USB oscilloscope / Signal Generator WAS Re: [TLUG]: Where can I buy a linux-friendly laptop?

[phiscock-g851W1bGYuGnS0EtXVNi6w at public.gmane.org]

Chris -

Thanks for the positive remarks. These days I'm carrying both the scope
and signal generator in my laptop case, along with some demo circuitry.

More at the December 13th TLUG meeting, if you are still in town.

BTW, your letter was mailed today from Vancouver.

Cheers -
Peter



> Where do I sign up for beta testing ? ;-D
>
> This is exactly what an electrical engineer needs if he or she is about
> to sell all of his or her personal belongings & move to a different
> country for a few years :)
>
> What are the dimensions of the device ? Does it fit nice & snug in a
> laptop carrying case ?
>
> ~/Chris
>
> ______________________________
> Christopher Friedt
> Ryerson University
> Computing & Communication Services
> (416) 979-5000 x6831
> chfriedt-0jnyayh6ARPqzrOJbVgLALDks+cytr/Z at public.gmane.org
>
>>>> phiscock-g851W1bGYuGnS0EtXVNi6w at public.gmane.org 11/21/05 10:19:06 pm >>>
>
> (This is a bit of a preview to the TLUG talk on December 13th, in
> which
> we'll demonstrate new oscilloscope and signal generator hardware using
> a
> usb-serial device.)
>
> In general, the usb-serial ports appear as /dev/ttyUSB0, /dev/ttyUSB1
> and
> so on. You simply direct your software to write to that 'serial port'
> as
> it would to any serial port.
>
> Now, when you first plug in a USB-serial adaptor, the system allocates
> one
> of these /dev/ttyUSBx devices to it. This is not like a hardware
> serial
> port, for which the device designation is fixed. The system sees which
> /dev/ttyUSBx device is available and allocates that, regardless of
> which
> hardware USB port you plug in to.
>
> Thereafter (if you are lucky ;) the system remembers that particular
> device  and tries to allocate the same pseudo-serial port as
> previously.
> Obviously this isn't foolproof - if you have two devices that
> previously
> got /dev/ttyUSB1 and you plug them both in at once, the system gets
> confused and you have to select the ports manually.
>
> You can see this at work by running 'dmesg' each time you plug and
> unplug
> the USB-serial cable. It tells you which port it's allocating to the
> device. There is also a program 'usbview' which shows how the usb
> system
> is configured.
>
> We figured this out by trial and error, not by reverse engineering
> code,
> so additional or different information may apply...
>
> So to answer William's question, I would bet that you link /dev/modem
> to
> one of these pseudo-serial ports.
>
> Peter
>
>> If anyone used USB modem successfully, what device do I
>> link /dev/modem to?
>>
>> --
>> William Park <opengeometry-FFYn/CNdgSA at public.gmane.org>, Toronto, Canada
>> ThinFlash: Linux thin-client on USB key (flash) drive
>> 	   http://home.eol.ca/~parkw/thinflash.html
>> BashDiff: Super Bash shell
>> 	  http://freshmeat.net/projects/bashdiff/
>> --
>> The Toronto Linux Users Group.      Meetings: http://tlug.ss.org
>> TLUG requests: Linux topics, No HTML, wrap text below 80 columns
>> How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml
>>
>
>
> --
> Peter Hiscocks
> Professor Emeritus,
> Electrical and Computer Engineering,
> Ryerson University
> 416-465-3007
> www.ee.ryerson.ca/~phiscock
>
> --
> The Toronto Linux Users Group.      Meetings: http://tlug.ss.org
> TLUG requests: Linux topics, No HTML, wrap text below 80 columns
> How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml
> --
> The Toronto Linux Users Group.      Meetings: http://tlug.ss.org
> TLUG requests: Linux topics, No HTML, wrap text below 80 columns
> How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml
>


-- 
Peter Hiscocks
Professor Emeritus,
Electrical and Computer Engineering,
Ryerson University
416-465-3007
www.ee.ryerson.ca/~phiscock

--
The Toronto Linux Users Group.      Meetings: http://tlug.ss.org
TLUG requests: Linux topics, No HTML, wrap text below 80 columns
How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml