Raspberry Pi lauched today

Today the Raspberry Pi board lauched at price of 35USD:

It really outperforms the Arduino Ethernet boards both on performance and on price (40% cheaper than Arduino Ethernet):

•Broadcom BCM2835 700MHz ARM1176JZFS processor with FPU and Videocore 4 GPU
•GPU provides Open GL ES 2.0, hardware-accelerated OpenVG, and 1080p30 H.264 high-profile decode
•GPU is capable of 1Gpixel/s, 1.5Gtexel/s or 24GFLOPs with texture filtering and DMA infrastructure
•256MB RAM
•Boots from SD card, running the Fedora version of Linux
•10/100 BaseT Ethernet socket
•HDMI socket
•USB 2.0 socket
•RCA video socket
•SD card socket
•Powered from microUSB socket
•3.5mm audio out jack
•Header footprint for camera connection
•Size: 85.6 x 53.98 x 17mm

The reason I am looking at it is that I need wireless internet, and with this board you just plug in a cheap wireless USB stick and Linux handles the rest.....

The RPi is a great little device, and has a lot of potential within the education and hobbyist/enthusiast world. But they are quite different devices.

Arduino is a lot simpler and quicker to set up, the learning curve is a lot ‘shallower’ so easier for beginners to teach themselves. Arduino goes from unboxing to your first project faster than (probably) any other similar system out there. The number of examples and libraries available to Arduino is also a big strength (but RPi gets linux packages…). Arduino packs a large number of flexible inputs/outputs on a small and low power footprint.

The RPi allows for potentially massive projects with all that processing power, ram and connection options. Running linux and having access to all the associated software etc will open a lot of possibilities that weren’t possible with Arduino (eg dynamic web pages with javascript and php). But the flip side of this adds complexity of designing projects, which may make it harder to pick up. The RPi has some limitations on the GPIOs, there are no analogue inputs, there is only 8 I/O and (AFAIK) there is no PWM output.

For web/network based projects (eg home automation) then the RPi may become the device of choice, as they are cheaper than an Arduino Ethernet and more powerful. But Arduino UNO/Mega etc will still be a good choice for standalone/serial projects that need a lot of I/Os (eg robotics).

Don't think competition as these two is a win-win!!

The Raspberry and Arduino make very good companions, the Arduino does the device IO and the Raspberry does a nice presentation through web etc.

How many times did we see requests for projects that could perfectly be solved by these two systems.

And yes I hope that someone will port the Arduino development stuff to the Raspberry - assuming this can be done. And with a webinterface so I can reprogram my Arduino over the intenet easily. Then the combination would be even be more fun! so many dreams ...

so many dreams ...

And so little time/money :slight_smile:


Rob

Ordered mine today.

It does make a person look at an 8bit, 20MHz ATMega328 (etc.) and scratch his head wondering why a 32bit chip running at 700MHz only costs 3x as much. It's not that boards like the Raspberry PI are so powerful, but rather that the Arduino chips are so comparatively weak.

Don't get me wrong, I understand that there's a place in the world for chips like the ATTiny. I'm just saying that there's a huge gap that exists between microcontrollers and microprocessors like the ARM.

I don't think the Pi is a 'threat' to the basic 328p arduino boards, but as a direct competitor to the overdue Due, it could have an impact.

Chagrin:
It does make a person look at an 8bit, 20MHz ATMega328 (etc.) and scratch his head wondering why a 32bit chip running at 700MHz only costs 3x as much. It's not that boards like the Raspberry PI are so powerful, but rather that the Arduino chips are so comparatively weak.

Don't get me wrong, I understand that there's a place in the world for chips like the ATTiny. I'm just saying that there's a huge gap that exists between microcontrollers and microprocessors like the ARM.

Microprocessors and microcontrollers are made using similar techniques and as such there is a finite limit to how cheap they can be made regardless of how simple you make the architecture. You also need to consider the volume of sales, ARM processors are commonly used in smart phones which means they are produced in massive amounts, thus reducing the price further.

Arduino was always stretching itself when moving into the world networking/web and always needed a separate server to make ‘decent’ web pages.

Creating a web application that runs on RPi that allows you to write code for, and upload to, an Arduino might be possible in time. It would require a web based file system, a web based text editor and cli control for the ide (the first two already exist in various forms, the cli control is apparently on the Arduino team’s task list)

I think the obvious question to ask is: "has anyone implemented an Arduino-compatibility layer on the RasPi yet?"

I think the obvious question to ask is: "has anyone implemented an Arduino-compatibility layer on the RasPi yet?"

What would it be?

The raspberry has typical other interfaces than an Arduino,

Chalk and cheese. When I get my Pi it will be at the other end of the USB cable to my Arduino. They aren't comparable because the Arduino is a micro-controller and the Pi is a computer. Your phone may be a computer, but your central heating boiler isn't - but it probably has something very akin to an Atmel 328 inside it. If you want a computer you get a Pi, you want a micro-controller you get an Arduino, the price / performance doesn't enter into it. You want chalk you buy chalk, if you want cheese you buy cheese.

pluggy:
Chalk and cheese. When I get my Pi it will be at the other end of the USB cable to my Arduino. They aren't comparable because the Arduino is a micro-controller and the Pi is a computer. Your phone may be a computer, but your central heating boiler isn't - but it probably has something very akin to an Atmel 328 inside it. If you want a computer you get a Pi, you want a micro-controller you get an Arduino, the price / performance doesn't enter into it. You want chalk you buy chalk, if you want cheese you buy cheese.

While your right the RPi is a computer and the ardunio is a microcontroller, the lines are being blurred. The RPi has a useful number of GPIO and several communications systems, so it is able to do many of the (simpler) things a microcontroller can. There is already a python library to access the GPIO via python (and I am sure modules for C++/perl/ruby etc will turn up soon enough).

Most arduino of home automation systems essentially just turn things on and off over the network/internet, often with a php/ajax/fancy frontend (provided by a separate server). This whole arrangement could be replaced by an RPi.

There are projects where the 8 IOs won’t be enough or you need pwm, and in that case Arduino will still be the best option. But you can’t overlook the fact that an RPi is cheaper than a Mega; sure they are different, but at that price point there is a lot of potential overlap.

The R Pi would be useless for what I do with an Arduino which involves a degree of timing, the Arduino can happily time things to a single millisecond (a single microsecond if you push it) and it has degree of accuracy (even the Uno with a ceramic oscillator), the R Pi having a powerful multitasking operating system couldn't be depended on at all, if some other stuff it was doing (like system maintainance) was guzzling the clock cycles what you thought should happen in 10 milliseconds might take 10 seconds. The puny 8 bit processor in the arduino only does the task in hand and it doesn't have a system to maintain.

pluggy:
The R Pi would be useless for what I do with an Arduino which involves a degree of timing, the Arduino can happily time things to a single millisecond (a single microsecond if you push it) and it has degree of accuracy (even the Uno with a ceramic oscillator), the R Pi having a powerful multitasking operating system couldn't be depended on at all, if some other stuff it was doing (like system maintainance) was guzzling the clock cycles what you thought should happen in 10 milliseconds might take 10 seconds. The puny 8 bit processor in the arduino only does the task in hand and it doesn't have a system to maintain.

You are right, out of the box the arduino will be the best choice when it comes to time critical processes.

But you could install a real time kernel and access the GPIO registers directly from your code (rather than using an abstraction layer such as the python module). At that point you essentially have a industrial CNC controller, which (depending on the implementation) could be as accurate as the arduino.

Having said that, I'll be stood in line when they start delivering the things......

Horses for courses.

pluggy:
Horses for courses.

Pretty much.

Ordered mine on the day and got a delivery date of 14th April. Now I have just got an email saying the 15th May.

Theres a post on the raspberry pi front page regarding that GM, they say it was in error and the original dates hold.

I was busy on the day, and they'd been reported sold out by the time I realised they'd gone on sale. I'll hang on until the rush is over I think........

Yes I just went over to the web site after I posted this and found they claim it was an error. We will see.

I'll hang on until the rush is over I think

Not much point as Farnell have never taken money from me for something that has been out of stock and on back order before. They always charge the credit card once stock is allocated to you.

I've registered interest with Farnell which is all you can do at the moment. I'll see how it goes.