以讀取 A/D 為基礎的快速原型設計功能
讀取類比訊號的數位值,是另一項基本電氣工程功能。 因此這項簡易的操作無需編程即可完成。
此模組提供以讀取類比轉數位轉換器 (ADC) 為基礎的逐步原型設計功能(含示範)
資源
OK. So some of you are probably saying, seriously, he just did a demo of a square wave? Too simple. But hold on. Give me a minute here. We'll revisit the concept in a few slides.
So now, let's continue on with our step by step functionality. And look at our next prototyping function. Reading the A/D. Who doesn't need to read an A/D at some point, whether it's some type of temp sensor or reading the microphone, my voice or a certain voltage.
Looking at the pin map of the TI LaunchPad, we'll see that we do have analog inputs marked, in this case, A3. Happens to be actually GPIO pin 1.3, but is also multiplex. There's an analog input. And we can apply voltages to it.
I guess it could have brought in the bench supply and done different voltages. But conveniently, VCC is pinned down on this LaunchPad as is ground. And we'll just use that for the demo.
So going to the block diagram of the demo, once again, we have a LaunchPad that USB bus powered. And we'll also have an A/D coming in from the high and low voltage that we mentioned. You can see three volts high and zero volts low. And the voltage will be reflected on a putty screen.
OK. For the A/D demo we have the LaunchPad, again, USB bus powered. And as mentioned, we have pin 1.3, which can be GPIO, but in this case has been changed to analog input three. In to that pin we have a scope rope connected, and also a white wire that is then connected to a nicely labeled ground coming from the ground that's on the LaunchPad itself.
Well at the the scope, we have showing the signal at ground. And if you look at the putty window, you can see that it's reporting zero. I can then very easily, as we mentioned, BCC on the board connected to a clearly marked red wire and clip. Can unclip the ground from A3 pin, and now connect VCC to A3. And you clearly see the scope going up to three volts, as does the putty window.
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快速原型設計 – 從我們的解決方案上手
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