As noted by jwpat7 the port can be accessed by one application at a time, so when the serial monitor is open no other application can access it. The hang might happen because when first connecting to an arduino port the arduino gets reset and waits for a second or so for programming data (that's how a new sketch is updated). I don't know for sure, but this might mess up with cat and make it to hang up. Best option might be to make a script like jwpat7's that would wait a second after opening the port and then send the file contents in.
To make a long story short: I need to read data from a text file, which will then be displayed on a (serial) LCD. Part of a much larger. Arduino Serial Data Acquisition. What if you use Arduino Uno? -This File Exchange download will help you do. Run this script to read and plot serial data in. Tutorial: passare valori dal PC ad Arduino per via seriale Tutorial - sending values from PC to Arduino by serial communication. I am trying to read a text file 'Print1.txt', line by line, from an SD card attached to my Arduino MEGA. So far I have the following code: #include #include.
Ah, Arduino, I remember when you were just crawling around and blinking LEDs. Now you're ready to learn how to speak! In this lesson we'll learn how to use the Serial Library to communicate from the Arduino board back to the computer over the USB port. Then we'll learn how to manipulate numbers and data. For this lesson we won't be using the shield, so simply remove it (keeping the mood light LEDs on it you'd like).
The shield doesn't contain any programs or data, it is just our way of connecing up the LEDs and resistors. We'll use the shield again but for now, we can examine the RX and TX LEDs on the main Arduino board which will help you with debugging.
Libraries are great places, and not yet illegal in the United States! If you ever need to learn how to do something, like say fix a motorcycle, you can go to your local library and take out a book. Sure you could buy the book but the library is nice because as a resource you can get the book whenever you need it, keeping your house uncluttered. Software Libraries are very similar. We already studied what a procedure is, in: a procedure is a list of things to do. A library is a big collection of procedures, where all the procedures are related!
If you, say, want to control a motor, you may want to find a Motor Control Library: a collection of procedures that have already been written for you that you can use without having to do the dirty work of learning the nuances of motors. Download Rotor Gene 6000 Software Engineering. The library we will be using is the Serial Library, which allows the Arduino to send data back to the computer. Serial may sound like a tasty breakfast food, but its actually quite different. The word serial means 'one after the other.' For example, a serial killer doesn't stop with one murder, but stabs many people one after the other. Serial data transfer is when we transfer data one bit at a time, one right after the other. Information is passed back & forth between the computer and Arduino by, essentially, setting a pin high or low.