newbie needs help in IO

Hi All,

I am pretty new to linux embedded. A mobile robot project I am working on requires some IOs: 3 quadrature (single-ended) inputs. two 12 bit AD inputs, one PWM output. I want to use linux embedded with PC/104 hardware. I can code in C or C++ and I want to avoid learnning assembly langrage if I can. Do I have to write my own device driver for these IO boards? Is there any company that sell the PC104 IO boards with linux drivers?

Thanks in advance.

Everett

Reply to
Everett X. Wang
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You can contact

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for their 'multi-q' I/o board. Tried and proven in hundreds of labs in universities all around the world. Great support. Runs in true real time. easy to use.

mention me if you want to.

hth

Jay

Reply to
j.b. miller

One way you can approach this is, since this is embedded system and I am assuming not on the network, you can run you program as root user, this will allow you to access all the I/O ports so you don't have to write any drivers.

The other way that we have implemented write a very simple driver that allows you to access all the I/O ports. This way you can use any hardware you like. Hope this helps.

Andy R.

Reply to
andy R.

Everett,

Can't help you if your application specifies the use of embedded Linux... (and based on the question you ask about device drivers reflect why Linux remains a rare choice for real-world systems interfacing with industrial I/O).

But if you have C/C++ programming capability, the following boards from TERN would meet the requirements you specified in your post:

- first, if you can implement your own quad decoders through polling of the input signals from your encoders, then something as simple as the A-Engine would work:

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The (former) x86-based Am188ES processor has integrated PWM outputs,

11 ch. 12-bit ADC, and plenty of digital I/O that you could use to decode the quadrature inputs. In low quantities, this would be priced
Reply to
CC Tang

FUD. Maybe you consider embedded Linux "rare" because your product line doesn't support it?

I've been working with embedded Linux in industrial control applications (real time and not) since 1999 and I wasn't an "early adopter".

Kelly

Reply to
Kelly Hall

You can get a board and support from

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Simple as that.

Jay in Greensville,Ont.

Reply to
j.b. miller

Definitely don't want to get into a religious/philosophical battle, so let me apologize ahead of time and try to back out gracefully. :) Embedded Linux is certainly in existence, and it is certainly popular for a wide range of "industrial control applications".

I will just state that many applications that deal primarily with responding to and controlling industrial-level interfaces (digital I/Os, solenoids, relays, serial rs232/485, analog I/Os) also do not overlap with environments that could really leverage the heavy multitasking or other system services offered by Linux.

Reply to
Chon Tang

Care to explain why I answer sales inquiries and support questions all day from our huge list of Linux users? I'm a driver developer for a PC/104 company (Diamond Systems) and according to our support poll,

50% of our users are currently implementing projects in Linux. Rare? Maybe when I started at the company a few years ago, but not anymore.

P.S. Since I'm battling Linux FUD I might as well pitch our products as well. :-)

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We have excellent Linux drivers for all our DAQ products.

Reply to
Nick Popoff

Correct me if I am wrong, but I believe PC104 systems only have the equivalent of ISA interfaces, with no PCI, AGP, USB, etc. Thus your products and drivers are not useful for the cheapest of hardware, the common PC.

Please don't take this as a criticism. I applaud your efforts.

--
Chuck F (cbfalconer@yahoo.com) (cbfalconer@worldnet.att.net)
   Available for consulting/temporary embedded and systems.
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Reply to
CBFalconer

Right! PC/104 really is orthogonal to the consumer PC market. You wouldn't ever want to buy a PC/104 audio board to add to your Athlon consumer PC, or the reverse.

While the PC/104 expansion bus is ISA, this doesn't stop the CPU board in the PC/104 stack from having all kinds of integrated devices like USB, AC'97 audio, AGP 3D video, etc so usually you already have most of the non-ISA features you need right on the embedded CPU board.

The PC/104 market is quite different from the consumer PC solutions market. If the project requirements call for a cheap, small computer then there are plenty of "common PC" solutions out there. However, PC/104 is great when you need extended temperature ranges, vibration tolerance, stackability in tight spaces, low power, big MTBF numbers, lots of vendors selling compatable modules you can stack, extended availability of "legacy" products, etc.

Your typical Athlon motherboard wont last very long if you launch it into space, put it in a military vehicle, monitor oil pumps in the Arctic circle, or try to buy more *exactly* like it 3 years later because thats the only one the FDA certified for use in your medical equipment. It'll fail at +70C, the vibration will knock the RAM right out of the DIMM slots during launch, and Asus US sales will have stopped making that mobo years ago... :-)

Hmm, I think this has gone a bit off topic. Sorry. Reply via e-mail if interested in discussing further.

Reply to
Nick Popoff

What about using one ore several very small integrated processor(s) (e.g. Ubicom 2022 some $10) to do the hardware I/O and connecting them via Ethernet.

-Michael

Reply to
Michael Schnell

That's not true IMHO. I know that there are many projects moving from VxWorks to Linux.

-Michael

Reply to
Michael Schnell

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