Raspberry PI

[Tin Falcon]

for all the computer geeks out there or would be computer geeks.
you may have heard about raspberry PI . allied Electronics in theory carries them but they have been on back order. Today I got a call from my allied sales rep. they have some currently a couple thousand in stock but expected to go fast.
this is mostly a platform to learn programming. It is Linux based but Alibre office will run on it.

tin

 

[kf2qd]

Another board that is similar is the BeagleBoneBlack.

 

[///]

Element14(Farnell) and RS Components also stock them.

 

[goldstar31]

Before Christmas, I bought my Model B as a kit from Maplins in the UK. Obviously it was more expensive at around £80 but I still had to add an adapter to use a HDMI cable on an oldish monitor. Again, the reason was really old age and arthritis in both hands and all that jazz.

Almost 6 months later, every question on how to fasten a couple of motors to assist those ancient mitts have not materialised.

For those who might be interested, I can assure you that it does everything which it says on the box. In an bitter comment, mine is back in the box!

 

[Tin Falcon]

I have pondered adding this for I/O.



http://www.farnell.com/datasheets/1682890.pdf
Tin

 

[Tin Falcon]

Goldstar to run motors you need an add on board like a gertboard or a pi face. and you will likely need to do some programming.
I have have seen where a guy used a joy stick to contol a 3 axis camera mount . the fire button activates the shudder.

I am still awaiting the arrival of my computer. should have it tomorrow.
In the mean time I did some local shopping found a HDMI to dvi converter a hdmi cable a card reader a usb hub and a couple of 16gb sd chips.

I downloaded a copy of the win32diskimager and the weezy-rasbian.img fie and burned the image to a couple of boot cards. I made an extra for a friend. so tomorrow night will set it up a boot it up.
Tin

 

[goldstar31]

Tin,
Thank you for your information. However, the points regarding the initial program for the Raspberry itself are answered for most UK purchasers as the Maplin kit contains the programs.
Moving on, the suggested Gertboard is not UK easily obtained and the question of power through one or perhaps its UK equivalent is open to question. As far as my simple mind grasps the information, no one has really said something like 'You need a x driver with Y voltage transformer going into perhaps 2 X Z Stepper motors to drive a small lathe ( say a sherline or say a small mill)

Each time I try to get my head around the problem of a shopping list( I said Mrs B's famous Cook Book) I get some geezer 'waffling on'

Apologies but I am quite happy to prattle on about the joys of some piece of music or art but in engineering and a lot of other scientific topics - 1 plus 1 equals 2.

This, Tin, is not happening. Meantime, my apologies but I didn't want to rant or moan.

Meantime, good luck with your own experiments

 

[Tin Falcon]

Well GS life goes on. I am learning to . I am finding talking to folks that the rpi is not well suited to motion control . but the beagle bones black is showing promise in that area.
so in the mean time will learn what the rpi can do may use it as a video player.
and to learn some programming.

This is a forum all points of view are accepted as long as they are presented in a respectful manner.
thanks for the pm .
It has been a rough weekend for me as well. will respond to the pm when I have more time.
Tin

 

[Wizard69]

Well GS life goes on. I am learning to . I am finding talking to folks that the rpi is not well suited to motion control . but the beagle bones black is showing promise in that area.
so in the mean time will learn what the rpi can do may use it as a video player.
and to learn some programming.

This is a forum all points of view are accepted as long as they are presented in a respectful manner.
thanks for the pm .
It has been a rough weekend for me as well. will respond to the pm when I have more time.
Tin

It does look like getting LinuxCNC to run on Raspberry PI is still a challenge. I've been following the thread on the LinuxCNC forums but it looks like the major players just don't have the time to get the realtime system running well own the platform. I'm not sure if that means the task is impossible or not.

As you have noted though other low cost options are coming on line pretty fast. I don't think the day is far off where we will see a sub $50 an ARM based board that can run LinuxCNC well. The Beagle Bones Black board is very interesting indeed and seems to have the right combination of RAM and I/O.

The problem with LinuxCNC is that it is a rather demanding but very capable CNC system. What the world really needs is a trimmed down two to three axis system for driving lathes, mills and routers. Something not as demanding on the computing hardware, open source and as reliable as LinuxCNC. Unfortunately I have neither the time nor programming skills to offer such a beast. Thus I have to wonder are you currently trying to get LinuxCNC running on Raspberry PI and have you tried anything else? There are a couple of other GCode interpreters out there.

 

[Tin Falcon]

As expected I had the raspberry pi in hand yesterday. did not relay have the opportunity to set it up until this evening.

ran into a couple minor glitches. first of all was thinking I have a usb keyboard around realized i do not. I do have an adapter to make one usb but not sure where it is did not take time or energy to look so borrowed my Logitech wireless mouse and keyboard that uses a thumbnail sizes usb dongle.
then went to hook up the monitor only to find my hdmi to dvi converter hits against the monitor stand so had to borrow the monitor off the main household computer.

all in all things went smooth followed the instructions from this site.

http://www.engadget.com/2012/09/04/raspberry-pi-getting-started-guide-how-to/

The pi has a web browser Midori and scratch pre loaded. scratch is a programming language for kids developed by MIT life long kindergarten ininiatitive . Looks like a lot of fun stuff over three million projects to date.

I purchased this more for learning python scrips and some programming .

it m ay become a video player or a juke box . or I may use it to browse web sites and free up my laptop for other things. time will tell .
the next step will be redesign the mount on the monitor so i can attach the cable need to do some metal work.

I have a PC with MACH3 for the CNC Stuff and I need push though learn and use that as well. I need to focus and not go off on tangents.
Tin

 

[rodw]

Good luck with it Tin. I bought one for a bit of a play a while ago and used a Logitech wireless keyboard (which from memory had a track ball built in) and it all came up straight away.

I thought the Pi was underpowered for surfing the Web, so music is probably a good application.

As far as interfacing with the outside world, I really think the Arduino is a much better option but can see the networking and Unix distro etc of the Pi may be an advantage.

I may be biassed as I have done heaps of C programming but I am about to pull the trigger on some arduino stuff for Chuck's Rotary Table project. It gives really simple ability to link with a myriad of sensors etc and is really easy to debug as you can get it to send output back the USB interface where it is displayed on screen in the IDE environment. Setting the Arduino up to talk to the outside world and sending the data via USB to the Pi to display it in a nice graphical format is probably quite doable and probably a lot cheaper than the Gert board. You could also send commands from the Pi to the Arduino too.

 

[goldstar31]

I am in complete agreement about 'not going off at tangents'. I mentioned amusing little stepper motors and wide-eyed children but when I want to see the 'wheels turn' I want them more substantial. Again, I don't want to turn a piece through a few degrees as in dividing head or rotary table. Others may- but not me. The pain from my arthritis in my hands is not going to be eased - it will get only worse.

I suspect that that there are a lot more punters who want to see the wheels turn-- and keep turning.

Having said that, it all interesting -academic but not me.

Regards

Norman