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Topic: What can I do with an RPi that I can't do with a laptop + Arduino? (Read 855 times) previous topic - next topic

travis_farmer

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For one day only, a glimpse of my latest SoC project.
\

Kinda like my server rack monitor project, though yours has far more horsepower (nice generated graphics)...
as of writing this, it appears mine has crapped out. not very reliable i guess  :o

~Travis
Current Obsession: Ham Radio, and my CNC Router
Check out my website, i have my own forum on my hobby server.

msssltd

Out of curiosity, what are you displaying the images on? Are they just visible on a browser or do you have a screen attached to the RPi?
It is a Banana Pi (not RPI) and runs headless with the GPU disabled (no HDMI output).  No point wasting power and CPU cycles on the video display as it will be installed in a data-centre.  The board has a TTL UART for direct console access, which is useful when I mess up the SSH config ;)

If I wanted to embed a display, I would probable use one of these
http://www.digole.com/index.php?productID=1269
As it's easy to drive directly from a UART.



msssltd

What have you done to your server Travis? Maybe I will regret asking :D

The horsepower being monitored is currently spread over two physical servers, 6 virtual servers and the associated network kit - I only linked to one of the monitoring pages.  The graphs are generated from MRTG (perl script) but I am slowly migrating to RRDTool.

travis_farmer

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What have you done to your server Travis? Maybe I will regret asking :D
the server is fine, but the arduino server rack monitor seems to have crapped out. i don't think it likes the PC PSU powering it. i will have to figure something else out for the PSU i guess.

~Travis
Current Obsession: Ham Radio, and my CNC Router
Check out my website, i have my own forum on my hobby server.

westfw

I can't think of anything that the laptop+arduino can't do (maybe "interface directly to a variety of cameras", but that's mostly fulfilled by cheap USB cameras for the laptop anyway.)  RPi can easily be smaller, cheaper, and lower power, compared to most new laptops; but old laptops can be had really cheaply.   The vendors selling RPi "kits" with all the bells and whistles, at a price approaching a "real laptop" sort-of annoy me.  But a $5 Pi-Zero connected to a cheap NTSC monitor will go places that I wouldn't/couldn't put a laptop...
(Now, cheap android tablet or old phone plus BTLE-enabled Arduino is yet another interesting platform...)

Delta_G

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What can I do with an RPi that I can't do with a laptop + Arduino?
1.  Fit it in a really small space.

2.  Blow it completely the F up and walk away not feeling like you lost too much.

And that's about it as far as I can see.  #2 by itself is enough for me. 
If at first you don't succeed, up - home - sudo - enter.

wildbill

There is little that you can do with an RPi that a laptop and arduino can't, physical space requirements notwithstanding. Where the Pi wins out is when you have multiple things you want to do in disparate locations.

I have a Pi in my dining room acting as my GIT hub and sending temp and humidity data to a LAMP server. I have another one in the basement that will text and email me if it detects moisture. One on the other side of the basement controls a grow lamp and sends temperature data.

That said, there are cheaper ways to do the sensing stuff. A killer app for the Pi would be one that requires more processing power.

MAS3

And how is that a win to an Arduino with some kind of network shield for any 3 of them ?
I don't know what applications you are running on those 3 Pi's but i can't imagine this can't be done by an Arduino.
A Pi seems quite a bit of overkill for that to me.
Have a look at "blink without delay".
Did you connect the grounds ?
Je kunt hier ook in het Nederlands terecht: http://arduino.cc/forum/index.php/board,77.0.html

wildbill

Yes, it is a bit upsetting to be running a temperature sensing app on something with that much horsepower.

The thing that pushed me that way was that I had an Arduino with a wifi shield doing the job, but I had to replace my cable modem and it wanted WPA2 which the shield couldn't handle. I had a Pi that could and that was that. Besides, I like Linux ;-)

pert

I think it would be quite tricky to run a Git server on any Arduino.

westfw

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I had an Arduino with a wifi shield doing the job
Adding either Ethernet or WiFi to an Arduino tends to push it's cost up higher than a similarly equipped Pi :-(
A RPi has ethernet, WiFi, USB Host, SD, and video out built in for $35...

Robin2

I bought a few ESP8266-12 modules a while ago and I finally took one out of its bag so I could experiment with programming if from the IDE.

I know you can get the modules on a breakout board but I want the smallest possible footprint for one application so I won't comment on the inconvenience of using the module.

It does look like a very cheap and convenient way to create a node that just requires limited functionality - such as reading a sensor,

I guess the reality is that there is a lot of overlap and underlap (if there is such a thing) between all these products. I can see how it would be difficult for a novice to choose between them and s/he will probably start with whatever is recommended by a friend or teacher. And it is only in the edge-cases that the choice really matters.

For example my interest in a very small device is to fit radio control into an 00 Gauge model railway locomotive. However what I learn from doing that might open up other opportunities for using devices where size is not important.

I started this Thread because I was concerned that I may have been overlooking something - but it seems not. Thanks for all the input.

...R
Two or three hours spent thinking and reading documentation solves most programming problems.

AWOL

The ESP 8266 devices are brilliant for environmental sensing with WiFi.
I have multiple nodes with BME280, one-wire temperature sensors and OLED, around the house.
"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.
I speak for myself, not Arduino.

Delta_G

OK, I think I've finally hit the Pi point here. 

I'm building a little tank robot with an arm on top and a camera a transmitter so I can drive it FPV.  There's a 1284P chip that runs the whole main bot and a nano that runs just the arm.  The whole thing is designed to be totally agnostic to the communication style.  It just takes commands over serial.  Right now I've got a ESP8266 set up to get the commands over wifi through a TCP socket and pass them on to the 1284.  When I started testing, I was controlling it with an XBox controller hooked up to my computer with all the code written in Python.  Everything was going great but I wanted to build a base station for it.  I had a Mega and another ESP8266 and a USB host shield so I thought I'd give it a go.  It was pretty easy and it works great, but now I have to convert all of my beautiful control code in Python over to C++ to move it to the Mega.  I ended up writing a lot of code there.  I've already rewritten a bunch of it for the Arduino, but even now I'm still testing new ideas and I tend to find it easier to develop them in Python first.  When you're at that tweak it - run it - tweak it - run it - tweak it - run it stage it is just easier to be able to run the code on the same computer you are writing it on and not to have to compile over and over. 

So I think the answer is to build my base station on a Pi instead of a Mega.  I can do better display that way on a TFT in the base station.  I can probably handle a little bit of video stuff.  And I can work with the same code in Python that I use on the PC. 

So I'm about to start shopping for a Pi.  I knew this day would come. 
If at first you don't succeed, up - home - sudo - enter.

JMeller

I'm in a similar space.  My neighbor bought a $2k scaled WWII boat he wants me to build the controls for i.e., rudder, motor, turret position, turret firing of ball bearings, "radar", etc.  All was well within my scope of an arduino head-end- until he mentioned FPV cameras on the turrets.  After doing some research, the arduino is only capable of 3-10fps of streaming.  After knowing only the tip of arduino coding iceburg, it seems I'll need to learn yet another language.

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