[Wiltshire] DAQ // Comedi under Linux

[Simon Fryer]

I was going to say something along the lines of what Ben has just
said. The SCADA system I work on is a Windows platform, even a lot of
the RTUs.

For actual analogue to digital conversion, Wago seem to produce a
comprehensive series of bricks that do most industrial sensing to most
widely implemented control interfaces. If I had deep pockets, or had
something someone else had to support it would be Wago. Check out the
Farnell web site.

If I am doing it for fun (a project I am planning at the moment), then
I would be using an AVR (or PIC) talking Modbus over serial to the
host PC/server.

Simon.

2009/9/25 Ben <BenAtNoFixedAbode at lineone.net>:
> Not that exactly but I have done that sort of thing on Windows and been
> associated with Linux SCADA projects at work.
>
> TBH the last time I put a measurement card into a computer was
> approximately18 years ago.  We tend to add external hardware that is
> accessed either by a serial port (RS232 or RS422 or RS485) or more
> commonly today ethernet.
>
> Normally you just have to implement some fairly simple communications
> protocol (e.g. MODBUS).
>
> Obviously you have to be able to afford the external hardware, did you
> have a budget in mind?
>
> There are a couple of modules I used recently at work, one is ADAM I
> can't remember the other.
>
> Let us know if you would like more detail.
>
> Cheers
> Ben
>
> Simon Iremonger wrote:
>> Has anybody out there had any success with any forms of DAQ
>>    modules, ADC into linux (e.g.. via comedi driver in kernel)?
>>
>> I want to make accurate measurements/graphs of modulation from
>>    different sorts of light using a photodiode and computer,
>>    preferably from portable pc without full-size-PCI!
>>
>> I was just wondering if anybody has done this!
>>
>> I'ts possible to get things like the 'linux-usb-daq', I just
>>    wondered if anybody had succeeded with getting cheap cards
>>    from anywhere and running xoscope on linux etc.
>>
>>
>> Thanks,
>>
>> --Simon <wiltslug at iremonger.me.uk>

-- 
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