Hi,
We are looking for ways to use Jetson’s GPIO pins in realtime accuracy.
Is this any way to do so through L4T OS?
We’ll be happy to hear your suggestions.
Thanks
Just an opinion, but GPIO is quite difficult to use in “realtime”. However, there is a huge difference if you are considering something at say a 1KHz rate versus 100Khz versus many MHz or GHz. If you are working slow enough, then you can use GPIO as “realtime”. If you are using any significant speed, then I’d say you probably want external hardware added on.
Are there tutorials on how this can be done. we want to collect real-time data from multiple electronic devices.
So far as I know there is no such tutorial for a Jetson. Usually such information is found for a specific hardware designed for data collection, e.g., you might have a hardware module designed specifically for A/D or D/A sampling, and the information would apply to that specific hardware.
I have not done it (I can’t offer any practical advice on where to start with this), but there are people who have used the image signal processor (“ISP”) for other purposes when there is no camera. Or the audio processing engine (“APE”) for other purposes than audio when no audio is used. Those engines are ARM Cortex-R5 processors, and are designed for real time function (but this does not mean those processors won’t have some other component to go through to talk to the outside world, where that other component may not be hard real time). If you are going to do this without external hardware, then I suspect using one of those R5 cores is your best bet, but likely you are better off with some sort of external hardware help.
You never mentioned the nature of the data (e.g., analog or digital, resolution, sample rate, bandwidth requirements, so on), but someone answering this could probably use that information. You would need to provide a lot more detail before anyone can give more specific practical advice.
Thanks for your response. What we have in mind is this, using a A/D converter such as the USB to RS485 converter to stream signal data into the Jetson nano from an MPPT which is the same used when working with raspberry pi but do not know how to do this on Jetson nano ( don’t want to break anything😁) while also connecting the current sensor to the inverter output load.
The plan is to stream these data to our mobile and web app via Jetson nano rather than a raspberry pi.
In theory you could use RS485, but I only know about the RS232 in terms of actual use and setup (RS485 probably has some hurdles to get past, whereas if the speed is not too high RS232 would “just work”). Serial could certainly work, especially serial over USB (although USB has its own issues if you want low latency real time). Do you have any example A/D converters you’ve been considering, along with a URL with the specs? It might be possible to get an idea by looking at those and perhaps expanding on the topic. Especially useful would be to know how many A/D converters, what resolution, and what kind of bandwidth or update rate you are looking at. If you have a unit you are currently using with an RPi, then it might be useful to see the specs on that.