oscilloscope example developed

examples/redpitaya/Oscilloscope_example.m

+%% alter path to your python (3.8 is tested) distribution here
+py_path = 'C:\Users\Arthur-Vincent\AppData\Local\Programs\Python\Python38\python.exe';
+broker_ip = '127.0.0.1';
+
+
+%% Init components
+%oscilloscope properties --> delivering mqtt string for RedPitaya Inputs
+%mqtt stuff
+addpath('../../lib');
+addpath('../../lib/redpitaya');
+
+op = OscilloscopeProperties(); % get an object of the OscilloscopeProperties class
+
+% Two options to set sample rate
+op = op.set_sample_rate_by_div(1.01e-4); % Set time per Oszilloscope-Div
+%op.SampleRate = 15.6e6; % Set samplerate in MHz
+
+op.TriggerDelay =+8192; %Delay in samples (0 delay -> Start writing in the center of the buffer)     
+
+op.TriggerLevel = .001; % Trigger level in Volt
+
+test_message = op.get_mqtt_message();
+%test_message = '[OSC]\ntrigger_delay=100\ndecimation=1\ntrigger_level=0.2\ntrigger_ch=CH_1\ntrigger_src=CH_1_PE';
+
+myMqtt = mqtt_py_matlab(py_path);
+myMqtt.connect_mqtt(broker_ip);
+
+% Subscription to RP1 with wildcard (#)
+myMqtt.sub_mqtt_topics(broker_ip, "RP1/#");
+
+% Subscription without wildcard
+myMqtt.sub_mqtt_topics(broker_ip, "RP1/CONFIGURE/RECONFIG");
+
+myMqtt.sub_mqtt_topics(broker_ip, "RP1/raw/CH1");
+pause(2);
+
+% Publish Redpitaya API message
+myMqtt.pub_mqtt(broker_ip, "RP1/CONFIGURE/RECONFIG", test_message);
+
+% Read the last published message 
+fprintf('%s', myMqtt.get_payload_str("RP1/CONFIGURE/RECONFIG"));
+
+% get max length of x axis 
+x_axis = op.get_ordinate();
+
+pause(2);
+
+% Start oszilloscope
+myMqtt.pub_mqtt(broker_ip, "RP1/CONFIGURE/START", test_message);
+%% Filter
+
+Hd = fir_highpass2k;
+
+%% Signal aquisition
+
+%while(1)
+    % Read input 1
+    arr = myMqtt.get_payload_float("RP1/raw/CH1");
+    y_mat = cell2mat(cell(arr));
+    
+    %filter input 1
+    y_filt = filter(Hd,y_mat);
+    
+    % Plot input 1
+    subplot (2,1,1)
+    plot(x_axis, y_mat);
+    grid on;
+    
+    % Plot filtered input 1
+    subplot (2,1,2)
+    plot(x_axis, y_filt);
+    grid on;
+    
+    % Stop the aquisition
+    myMqtt.pub_mqtt(broker_ip, "RP1/CONFIGURE/RECONFIG", "STOP");
+%end
+

examples/redpitaya/fir_highpass2k.m

+function Hd = fir_highpass2k
+%FIR_HIGHPASS2K Returns a discrete-time filter object.
+
+% MATLAB Code
+% Generated by MATLAB(R) 9.8 and Signal Processing Toolbox 8.4.
+% Generated on: 15-Jun-2021 17:24:37
+
+% Equiripple Highpass filter designed using the FIRPM function.
+
+% All frequency values are in Hz.
+Fs = 2000;  % Sampling Frequency
+
+N     = 300;    % Order
+Fstop = 0.1;    % Stopband Frequency
+Fpass = 1;  % Passband Frequency
+Wstop = 1;     % Stopband Weight
+Wpass = 1;     % Passband Weight
+dens  = 20;    % Density Factor
+
+% Calculate the coefficients using the FIRPM function.
+b  = firpm(N, [0 Fstop Fpass Fs/2]/(Fs/2), [0 0 1 1], [Wstop Wpass], ...
+           {dens});
+Hd = dfilt.dffir(b);
+
+% [EOF]

examples/redpitaya/rp_read_with_matlab_example.m

+%% Define Red Pitaya as TCP/IP object
+clear all
+close all
+clc
+IP= '169.254.180.42';                % Input IP of your Red Pitaya...
+port = 5000;
+tcpipObj = tcpip(IP, port);
+tcpipObj.InputBufferSize = 16384*32;
+
+%% Open connection with your Red Pitaya
+
+fopen(tcpipObj);
+tcpipObj.Terminator = 'CR/LF';
+
+flushinput(tcpipObj);
+flushoutput(tcpipObj);
+
+% Set decimation vale (sampling rate) in respect to you
+% acquired signal frequency
+
+fprintf(tcpipObj,'ACQ:RST');
+fprintf(tcpipObj,'ACQ:DEC 8');
+fprintf(tcpipObj,'ACQ:TRIG:LEV 0');
+
+% there is an option to select coupling when using SIGNALlab 250-12
+% fprintf(tcpipObj,'ACQ:SOUR1:COUP AC'); % enables AC coupling on channel 1
+
+% by default LOW level gain is selected
+% fprintf(tcpipObj,'ACQ:SOUR1:GAIN LV'); % user can switch gain using this command
+
+
+% Set trigger delay to 0 samples
+% 0 samples delay set trigger to center of the buffer
+% Signal on your graph will have trigger in the center (symmetrical)
+% Samples from left to the center are samples before trigger
+% Samples from center to the right are samples after trigger
+
+fprintf(tcpipObj,'ACQ:TRIG:DLY 0');
+
+%% Start & Trigg
+% Trigger source setting must be after ACQ:START
+% Set trigger to source 1 positive edge
+
+fprintf(tcpipObj,'ACQ:START');
+% After acquisition is started some time delay is needed in order to acquire fresh samples in to buffer
+% Here we have used time delay of one second but you can calculate exact value taking in to account buffer
+% length and smaling rate
+pause(1)
+
+fprintf(tcpipObj,'ACQ:TRIG CH1_PE');
+% Wait for trigger
+% Until trigger is true wait with acquiring
+% Be aware of while loop if trigger is not achieved
+% Ctrl+C will stop code executing in Matlab
+
+while 1
+     trig_rsp=query(tcpipObj,'ACQ:TRIG:STAT?')
+
+     if strcmp('TD',trig_rsp(1:2))  % Read only TD
+
+     break
+
+     end
+ end
+
+
+% Read data from buffer
+signal_str=query(tcpipObj,'ACQ:SOUR1:DATA?');
+signal_str_2=query(tcpipObj,'ACQ:SOUR2:DATA?');
+
+% Convert values to numbers.% First character in string is “{“
+% and 2 latest are empty spaces and last is “}”.
+
+signal_num=str2num(signal_str(1,2:length(signal_str)-3));
+signal_num_2=str2num(signal_str_2(1,2:length(signal_str_2)-3));
+
+plot(signal_num)
+hold on
+plot(signal_num_2,'r')
+grid on
+ylabel('Voltage / V')
+xlabel('samples')
+
+fclose(tcpipObj)
\ No newline at end of file

examples/test_mqtt_py.m

@@ -8,6 +8,7 @@ myMqtt = mqtt_py_matlab(py_path);
 myMqtt.connect_mqtt(broker_ip);
 pause(1);
 
+%% sending and receiving a string value
 myMqtt.sub_mqtt_topics(broker_ip, "hello/test");
 myMqtt.pub_mqtt(broker_ip, "hello/test", "WORLD!");
 
@@ -15,6 +16,7 @@ pause(1);
 
 fprintf('%s', myMqtt.get_payload_str("hello/test"));
 
+%% sending and receiving a binary value
 signal = rand(1, 2000)';
 signal_b = typecast(single(signal), 'uint8');
 

lib/redpitaya/OscilloscopeProperties.m

+classdef OscilloscopeProperties
+    %OSCILLOSCOPEPROPERTIES Summary of this class goes here
+    %   Detailed explanation goes here
+    properties (Constant)
+        sample_rates = [125e6, 15.6e6, 1.953e6, 122.07e3, 15.258e3, 1.907e3];
+        rp_decimation = [1, 8, 64, 1024, 8192, 65536];
+    end
+    properties
+        SampleRate = 125e6;
+        TriggerDelay = 0;
+        TriggerLevel = .2;
+        TriggerCh = 'CH_1';
+        TriggerSrc = 'CH_1_PE';
+        Ch1Mode = 'DC';
+        Ch2Mode = 'DC';
+    end
+    
+    methods
+        function obj = OscilloscopeProperties()
+            %OSCILLOSCOPEPROPERTIES Construct an instance of this class
+        end
+        
+        function mqtt_message = get_mqtt_message(obj)
+            %METHOD1 Summary of this method goes here
+            %   Detailed explanation goes here
+            mqtt_message = ['[OSC]\n',...
+                'trigger_delay=', obj.get_trigger_delay_rp(),'\n',...
+                'decimation=', obj.get_decimation_rp(),'\n',...
+                'trigger_level=', num2str(obj.TriggerLevel),'\n',...
+                'trigger_ch=', obj.TriggerCh,'\n',...
+                'trigger_src=', obj.TriggerSrc,'\n',...
+                'ch1_mode=', obj.Ch1Mode,'\n',...
+                'ch2_mode=', obj.Ch2Mode];% obj.Property1 + inputArg;
+        end
+        
+        function rp_sample_rate = get_sample_rate_rp(obj)
+            [~, idx] = min(abs(obj.sample_rates - obj.SampleRate));
+            rp_sample_rate = obj.sample_rates(idx);
+        end
+        
+        
+        function rp_sample_time = get_sample_time_rp(obj)
+            rp_sample_time = 16384/obj.get_sample_rate_rp();
+        end
+        
+        function dec_rp = get_decimation_rp(obj)
+            idx = find(obj.sample_rates == obj.get_sample_rate_rp(), 1);
+            dec_rp = num2str(obj.rp_decimation(idx));
+        end
+        
+        function trg_del_rp = get_trigger_delay_rp(obj)
+            trg_del_smpl_num = obj.TriggerDelay*obj.SampleRate;
+            trg_del_smpl_num = max(-8191, min(8192, trg_del_smpl_num));
+            trg_del_rp = num2str(round(trg_del_smpl_num, 0));
+        end
+                
+        function obj = set_sample_rate_by_div(obj, time_per_div)
+            window_lengths = (8192*2+1)./(obj.sample_rates);
+            div_lengths = window_lengths/10;
+            [~, idx] = min(abs(div_lengths - time_per_div));
+            obj.SampleRate = obj.sample_rates(idx);
+        end
+        
+        function ordinate = get_ordinate(obj)
+            trg_del = double(string(obj.get_trigger_delay_rp()));
+            o_start = (-8191+trg_del)/obj.get_sample_rate_rp();
+            o_stop = (8192+trg_del)/obj.get_sample_rate_rp();
+            ordinate = o_start:1/obj.get_sample_rate_rp():o_stop;
+        end
+    end
+end
+