TI-RSLK Module 1 - Lab video 1.4 - Running the TExaS oscilloscope
Introduction to embedded systems; code composer studio software installation and compile link download bug; TI-RSLK software installation, documentation and resources.
Resources
The overall purpose of this lab is to introduce the development tools needed to design the robot. For this lab, you're going to need your LaunchPad plugged into the PC. And you're also going to need to run TExaS Display. And this particular portion of the lab is to show you the debugging with an oscilloscope. Now, let's get started.
Now, if you have an actual oscilloscope, you should use it. However, if you do not have access to one, you can use the TExaS Oscilloscope. And in order to use it, we're going to connect a wire from P4.4, that's your oscilloscope, and we're going to attach it to something that we want to measure. So in this particular example, I'm going to attach it to P4.5. And so I'm going to be measuring the signal coming out of P4.5.
Now, over in Code Composer Studio, to run this example, I'm going to run TExaS. Now in TExaS, I've selected the oscilloscope main as my running. And you can see it's very simple here. What it does is just toggle the output P4.5. And that's the thing I'm going to measure.
Now, let me show you the modes here. Now, just like the logic analyzer, we have to initialize the oscilloscope. And over here in TExaS.h, you can see all the different ways we could have initialized it. In the last video, we used a logic analyzer on port 1. And in this one, we're going to set it up to be an oscilloscope, to choose scope.
All right, now let's run. All right, so to build it, I click on the project that I want to run. See, now that's active. And I go build. And that compiles it. And when I hit the Debug button, it downloads, and then we'll launch the debugger.
And just like the logic analyzer, in order to use this device, it has to be running. Now, in the background along with your program, 10,000 times per second, the analog to digital converter on P4.4 is sampled. And that analog signal is passed up to the PC for plotting.
All right, let's go over to TExaS Display. All right, so in TExaS Display, we've got to connect up to the com port. And now we're going to select oscilloscope as my option. And we see here it's measuring that waveform.
So what an oscilloscope is, is on the y-axis here, it's measuring voltage. Now, this is only 0 to 3.3 volts and it is sampled 10,000 times a second. And what's plotted here is voltage versus time.
We have some options here. We can zoom out in time here. We can zoom and make it go slower so we can see more of the wave, or we can zoom in and see less of the wave. In this lab, you learned how to use an oscilloscope to measure voltage versus time. Observing input-output is an important task needed to design a robot. Have fun.