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Scilab Read Serial: Examples and Tips for Using Serial Communication in Scilab



So it is possible to print the capacitive sensor value in the serial port terminal and read it immediately with SciLAB in order to convert the string in SciLAB in float and store the value in a vector for plot it.




Scilab Read Serial




Values of capacitive sensor are printed every 100ms in the serial port terminal and whatever the way they are printed (524545 or 45 56 65 or 45,87,98,120), this is a difficult work to extract the correct string of the monitor.


First of all Aditya Sengupta hasn't updated his repository for the last 8 years and there have been already a lot of issues reported everywhere. Unfortunately the pull requests and issue reports have also been around for a long time. So I decided to fork the repo with many improvements here:


but to answer your question, you can write your information in CSV format into the serial port and then use the csvTextScan to convert them into matrix. I have explained everything here in details. and a demonstration can also be found here with instructions:


When you want to get data from an instrument, and process itin Scilab, just capture data to a file with Realterm, then haveScilab read the file. This is a "design pattern" thatappears ugly, but has been easy to get going, and sucessful. Itis well decoupled, which is what makes it so easy to do.


The Verbose input is set to %f by default returning a vector ofstrings. If set to %t it will export a matrix including more elaboratedetails about the specified PortList. The PortList option can be"all" for showing the valid ports available or open, "available" forshowing the ports are free to be opened, "open" for all the alreadyopened ports and "defined" for showing all the ports which are alreadydefined.


it is not recommended at all, and should be avoided at all costs. youmay always redefine the objects setting the OverWrite input to %twith the new properties. Otherwise, reading the information through the. operator is fine.


The SerialPort input must be a defined serial port object defined byserial function otherwise it will return %f for Result. The listof defined serial objects can be found using theslist(PortList = "defined") command. The Access input can beset to "r", "r+", "w", "w+", "a", "a+". The function willmake sure the specified port is a valid, defined and available serialport. If the Reopen input has been set to %t the function will closeit and reestablish the connection.


In this example (inspired bythistutorial) you will learn how to communicate with an Arduinomicrocontroller (MCU) expansion board and a Windows PC, through serialport. By the end of this example you will be able to read the value of apotentiometer, while this can be also expanded to reading any other sensorsas well. To follow along the example you require the hardwareincluding an Arduino Uno MCU development board, a potentiometer, wiringand breadboard.


buffer: is like a container on the on both sides of thecommunication ports. The sender stores the data there before flushingthem through the port and the receiver stores them there before dumpingthem over to the users space. The buffers have limited size which ifexceeds the oldest data will be discarded. The size of buffer can be setthrough InputBufferSize and OutputBufferSize serial object property,which can not exceed the maximum provided by the hardwareMaxInputBufferSize and MaxOutputBufferSize. If you do not flush/readthe data on the sender/receiver side in time it can lead to irreversibledata loss.


polling and streaming: when requesting one single measurementsfrom a sensor, it is called polling. If we read data from the sensorgiven a certain frequency it is called streaming.


Serial Command Interface (SCI): firstly used by Motorola in the1970s, is basically a language known by the serial device (e.g. MCU) todo certain things upon receiving certain messages.


In my previous tutorial here in this blog,I showed how to read temperature with a purpose written app in App Inventor for Android phone that connects to BBC micro:bit through Bluetooth Low Energy (BLE). With an edge connector more pins can be accessed facilitating connection to other devices. Despite BBC micro:bit having hardware capable of allowing the device to work as a BLE device, it has disadvantage that only has 16k of RAM. The BLE stack alone takes up 12k RAM which means there is little room to run MicroPython and bigger codes.


Connect BBC micro:bit to Scilab for reading anf plotting temperature of the processor on micro:bit. Write the codes, using the simplest ways, for the BBC micro:bit and Scilab, and test the setup.


Windows 10 & 8.1: Windows Update will fetch any necessary drivers. For earlier versions of Windows, (Windows 7, or Vista) if you would like to use serial communication (not necessary to program your micro:bit) you will also need the Arm MBED serial port driver.


We will use Serial communication with Scilab. Before we can use the micro:bit serial port, we need to install a serial terminal program, and we also need to install the USB serial driver. In this tutorial, we will be using Tera Term. To get the driver, start by following the links below, then follow the installation instructions.


You are now ready to install the firmware on BBC micro:bit which behaves like a drive in your PC and will be visible. You will need to copy, or drag and drop, the hex file into BBC micro:bit:


The plot shows variation of temperature by blowing air with mouth, over the processor. If we click onto Stop measuring, Scilab will stop reading the temperature and the plot will stop.


since when I've started playing with Arduino, I have always been wandering how I could make it talk and interact with the Matlab environment in an easy and effective way. I bumped into many Instructables and tutorials dealing with Arduino libraries and Matlab script files to get them talking one to each other. What I've never been able to find, though, was a straightforward tutorial that could teach me how to understand the core of the serial communication with an external hardware.


I'll be go through few steps in which I'll be illustrating the basis of a serial communication established between Arduino (our external physical interface) and our PC (the data collector and elaborator). Everything will be referred to a very simple case study of a temperature/humidity sensor (DHT_22) wired up to Arduino, and that will act as the data source. The fun thing is that this Instructable applies quite unchanged to almost all tipe of sensors you want to get and visualize data from! So temperature, humidity as well as light, proximity sensors or 3-axis gyroscopes....The core is really the same!


The general idea one should keep in mind when it comes to wire up Arduino to Matlab is that they shall communicate using the same language and protocol. That is the serial communication via USB port. Both In Arduino and Matlab coding environment we have specific commands that enables the serial communication, but the core behind its operation is built on the same few principles:


What we are going to do, after wiring up the temperature sensor as illustrated in the Fritzing scheme, is writing the code that will run on Arduino, and a Matlab script with a bunch of functions, that will allow us to query Arduino for the temperature readings.


Before illustrating the codes in detail, let's fix the concept by schematizing the whole thing:on the Arduino board we will upload a program that, when asked by a serial command (serial means that passes through the serial port!), will make the board retrieve the temperature reading from the sensor, and subsequently copy it in the serial buffer, ready to be picked up by Matlab! Matlab, on the other side, will do the rest of the job: a script will be run, and at a fixed frequency, will send the Temperature reading request string to Arduino, and will read back the temperature value sent to the serial buffer plotting it in a real time graph Temperature vs Time.


Attached here, you will find the .ino file with the script you will have to upload on your board, but since I said that this want to be a tutorial whose main aim is to lead you directly to the core of the versatile serial communication between Arduino and Matlab, let me comment it! (you may want to open the .ino file in the Arduino IDE and follow the following comments in parallel, trust me it will help you). I really don't like to fill the script itself with comments, since it result in a messy look!Skip the following lines if you are using a different sensor, or your purpose for using the serial communication with Matlab is different! The script start with the inclusion of the DHT library you will find attached as well (copy the .cpp and .h files in a folder called DHTlib inside the libraries folder related to Arduino in your PC, you aren't going to need anything else) and defining a couple of useful variables: temp, to store the temperature value, and val, assigned to the characters sent by Matlab.In the setup area we have to include the real player of the game: serial communication initializer. more info here>> Arduino Serial. So we write Serial.begin(9600), where 9600 is the baud rate, namely the velocity at which we would like the two guys to talk to each other (we will set the same rate when we will take care of the Matlab serial object). The few code lines that follow are just a simple handshake to know if the serial communication has started flawlessly. Actually you can exclude it! Just not to leave anything unclear, with the handshake, Arduino send the character 'a' to the serial buffer, and when Matlab will read it visualizing an "ok message" we will know that they are talking to each other properly.Now let's come to the main loop. Arduino always has to keep an eye wide open on what it's happening in the serial port! So with the line 2ff7e9595c


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