                fprintf(v, cmd);
                selected_channel = fscanf(v);

                for ch = 1:2

                    % choose channel
                    cmd = ['INST:SEL OUT',num2str(ch)];
                    fprintf(v, cmd);

                    % get current voltage level
                    cmd = ['VOLT?'];
                    fprintf(v, cmd);
                    act_volt = str2num(fscanf(v));

                    % desired voltage (round to two digits after comma)
                    des_volt = round(obj.voltage(ch),2);

                    cnt = 0;
                    while abs(act_volt-des_volt) > 0

                        selected_channel = ['OUT',num2str(ch)];

                        % get current voltage level
                        cmd = ['VOLT?'];
                        fprintf(v, cmd);
                        act_volt = str2num(fscanf(v));

                        % difference
                        diff_volt = act_volt-des_volt;

                        % set new voltage
                        increment_voltage = -0.01* sign(diff_volt) ;
                        cmd = ['VOLT ',num2str(act_volt+increment_voltage)];
                        fprintf(v, cmd);

                        cnt = cnt+1;
                        if mod(cnt,100) == 0
                            wait(1);
                        end

                        % get current voltage level
                        cmd = ['VOLT?'];
                        fprintf(v, cmd);
                        act_volt = str2num(fscanf(v));

                    end

                    % check if voltage is set
                    if act_volt ~= des_volt
                        hMsgBox = msgbox('An error occurred in dc supply module. Check if voltage is set correctly.');
                        uiwait(hMsgBox);
                    end

                end

                % choose channel
                cmd = ['INST:SEL ',selected_channel];
                fprintf(v, cmd);

                %disconnect
                fclose(v);
                delete(v);

            catch


            end


        end

    end

    methods (Access=private)



    end
end