LabVIEW
How to send joystick data over TCP connection
@Physicsnole wrote:
In the attached VI I am trying to send data from a joystick over a TCP connection. I can send data fine using the TCP examples (in fact the majority of my VI is just a copy of the example). However I am to the point where I do not know how to send all the data necessary (3 axis data, 12 buttons, and the POV data) over TCP. Strings, clusters, and arrays were never my strong suite and converting between them is a nightmare for me.
Well, you cast the axis info cluster to a string, but then you cast it back to an array of DBL. Thatr's not compatible. You should probably cast it back to an "axis info" cluster of exactly the same type. Go the the other VI and right-click the cluster wire to create a constant. Now move that diagram cluster constant to the other VI and use it as type.
Your default ports don't seem to match. You seem to have client and server roles confused. In the sever you create a listener, but then you start sending packets, even though no connection is established. The connection needs to be initiated by the client.
Your client stops the loop the first time a timeout is encountered. Shouldn't that be more permanent? Also, please retain code clarity and avoid unecessary complexities. For example, replace the "not or" with a plain "or" and change the loop to "stop if true"
Physicsnole wrote:Basically I am trying to send each axis data (X,Y, and Z), button data (12 buttons), and POV data (the POV data will be calculated to adjust the position of a camera, so the immediate data is not important, I will add functions to add the change in the button movements to write a standing position for two servos [pan and tilt], for which that I will need to send over the TCP connection) over the TCP connection to control various cameras and motors. I don't know if it is posible to send that much data over a TCP connection in one write VI through a string, and also how to separate the string on the other side in order to control the client VI.
You can send as much as you want. The casting to/from string is the same as described above.
Physicsnole wrote:Another question I have (not impotant to get the program running just might make it easier on me) is can a TCP server (which sends the data to the client) also recieve data back from the client on the same port ( for example sensor data and digital positions [on,off])? Or do I need to set up two TCP communication loops with the first client acting as the server on a different port than the first, which then sends the data to the original server, which also has a client TCP configuration in another loop? I hope this makes sense..
The primary function of a "server" is to wait for a connection and then communicate with the client once a conenction is established. An established TCP/IP connection is fully two-way and both sides can send and receive.
