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Please suggest a suitable Raspberry Pi for data logging

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rstofer:
There's far too little information to make any real recommendation other than in response to 'which Pi?'.  Even there, it depends...

How far apart are the sources from each other and the host?
Is the code in the remote units changeable?  Could we scrap the serial port and substitute SPI?  I2C?  Gain control of the serial port so RS485 becomes practical?

How often are the remote units polled?  Milliseconds or hours?

What happens to the data when the host receives it?  Is it placed in a file on a USB Thumb Drive?  You certainly can't plan to interchange the microSD card although the host can provide access to the file.  Or is the data forwarded for storage elsewhere?  Perhaps it is massaged with LibreOffice  and presented as a spreadsheet and graphs.  Is this done on the host (certainly possible given Linux) or on some other machine?  How does the data get there?  Any opportunity to just stuff the data into a SQL Server somewhere?  Where?  On the local host?  Then the database could be queried from anywhere on the network for custom data analysis.

Grabbing data is the least part of the job.  Data without analysis is pretty much useless.

So many questions...  One thing Linux buys is future proofing.  Given a full OS with a complete network stack, anything is possible.  A small micro would have to shove all the work uphill to another host.

I have a couple of PI 400s and they're pretty slick.  I also have a large assortment of the other PIs but if I had to create a host for this project, I think I would go with the 400.

BTW, I could create an isolated network with DHCP and DNS running on the host.  It would be easy to use Ethernet for the remote sensors (hard wired) and WiFi to provide a link to some uphill network thus keeping the data network isolated.

The possibilities with PI/Linux are endless, the Arduino, less so.  It could still be workable, depending...



rstofer:
That GPIB device is going to be a hassle.  There is a workable Arduino project.  The video is just a small portion of the project and really deals with Brown Out Detection for the converter.



There are many other Arduino GPIB projects.  Like:

https://duino4projects.com/open-source-hardware-gpib-usb-adapter/

This project winds up as a virtual serial port under Linux so at this location, make sure the PI has USB host capability.  Again, the PI is just a network interface sending data to the upstream host.  Depending on location, it could also plug into the main host.

Remember that Linux is not exactly a real-time OS so sampling/scheduling is a more difficult problem.  Maybe the ESP devices are better for the remotes.

https://courses.engr.illinois.edu/cs423/fa2012/05-sched.pdf

This would take some experimenting.

eugene:
The right Raspberry Pi would be whatever one you can acquire, which is none of them at the moment.  :'(

The Teensy 4.1 has a micro SD card slot to store data and might be either easier or harder to code than a RPI, depending on exactly what you need your code to do. You can add a small touch screen if needed and use the libraries from Adafruit, or just power down the Teensy, pop out the SD card, and read the data on your laptop computer.

ledtester:
What kind of data logging do you want to do? Digital? Analog? How many samples per second do you need to log? How many inputs do you need to monitor?

Note that the Rpi doesn't have any ADC units so if you want analog you'll have to get an external ADC module. If 10-bit resolution is adequate then a simple Arduino Uni/Nano might work for you. For higher resolution you can get modules like the ADS1115 which give you 16-bits.

Jester:
I picked up a used pi4 model B on Kijiji for cheap.

I want to use it to capture voltage measurements from 3x 34401As via GPIB perhaps every 10s as well as temperature.

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