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I am currently working on a senior design project. I have always been a software person, but it seems that this project requires quite a bit of hardware knowledge. We are trying to measure respiratory rate using respiratory inductive plethysmography. My supervisor told me that I am going to need an EVM/eval board, but I have never used one, and the existing information online is confusing. Does anyone have any recommendations for what types of EVM boards we could use, or just a good place to find more general information about them?

Nathan
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  • You use the evaluation board for whichever chip or module or product is actualy useful in your design. – The Photon Dec 04 '19 at 03:23
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    An evaluation/development board is just a convenient method of creating a breadboard of a system without a lot of custom hardware design. You need to start with your requirements, two of the most important are I/O and processing capability. Analog inputs? Sampling rate? Keyboard? Push-buttons? Built-in LCD display? HDMI port to an external monitor? etc. Then you can start narrowing it down. There are hundreds of options. – Mattman944 Dec 04 '19 at 03:32
  • Are you talking about eulerian video magnification from MIT? (If so, you should just say so.) – jonk Dec 04 '19 at 03:34
  • You first select the processor you think you are going to need, then you check if there is an evaluation board available for it. You normally select the processor on the basis of what I/O functionality you need and what CPU power and memory amount you think you need. – Oldfart Dec 04 '19 at 04:20
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    Evaluation board for what? A MCU? Some other part? – Lundin Dec 04 '19 at 07:58
  • Your supervisor probably had a particular chip in mind. Ask. – Scott Seidman Dec 04 '19 at 12:32
  • You're working on an algorithm for Respiratory Inductive Plethysmography (RIP) and your Supervisor wants you to get an EVAL board like an ADC/DAQ that will do nothing more than cause problems and delays. So my answer to get the right hardware is a better solution and explaining your why your question is irrelevant will not help . So -5 and @Dave T deleted it.doh! Good luck. But if you need to learn the Murphy's Laws of hardware development .. do it – Tony Stewart EE75 Dec 04 '19 at 17:15

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I use the evaluation board whenever I: (Some applies with or without programmable devices).

  • When I have a fairly big/complex design that I'm not used to, especially when it does have a complex software stack. It gives a starting point when you have something "that works". From there, you modify the software to do what you need, step by step. Later on, you move to your own board design and can rely on your eval board as a reference point to solve problems as it gives you a reference to check signals, software stack, etc...

  • When I have to make a project quickly, as it takes time to manufacture PCBs, you can already build most of your software before you get the board.

  • Testing the capability of a specific chip.

  • Build prototypes, save time and money. Using several eval boards (or breakout board) you can often build a whole circuit before starting to design a PCB, giving you the best chance to have it working at first shot.

Side story, a company I used to work for one day decided to stop prototyping electronics and just send them directly to manufacture. It was a bad decision and they wasted a massive amount of time and money.

In your case, you will probably get an eval board of the sensor you decided to use, if it doesn't exist then solder it to some breakout board, choose some demo MCU board like Arduino, STM32 or PIC and wire them together and end up with something looking like this:

enter image description here

Damien
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An evaluation board is (generally) a basic system built around some specific part, along with all the other stuff you need to get that part to work. Sometimes you'll find one built around a technique, rather than a part. (Maybe there is a "respiratory inductive plethysmography evaluation board", but I doubt it.)

For example, an evaluation board for a CPU would typically have that CPU, some RAM, an SD card slot so you can insert your code, some USB ports, some PCI Express slots, an Ethernet port, a header for GPIO/I2C/SPI pins, and perhaps also a VGA port.

Imagine a Raspberry Pi. A Raspberry Pi could be an evaluation board for the CPU that is on the Raspberry Pi (the BCM2837 chip). If you wanted to use a BCM2837 as the CPU in your product, you could prototype your device by using a Raspberry Pi. Maybe your product has some sensors, which you wire up to the GPIO pins on the Pi. Maybe it needs to run on batteries, so you grab a USB power bank from a store and plug the Pi into that.

(I'm using the BCM2837 as an example. As far as I know, these chips are only intended to be used in Raspberry Pis. But you can imagine the same thing with any other chip)

Once you stick all these pieces together, and write the software, and it works, you can produce your own circuit board with all the chips on it, and all the connections, because customers won't buy a pile of separate circuit boards and doo-dads duct-taped together. Your circuit board would have the CPU, memory, power supply, sensors, and everything else, on the one board. And then you can connect a battery to it (just a battery, not a USB power bank, because all the other circuitry is on your circuit board), put it inside a neat plastic case and sell it to people.

It sounds like for your project you just want a prototype, so you won't need to design everything onto one circuit board. I'm telling you so that you get some perspective on why evaluation boards exist.

And evaluation boards are all different, depending on what they're designed to help you evaluate. Asking "which evaluation board can I use?" is a bit like asking "which circuit board should I use?". Don't look directly for evaluation boards - look for a part you want to have, then look for evaluation boards which have that part or a similar one. Often the part is simple enough that you don't need an evaluation board, so don't get hung up on evaluation boards either. It might be useful to collaborate with someone who has some hardware design experience.

user253751
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