# Raspberry Pi? Anyone with any Experience?



## mosaix (Nov 29, 2015)

I'm think of asking for a Raspberry Pi kit and add-ons (or equivalent) for Christmas. Anyone with any experience / advice?

Thanks in advance.


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## AnyaKimlin (Nov 29, 2015)

I haven't but my husband and daughter both have. I know we have a Raspberry Pi and I think it powered our media box for a time but no idea how   My house is full of technology I use but don't get.

Is there anything you want me to ask them?


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## mosaix (Nov 29, 2015)

AnyaKimlin said:


> I haven't but my husband and daughter both have. I know we have a Raspberry Pi and I think it powered our media box for a time but no idea how   My house is full of technology I use but don't get.
> 
> Is there anything you want me to ask them?



Thanks Anya. Off the top of my head I'd like to know what model they went for and why. I think there an A a B and a C. I know there's also a Zero but I think that's a cut down version. Also, anything to avoid?


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## AnyaKimlin (Nov 29, 2015)

mosaix said:


> Thanks Anya. Off the top of my head I'd like to know what model they went for and why. I think there an A a B and a C. I know there's also a Zero but I think that's a cut down version. Also, anything to avoid?



We have Raspberry Pi B - he chose it because work ordered one and they sent two - he was told to keep the extra one.  It can do almost anything a low powered Linux computer can do.  

He suggests waiting for the Pi Zero to come back in stock or go for the Pi 2B because the Pi Zero is £4/$5 and it does most of the Arduino can do.  It's takes the place of the A and B.

The Pi 2B is the newest and more powerful version.  It does most of the desktop tasks for your average person and is a very good learning tool for kids. One of its competitors is the Beagle Bone Black.  They're similar in price but the Beagle Bone is better suited to a hardware hacker.  

I hope you understand that because I felt I was typing in Swahili.


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## mosaix (Nov 29, 2015)

Ever so grateful, Anya. One final question. I see there are books and magazines for the Pi. Any recommendations?


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## AnyaKimlin (Nov 29, 2015)

mosaix said:


> Ever so grateful, Anya. One final question. I see there are books and magazines for the Pi. Any recommendations?



He says Mag Pi is free online and really good.


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## Ray McCarthy (Nov 29, 2015)

It's pretty similar to any other ARM based Linux computer.

I have the "B"version. with Risc OS and the RaspberryPi Linux.

There is a huge amount of online resource.

The Pi Zero doesn't replace an Ardiuno or JAL + PIC for any real time application unless you install a Real Time OS. I'll think of something though for the Pi Zero. It's only a choice if you don't need networking, don't need battery operation and don't need Real Time.

The Pi family is basically a phone chip on a breakout board that runs various Linux Distributions or Risc OS.

For a "starter" avoid the A and Zero. The B and 2B (or is it B MkII) are fine as they have extra USB and a USB base ethernet port.
You need a 4GByte SD card,  HDMI screen (need not be full HD or a TV, some strange monitors work), 5V psu, USB mouse and USB keyboard and ethernet Internet  as a minimum to start.


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## mosaix (Nov 29, 2015)

Ray McCarthy said:


> It's pretty similar to any other ARM based Linux computer.
> 
> I have the "B"version. with Risc OS and the RaspberryPi Linux.
> 
> ...



Thanks, Ray. Do you know the difference between the "B" and the "C"?


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## Ray McCarthy (Nov 29, 2015)

I never heard  of a "C". There is more featured version of B called 2B or B2 or B MkII which has some more USB and extra I/O pins, but the original GPIO pins are in same place. Perhaps that's what you are thinking of.
Zero has GPIO pins of 2B missing, you have to solder them in, it has only one USB port (the other USB connector is for power). It has no network. I think it has no audio or composite video.
All models use SD card for OS and storage. All really use HDMI for video. The Composite is pretty pointless except for special video applications. The A, B and B MkII have a camera connector (but a very specific camera). There is also a connector for some sort of LCD panel.

You can read the GPIO pins or turn them on/off in Python. The standard distribution has Scratch and Python.

For serious I/O with accurate timing I'd use an Atmel or PIC programmed in JAL connected either to Pi GPIO or USB. The Arduino boards are expensive and for people that can't solder veroboard etc. I have one, and I think for me a waste of money as I can solder.

You could develop something that uses the GPIO pins on a Zero using B (or the newer 2B/B+or whatever it is) and then copy the SD card using DD and USB to SD card reader to setup the dedicated Pi Zero.


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## mosaix (Nov 29, 2015)

Ray, here's write-up on the model "C".

Raspberry Pi Model C

Excellent spec etc., until you get down to the bottom of the page.


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## Ray McCarthy (Nov 29, 2015)

mosaix said:


> Excellent spec etc., until you get down to the bottom of the page.


No, I knew it was a joke at the 2nd paragraph (so no Model C, yet anyway):


> “People have been whinging since day one about 100 Mbit ethernet. Frankly we’re sick of it.” Says Eben Upton, “But while we were in the Far East recently, we found a new supplier who had some really good value Gigabit chips, with matching ports.


The ethernet is via a USB to Ethernet adaptor integrated inside the USB hub chip. The ARM phone SoC used communicates via a single USB port. The B and B+ essentially don't even manage 100Mbps, as it's actually shared USB bandwidth.

So there is

A (Less RAM and no ethernet, avoid)

B (basically similar to A)

 a 2B or Mark II B, extra GPIO pins and some other changes, backward compatible to B
Zero: The USB hub chip with integrated ethernet is diched. For GPIO and HDMI it's backward compatible with A, B or B+.  Only economic for HDMI video, and/or GPIO. Though a 4 port USB hub can be got for about 2 Euro, then you can use one port for a supported WiFi stick or USB Ethernet adaptor.
Buy version 2 or 3 to learn and develop on.  Buy the Zero only for dedicated use to run one program (HDMI or GPIO)
I'd use a USB memory stick (or USB SD card adaptor) for any user storage and let the CF card be purely for the OS.

GPIO = General Purpose Input Output.


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## TheDustyZebra (Nov 29, 2015)

My son has the 2B, I believe. He has a nice wooden case for it, oddly called the Zebra Case even though it looks nothing like me (or any other zebra), which he got on Amazon from C4 Labs. He hasn't done much with it, really, but I'm thinking of getting him a couple more books for Christmas and maybe sparking ideas.


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## Ray McCarthy (Nov 29, 2015)

Farnell do a lego compatible case (I have Mindstorms 1.0 somewhere!).


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## mosaix (Dec 28, 2015)

Okay got my Pi for Christmas. 

No problems with it. Attached keyboard, mouse, HDMI TV, and network cable, installed the operating system and everything works perfectly.

It runs a version of Linux and I've used Linux and Unix for many years so I've no problem with that. I've just started playing around with the GUI.

One thing has occured to me though. I used its browser to do a bit of internet access (BBC etc) but how did it access the internet without knowing my router's (non-standard) password?


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## Ray McCarthy (Dec 28, 2015)

mosaix said:


> but how did it access the internet without knowing my router's (non-standard) password?


You used ethernet cable? Usually the password is only for WiFi. A password to connect to ethernet cable is very rare indeed.
The standard pi has no WiFi.
You really knew this and forgot. 
Have a look at Scratch. There is an update that allows GPIO port. Also a floppy cable plus simple veroboard adaptor (cut tracks between two columns of holes) allows a cheap adaptor to a breadboard for switches and LEDs (a 2N3906 to switch external +V with two resistors or 2N3904 for 0V end of relays, LEDs, or ULN2003 for multiple devices). I got a 8 x 8 RGB LED tile cheap. I'll use a mix of 2N3906 (PNP) and ULN2003 on the breadboard to drive it from Scratch or python. Though for animation it's easier to use PIC programmed in JAL (version 2.x) and either GPIO I2C or USB (the 18F PIC has easy to use USB Slave port in JAL that will look like an USB to Serial adaptor to a Pi), then you can assemble an array of tiles with cheap PIC for each one, controlled by Pi.


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## mosaix (Dec 29, 2015)

Ray McCarthy said:


> You really knew this and forgot.



Stupid of me! _:smack on the head smilie:_

Thanks, Ray. I'm so used to connecting new devices wirelessly and having to key my password...


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