which new type of the Microcontrollers to learn?

Go To Last Post
194 posts / 0 new

Pages

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

How many times has virtual machine been mentioned? Run the linux in a virtual machine under windows and avoid the issue of dual boot or wrecking windows. Cliff likes virtualbox and i've used vmware. You can download pre set up images off the web.

https://www.virtualbox.org/

http://virtualboxes.org/images/u...
Note ubuntu 12.10 runs slow on the VM. Kubuntu might be better.

http://virtualboxes.org/images/k...

There's also a few youtube vids that show you how to do it.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Dual booting on an usb stick/usb disk is quite comfortable (I do it with Fedoras : the grub boatladder in installed by default, at least on FC19beta -for the other, I forgot but managed anyway to have the bootloader installed on USB sticks disks- on the external device, which avoids "the issue of dual boot or wrecking windows" as the internal disk remains ignored until one explicitly mounts it).

Advantages are you can emulate (with qemu-arm) softwares before putting them into a real arm -or even buying it!-).
If one tries to emulate -with virtualbox, vmplayer or even with qemu-x86 - linuxes, one should choose lightweight dektops -if any-, as desktops eat a lot of RAM -and this RAM is stolen from the host system....

The fact that rapsberry Pi has less output functionality than the mini is operhaps a wrong drawback : as it is cheaper and more popular, extensions cards are being made (elektor begins to design some). Annie Way, it is likely to be slow (but the definition of 'slow' varies and one can begin with a RPi and buy a more expensive ARM if needed) and its sharing the USB bus with a lot of hardware -there is only one USB interface: most PCs have at least two- can generate unpleasant lags.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

i hope that still i can connect a hob on the rosbperi pi's solo USB port, conecting a mouse and keyboard to it and observing the
system through a TV connecting to its video output right? if yes still i believe that the Ropberi can do fine. then i will buy it soon and try
programming on it directly.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

You can use an (and more) USB hubs with rapsberry, but this wonot increase the speed of the unique USB channel (it will share poverty). For keyboards and mice, it does not matter but it would add lags if you had the USB for ressource greedy peripherals (PCs have two USB bridges, AFAIK, for better transfer speed -exemple: copying big files betwween two sticks, while having a webcam, the keyboard and the mouse- working). What makes the RPi interesting (at least for testing and learning) is its price (some arduini mega are much more expensive ) and the fact there is a lot of support and help.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

so it will work with a mouse, keypad and webcam conected to its USB right? i am sure that i wont have any large files tranfered on it. ok then lets buy it already!

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

"i am sure that i wont have any large files tranfered on it."
I am not that sure (suppose you want to add/upgrade software and have no *direct* Internet connectivity : solution is to download (from an internet café, say) missing softwares and put them on a USB stick, which can be put into your hub: then, transferts maybe rather slow and erratic -but data transferts are without errors-, webcam can lose som images -webcams are meant to be fast, but mising a frame is not problematic- and mouse and keyboard should work as usual)
As it is not cheap -and can be used as a classical PC for text editing, compiling, learning Python, say- the price of an error -if any- is not that big. And most of the binaries you can find on the Net are maintained by Debian : they are often fully tested and very stable...

BTW : if you want to backup everything you have put into it (it may be wise, before major modifications), that can amount to large file transfers (another solution is to remove the SD and to "plug in" into a PC)

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

sure the OS itself is run from the SD card, this SD card plays the role of a hard drive here and wil handle the file transfer i suppose.
the webcam is not going to function by itself, it will be my software to comand it and ask for a fram. a sum of 10 frames
per second will do and the images are not needed to be large scaled.
thank you for the advises Mrs.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

also a friend of mine said that we are working on the OV7670's functions on the RPi. if thats true i would not need
a webcamera utilizing their work.
this Ov7670 is a challenge for itself, it has about 200 control registers and i dont even know which ones are prominent to work.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Quote:

it has about 200 control registers

The point of using Linux is that the chances are the kernel already has support for it and if it doesn't yet then you can just borrow the kernel driver code your friend has done so you don't have to re-invent the wheel. In a small way Arduino is a bit like this - one person works out the complex bits of using a device so everyone else can then just use simple code/interface. Linux is the same but on a larger scale. It's actually pretty unusual to have to write a driver from scratch - usually it'll only be the original equipment manufacturer who actually does this for you.

EDIT: Yup, 2 seconds with Google gets me to here:

http://lxr.linux.no/#linux+v3.9....

So tell your friend to stop wasting his time - OV7670 is already in the Linux kernel (as are drivers for almost every peripheral you can ever think of).

The KConfig for that driver is here:

http://lxr.linux.no/#linux+v3.9....

So just search that symbol when you configure the kernel and enable it - then the kernel will already have OV7670 support built in and you can access it though V4L2 (you can see in the config that it:

 depends on I2C && VIDEO_V4L2
 depends on MEDIA_CAMERA_SUPPORT

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Quote:
this SD card plays the role of a hard drive here and wil handle the file transfer i suppose.

When you copy something from (or to : backups ) the outer word, there are two scenarii:
a) you have a direct Internet connection, and the outer file travels through the Internet plug and the SD connection : I agree the USB is not involved.

b) you have no direct connection, and do not want to use your PC (unlike AVRs, you can develop directly on RPis and their equivalents: PCs are no more mandatory) as a relay (maybe it is the solution?): the only solution is to plug an USB stick (external drive?) into the hub, thus sharing its band pass -which is limited- : tranfers will be shaky (integrity of mass storage is granted, but not the speed) in order to keep the mouse/keyboard (maybe webcam : one can do a backup with other applications running) responsive. (even on PCs -they have more USB channels- , copying on external disks/USB sticks can have strange time lags)..

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

clawson wrote:
Quote:

it has about 200 control registers

The point of using Linux is that the chances are the kernel already has support for it and if it doesn't yet then you can just borrow the kernel driver code your friend has done so you don't have to re-invent the wheel. In a small way Arduino is a bit like this - one person works out the complex bits of using a device so everyone else can then just use simple code/interface. Linux is the same but on a larger scale. It's actually pretty unusual to have to write a driver from scratch - usually it'll only be the original equipment manufacturer who actually does this for you.

EDIT: Yup, 2 seconds with Google gets me to here:

http://lxr.linux.no/#linux+v3.9....

So tell your friend to stop wasting his time - OV7670 is already in the Linux kernel (as are drivers for almost every peripheral you can ever think of).

The KConfig for that driver is here:

http://lxr.linux.no/#linux+v3.9....

So just search that symbol when you configure the kernel and enable it - then the kernel will already have OV7670 support built in and you can access it though V4L2 (you can see in the config that it:

 depends on I2C && VIDEO_V4L2
 depends on MEDIA_CAMERA_SUPPORT

====
good! its settled then. i will tell them about your discovery! ur replies are always a direct hit to the answer sir.
now i will have to share the USB only with the key/mouse/memory and it will do fine.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

very well people i will report back when i have the actual hardware at hand and have begun trying the Linux.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

oo great the sales man said that they dont have Rasbperi available but the new "Marsboard". it seems that this one is not really better than the RPi. it also works with the android but has on chip NAND flash.

which one should i choose?

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

You may reprogram a SD card on a PC; it is more complicated with NAND flash -though amovible disks are not such reliable and may get lost -
RPis seem to be very popular , and have a very good Linux -Rapsian- avalaible ; marsboard seems to be better HW, a little more expensive, with -to day- a slightly less good software...

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

the Android is more difficult than the Linux to work with right? it seems that the Linux is also available:
http://www.marsboard.com/downloa...

but some users compalin that it comes with no softtware support and some even claim that this marsboard might has some HW failours:
http://www.raspberrypi.org/phpBB...

i am kind of feeling that the Rasbpri might be a better choice specially since many people have utilized it. despite the declared stronger hardware set on the Marsboard which should be good if it was working actually.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Quote:

the Android is more difficult than the Linux to work with right?

Android is just an application shell on top of Linux - while the writing of the apps is a bit different, under the hood it's all still Linux.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Clawson, I just tried to install OpenCV using your example, and it couldn't find it, but mentioned "LibCV" being available. I did some checking and it looks like they are the same thing...? I'm using Ubuntu 10.04 in a VM. I don't get why your cmd string didn't work , if they are.

I changed it to "...Libcv..." and that installed.

1) Studio 4.18 build 716 (SP3)
2) WinAvr 20100110
3) PN, all on Doze XP... For Now
A) Avr Dragon ver. 1
B) Avr MKII ISP, 2009 model
C) MKII JTAGICE ver. 1

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Well, there are some features with mars:
a) 4 kind of Linuxen can be put on it( Ubuntu, Fedora, "Linux" -maybe home-made - and Android). IMO, Fedora and Ubuntu are slightly less good than Debian (and Rapsbian is a Debian adaptation) : it remains a matter of opinion...

It is amusing to notice that Rapsbian repositories have at least avrdude, avr-libc -and, according to http://mikehw.rddev.co.uk/?cat=6, avr-gcc ....

b) it has interesting extensions : 140 pins on a 2 mm header. As most of the connectors are 2.54 mm spaced, it seems very cruel for hobbyists....

c) NAND flash is faster than SD and it boots from both making one of my objections (booting *only* from NAND: a reliable solution would consist, for the RPi, of having 2 SDs, one under test, the other as a backup) invalid...

Support is described as being essentially ... non existent... but maybe it is linked with its youth.... (RPi has been described as vaporware one year ago)

To day, RPi seems very popular and how to build a "home made" Linux -if really necessary: it **is** long - is well documented in GNUlinux Magazine France .
http://www.blaess.fr/christophe/... (I bet there are a lot of other papers on this topic).

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Quote:

and it couldn't find it, but mentioned "LibCV" being available. I did some checking and it looks like they are the same thing...? I'm using Ubuntu 10.04 in a VM.

Checking here:

http://packages.ubuntu.com/

Seems to suggest that libopencv-dev was not available in "lucid" but is, clearly, available in "precise" (the 12.04 I'm using). I also checked "lucid-updates" and "lucid-backports" and it wasn't in either of those. So for 10.04 I guess you had to pull it from another source or build it from scratch.

If you search "opencv" in lucid all you get is:

http://packages.ubuntu.com/searc...

While the same search in precise gives:

http://packages.ubuntu.com/searc...

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

"So for 10.04 I guess you had to pull it from another source or build it from scratch. "

I had it installed from the sources for a Fedora17 and the way I did was very like http://www.raben.com/content/ope... (then I could test without any difficulty Clawson's example)

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Thanks, then I'll install a 12.04 VM.

1) Studio 4.18 build 716 (SP3)
2) WinAvr 20100110
3) PN, all on Doze XP... For Now
A) Avr Dragon ver. 1
B) Avr MKII ISP, 2009 model
C) MKII JTAGICE ver. 1

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

so.... are you suggesting that the Raspbri is a better choice?

i believe that the MARSBOARD will be yet a better option but after a year passes now!

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Whiteman - if in doubt - buy both! Then you can determine yourself which one is better for your requirements. It's not like either of them are big investments. The investment in time will usually exceed the investment in money at these prices.

After a year has passed there will be something newer and better, so you're always chasing the tail. If the marsboard is easier for you to get, get it. If it turns out to be a pile of crap, tell us and notch the $50 up to your education.

Again,get your code going on your pc first before pissing around with a rpi or whatever.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Quote:

on your pc

Using Linux installed in a virtual machine. My little OpenCV example above was supposed to show that just as I did you can do all the experimenting/prototyping/developing on your PC with no hardware but the Pentium/AMD you already own.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

yes yes i know but i am afraid to mess with my PC because it already has some hidden problems as i feel.
also these devices are cheap at your vicinity but until those reach here at this country at hand their prices get doubled! how ever i will consider that option to buy both.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

You don't appear to be getting the point repeatedly given above. You install Linux into a VIRTUAL MACHINE, there's no worries about changes to anything on your PC (except for the install of VirtualBox or VmWare). If you completely screw up the virtual machine you throw it away and start again.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

MarsBoard- CPU is a China-only ARM cortex A8. It *is* ARM, but you likely won't find it well documented in English, nor in the list of supported targets in popular compilers/IDEs.

But for $50, you can get some entertainment out of that board. *IF* you want to be a Kernel hacker.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

clawson wrote:
You don't appear to be getting the point repeatedly given above. You install Linux into a VIRTUAL MACHINE, there's no worries about changes to anything on your PC (except for the install of VirtualBox or VmWare). If you completely screw up the virtual machine you throw it away and start again.
Just put a second drive on your PC, and put Linux on that. Tell your BIOS which drive to boot. Simplest.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Installing GNUlinux is not that simple (I know it takes 15 minutes on a classical disk, and there is ONE tricky question -at most- to answer ifone wants to install on en external drive/USB key or on a free partition; but it is shying away if one did not try): Virtual Machines can be used to try installation and see what is complicated -once one has noticed it, every thing becomes simple for real hardware if one needs-.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

alright guys i really hope if you are still reading this post!

finally i could order a receipt on the RPI model B hardware and hopefully i will have it at hand withing few days!

now lets begin from the first step, which operation system should i download from their website which fits best for my applications?

:D

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

RPi recommend "wheezy" from here:

http://www.raspberrypi.org/downl...

That's a variant of Debian. It'd be best to use whatever most other RPi users will be using as you'll find more articles, forums and users willing to help using the most popular choice.

BTW if you haven't done already (and if you aren't already using Linux on your PC) install a virtual machine (VirtualBox or VMWare) on your PC then a copy of a Debian based Linux distribution such as Ubuntu so you can learn the basics of operating Linux in the comfort of your PC environment.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

as i said before i dont want to bring this on my PC, all i want is to begin programing right on the RPI itself and thats why i paid equal amount to 60$ for it while its in fact 20% of my monthly income here.

ok, so i would install the wheezy, what will be the next step sir? will that whezy has the required .h files and the C environment on it? which books will i need to study for this?

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

As to why you wouldn't do development on your PC is beyond me - regardless of your income. Compilation takes about ten times longer on the rpi than the PC. As to how to do things with the rpi - there's lots written on their forums and howtos.

If the distribution doesn't have the compiler already loaded, then you'll learn quickly about the package manager.
apt-get install gcc g++ make automake
Should get you started.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

But when you work on an embedded Linux target you always do 90-95% of the work on a desktop Linux machine. If you don't "get that" I fear you have failed to understand why you are using Linux! (don't think "you know better", you clearly don't).

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

so you mean that i should write the programs on the livedisk set at my Pc and then after making sure that its running relocating it on the RPI because loading up the compiler and testing the programs take much longer on the RPI right?

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

ok and what kind of book should i use about these? as i said before i have little idea about the whole matter.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

I just use Google. I'm trying to get a 4G modem working under linux at the moment - Google is my friend.

I've not really used the livedisk to do anything useful. As was told to you many times, most of us use a virtual machine. Load the virtual machine app on PC, download the linux virtual machine of choice. Run. The whole thing runs under windows - no dual boot or special formatting of hard drive.

Your PC is faster and has more memory and faster disk than the rpi. Much easier to develop. Once you've got the code working, either compile it on the rpi or load a cross compiler on the PC. We've also told you this before.

For questions about the rpi, what linux, howto do xxxxx then go to the rpi forums. Odds on someone has asked the same question. Personally i don't have a rpi - my Seagate Dockstar is running debian wheezy so things are much the same as is most stuff with linux.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

RPI isn't an "embedded microprocessor". It's a Linux system. May as well just use Linux on a desktop, if you are learning.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

You should test your programs on a PC first, as it is faster, has better disks;
Once it works, you can either transmit the sources on your RPi and compile ir RPi Rapsbian has a native compiler), or cross compile it -with arm-gcc, say- and transmit the resulting binaries...It might be slightly faster wit cross compiling, and storage and archieving is easier....

if you use livecd with Linux, you will likely lose settings (often use part of RAM as "disk"...) and havee trouble: either you dual boot (many GNU linuxes can be installed on USB sticks/disks if your PC is young enough to accept booting on USB) or use virtual machines (VirtualBox or VMplayer,VBox being easier - some people use it at internet cafés without any issues-).
As for books, it depends: I often use http://www.advancedlinuxprogramm... but I had GNUlinux installed -and could program what I wanted- years before I found books...

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Quote:

RPI isn't an "embedded microprocessor". It's a Linux system.

Ah the age old question of what embedded means. I work on systems that sit in a metal box under the bonnet of your top of the range BMW, Mercedes, etc. We use Linux on some of these. The overall system has just one job in the world. When you are driving along it processes the images from four cameras dotted around the car together with short and long range radar systems and when it detects something that could be a danger it takes action. To me this is an "embedded solution", like a washing machine or a microwave oven or an engine ECU or an ABS unit. In theory the software in the box will never change and it will only ever do one repetitive job. Sure it runs Linux but I don't see how that changes the fact that it's an embedded micro doing an embedded task. Linux just happens to be part of the software solution. If we switched from Linux to VxWorks or Nucleus Plus would that make it more "embedded"?

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Just to divert the discussion, i've been using kubuntu 12.10 on an embedded ( that term again) PC box and all was well except i needed a later kernel for 4G wireless support for the dongle i'm using so i loaded up Kubuntu 13.04. The thing is so slow it is unusable! God knows what they did to hobble it. The machine is a D510 quad core 1.66GHz with 2GB ram, so i would expect ok performance (12.10 was good). I'm trying lubuntu 13.10 to see if things are better. Rant over.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

sorry guys i was not around for a while because of life's engagements. i will try to put some updates as soon as possible. thanks every one for the wonderful replies.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Welcome back!

whiteman7777 wrote:
could you show me an industrial rated one please?
MYC-SAMA5D35 CPU Module
Though made in China I'm not certain you'll be able to get it.
The Atmel SAMA5D3 series (ARMv7-A) can run a Debian 7 file system image and is the follow-on to Atmel's SAM9 series (ARMv5).

"Dare to be naïve." - Buckminster Fuller

Pages