I have, so far, resisted the temptation to buy a Raspberry Pi.
Just now, looking again at the RPi specs got me wondering what I would get that I don't already have with the combination of a laptop and an Arduino.
As far as I can see an RPi is just an under powered PC with accessible I/O pins.
I do appreciate that an RPi is physically smaller than a PC and more energy efficient. But for the purpose of exploration neither of those features matter.
What am I missing - that might persuade me to part with ££
Certainly the price is a consideration. RPi Zero is $15 USD or less including shipping, RPi Zero W $20 or less. Of course once you added on all the accessories that your laptop includes it will not save you much if anything but for an embedded application you may not need most of that and you can pick and choose the accessories you do use. I wish they would allow the Zero to be purchased in multiples. The $5 price would be more attractive to me without the extra $10 per unit shipping added on.
I've been messing around with the RPi Zero with the camera module for IP cameras. I got really sick of trying to work with the cheap commercial IP cameras or trying to repurpose smart phones for that use. Even though the RPi doesn't end up cheaper and is more work to assemble it's worth it to me just because it's more hackable and open. For that application the RPi is certainly superior to any Arduino but I don't foresee using them for many other projects.
travis_farmer:
i think i remember that you have said that you do well with Python. Rpi has Python libraries (so i am told) that can directly interface with the GPIO.
I can get the same effect with a Python program on this Linux laptop connected to an Arduino.
And it seems to me the higher level functions that an RPI can do (and an Arduino cannot) are easier to do on a laptop as it has has more capability than the RPi.
So, I do think I mean "what am I missing" by not having an RPi.
the benefit of using a raspberry pi instead of a laptop is that you can set the raspberry pi and then do other things with your laptop.. and the raspberry pi is considerably less expensive than a laptop.
Qdeathstar:
the benefit of using a raspberry pi instead of a laptop is that you can set the raspberry pi and then do other things with your laptop.. and the raspberry pi is considerably less expensive than a laptop.
I am aware of that and I thought I had dealt with it in my Original Post. At the moment I don't have any application that needs an RPi and if I had, I reckon I would do all the development work on my laptop and only convert to the RPi for the final version.
And I have a few other laptops gathering dust
I just want to make sure that I am not overlooking some capability in an RPi that does not exist in a combination of laptop plus Arduino.
My laptop won't run off a phone charger, and my wife won't complain if I stick a Pi behind a small TV or speaker.
(Not all my laptop's have HDMI outputs either)
I don't have an RPi but I do have a BeagleBone Black, which is essentially the American equivalent (American Pi? ). Anyway, the advantages that I see are that it can be embedded, i.e. if you need a dedicated processor for a piece of "smart" equipment that requires more power than the Arduino, and it needs to be there 24/7, and doesn't need a full-blown keyboard and monitor, then the BBB/RPi is useful. Also the BBB/RPi has a lot more electrical I/O capability for controlling external electrical items than a laptop (although that I/O is crippled by being 3.3V and low current). Otherwise, you are right. If these things are not a requirement, you might as well just get a cheap laptop.
I agree with microcat that the main benefit of an SoC is continual operation. If I didn't have a need for 24/7, low intervention, network operation I wouldn't know what to do with an RPI either.
For one day only, a glimpse of my latest SoC project. Running Armbian/Debian 8 on a Banana Pi M2+ Early work in progress but doing useful stuff in a production system none the less. I could have used a virtual server or a container but using an SoC has the advantage of decoupling the monitoring platform from the platform being monitored.
An old scuba diving buddy I know (Gordon Henderson) wrote the guts of Wiring Pi, the Arduino like programming interface for the RPI's GPIO. The electrical interface is not so much crippled, as a characteristic of working with a general purpose CPU at a much higher clock frequency (IMHO).
If you do find an application, I would warn against doing too much on a laptop first. You could end up in a corner, relying on some functionality which is not available or runs too slowly in the Arm environment.
msssltd:
If you do find an application, I would warn against doing too much on a laptop first. You could end up in a corner, relying on some functionality which is not available or runs too slowly in the Arm environment.
Good point.
For one day only, a glimpse of my latest SoC project
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?
Robin2:
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
What have you done to your server Travis? Maybe I will regret asking
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.
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...)
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.
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.
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
