I am reading data from the a device using read(t) from ethernet.
Device continuously sending data over ethernet on some particular node.
I am reading this data continuously using while loop, giving while loop to some impossible condition to stop.
When I run my script I am not able to send any other command to device because while loop running continuously.
The program is not coming out of the while loop.
Is any way to read continuously data from Ethernet using tcpclient command.
Meanwhile, I am reading data from the device, how to send some commands to the device over ethernet using write(t,stop) command. because the script running continuously.
t = tcpclient("172.24.96.81",10952);
write(t,data1);
c=1;
while c~=1 % just to run while loop continuously
data2=read(t);
% manipulation from data2
end
t = tcpclient("172.24.96.81",10952);
Bytes_DATAF=t.NumBytesAvailable
configureCallback(t,"byte",Bytes_DATAF,#(varargin)readf1())
where readf1()
function readf1()
read(t)
end
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I am trying to write a pyserial command to the uart port to control the robot arm.
I have some manual:
manual for arm
manual command example
I use pyserial like that:
import serial
from time import sleep
port = serial.Serial("/dev/ttyUSB0", baudrate=9600, parity=serial.PARITY_NONE, stopbits=serial.STOPBITS_ONE, bytesize=8, timeout=1)
port.write(b"\x055\x55\x0B\x03\x02\x20\x03\x02\xB0\x04\x09\xFC\x03\xaa")
sleep(0.3)
#port.write(b"\x05")
#sleep(0.3)
#port.write(b"\x06")
#sleep(0.03)
#port.write(b"\x08\x01\x00")
print('send')
At first I tried to run it in one line, the buzzer will beep that the command was accepted, but the hand does not move.
Then I tried to split the Header separately for the Length in the next line and the Command with Parameters in the next.
Tell me how you can send these commands to the port, maybe there is something ready to do this in Python?
LSC Series Servo Controller Communication Protocol V1.2 manual says:
If the user transmits the correct data to the servo
controller, the blue LED 2 on the controller will flash one time, indicating that the
correct data have been received. If the user transmits the wrong data, then the blue
LED2 will not have any reaction and will keep the bright, then the buzzer will beepbeep twice to remind the user of the data error.
The only thing in that manual about that buzzer is that it beeps 2 times if there is a data error...
I am using matlab to communicate with several machines.
I am trying to connect with LCC25 (Liquid crystal retarder controller made by Thorlabs) using usb b to usb a cable.
I made a code like this.
clear all; clc;
%%
ss=serial('COM7','BaudRate',9600,'DataBits',8);
set(ss,'Parity','none');
set(ss,'Terminator','LF');
fopen(ss);
fprintf(ss,'*idn?');
aa=fscanf(ss)
fclose(ss)
Then I get "Warning : Unsuccessful read : A timeout occurred before the Terminator was reached aa=="
Is there any problem in my code?
I am also interested in buying the LCC25 and controlling it with MATLAB, so this is very interesting for me and I would love to find out whether it works...
To debug your code, I am wondering what happens when you comment out everything but:
ss=serial('COM7','BaudRate',9600,'DataBits',8);
set(ss,'Parity','none');
set(ss,'Terminator','LF');
fopen(ss);
Since then we can now if the problem is in establishing the connection itself (which you should not run every time btw!), or in trying to send a command to the device...
If the object creation is succesful, you should see something like this:
Serial Port Object : Serial-COM4
Communication Settings
Port: COM7
BaudRate: 9600
Terminator: 'LF'
Communication State
Status: closed
RecordStatus: off
Read/Write State
TransferStatus: idle
BytesAvailable: 0
ValuesReceived: 0
ValuesSent: 0
Then you can try to add run
fopen(ss)
fscanf(ss)
in a seperate file, and see what the output is. If all of this works, you can start to try sending commands using the 'fprintf' command, but make sure not to run the 'serial' and 'fopen' command every
I am wondering where you obtained the command string '*idn?', did you find this in the help file? The same for the terminator 'LF', are you sure this is the correct terminator to use for the LCC25? When reading the error message you received, I suspect the problem to be that you might need to use other terminators, such as 'CR'.
First I send data to Arduino from Matlab, then arduino proceed this data and send a message 'Ready' to Matlab to send him a new one. But this periodic communication is very slow.
This is my Matlab code :
for i =1:nbr
arduino_serial= serial('/dev/cu.wchusbserial1410');
set(arduino_serial,'BaudRate',9600);
set(arduino_serial,'Terminator','CR');
fopen(arduino_serial);
pause(1);
A_string = strcat(num2str(tabx(i)),',',num2str(taby(i)),',',num2str(pression_ref));
%Send
fprintf(arduino_serial,A_string);
%Receive from Arduino
while (strcmp('Ready',fscanf(arduino_serial,'%f'))==0)
end
fclose(arduino_serial);
delete (arduino_serial);
end
My setup in Arduino are :
Serial.begin(9600); // opens serial port, sets data rate to 9600 bps
Serial.setTimeout(100);
Is there another way to send periodic data?
Thanks
From your explanation, I think that your code is not apt. I have understood that Matlab waits for 'ready' from arduino, then it can send immediately the new message. Thus you dont have to close serial and reopen it each time; this part adds a delay of at least 1s!
You have to put opening and closing serial outside of your for loop.
For reliability you should increase sleep(1) to sleep(2).
Moreover there can be garbage in arduino serial buffer before you open it; if you encounter this, then you may read from arduino serial to empty the buffer (just after the sleep(2) instruction).
I have two laptops are connected via a USB cable, the USB on one end is attached to a USB to serial adapter. I need to send information from one laptop (Mac) to the other laptop (PC) through Matlab.
I know how to use fopen to use serial ports in Matlab to send these "markers" to the second laptop. However, I am unsure on how to read them at the receiving end.
I currently have the following code where the serial connection is opened:
% connect to serial port to send markers
portID = '/dev/tty.USA28X145P2.2';
global markerID
[markerID, err] = fopen(portID, 'w');
if ~isempty(err)
error('An error was returned whilst connecting to the serial port
to send markers. The error was:\n\t"%s"', err);
end
My Matlab script then calls a function that uses fwrite to write the information that I need to the object that was opened using fopen.
Now I am unsure how to "receive" these in Matlab on the other laptop. Do I need to use fscanf?
I am quite new to this so I'm not sure how to proceed. Any suggestions would be appreciated!
Thanks
I was using the simulink blocks 'serial configuration' and 'serial receive' to receive data from a Xbee module plugged into a serial comport. The Xbee module is supposed to send a string of data at 10Hz to the comport. As i run the program, simulink immediately crashes and shut down. The error message is EXCEPTION_ACCESS_VIOLATION . How could i possibly solve this?