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We make a device which currently connects to the COM ports.
However of late I see COM ports are to be abolished mid-next year.
Does anyone have any info on programming USB???
I see there are hardware converters available to convert COM->USB.
What exactly do these do? Surely software written to address a COM port cannot access a USB in the same manner - so the adaptor is rendered useless???
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The Obliterator
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Actually yeah it does, thanks.
The MS DDK looks promising, though I feel I have a lot of work ahead of me! 
Damn our customers and these ever changing standards! 
I'd seen usb.org but it seemed more orientated to the technical specification rather than what I was after.
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The Obliterator
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Don't ignore Firewire. It's faster than USB and is great for hanging multiple storage devices off a single machine.
1294a was just completed, doubling the speed of Firewire to 960mb.
I believe USB2 is only 400mb or so. Is that correct?
To hell with those thin-skinned pillow-biters. - Me, 10/03/2001
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Yeah, one customer has requested Firewire support... but as its not really supplied as standard on any PCs I would be very reluctant.
Besides I really don't see the need, our device is very low bandwidth (2 bytes every 38ms!)
Unless there are other advantages to Firewire???
Thanks anyhow though.
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The Obliterator
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You mean beyond the fact that it always seems to be significantly faster than USB, or that the standard has been around long enough to be a mature spec, or the fact that you can plug your IDE drives (hard drives, CR-ROMs, CD-R/W's and DVD) into external firewire cases?
Nope, no other benefits...
To hell with those thin-skinned pillow-biters. - Me, 10/03/2001
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>>you can plug your IDE drives (hard drives, CR-ROMs, CD-R/W's and DVD) into external firewire cases?
Is this not the same for USB also??
I agree with the maturity and speed points though.
Problem is I need a solution thats widely available, that people can connect to their laptops, etc. USB seems to fit my needs about the best.
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The Obliterator
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By design, USB has a cable length limit of 5 metres.
You are able to use up to 4 cables extenders to increase the distance to 25 metres, but no futher. So if your device is located more than 25 metres from your computer, USB is not the way to go. As far as I know, Firewire does not have this cable length problem.
My advise is to read the USB specification carefully and make sure the USB is the solution for your device, it does have some very important limitations.
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Thankyou, this was not an issue I was aware of. Though that should be more than adequate for our device.
I have downloaded volumes on the USB specification and look forward to a little light reading!
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The Obliterator
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>> However of late I see COM ports are to be abolished mid-next year
Funniest thing i've heard all day.
Admittedly, today has been a bit slow. But that's utter chud anyway. People still use COM ports for Modems and stuff. And serial connections to telco apparatus. And most POS equipment is RS-232 (tils, receipt printers, barcode readers etc)
Sorry to dissapoint you all with my lack of a witty or poignant signature.
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Well, I hate to be the bearer of bad news, but Intel has publicly stated that they're going to abandon of "legacy device" support within the next year or so. This means bye bye to serial ports, parallel ports, PS/2 mouse ports, keyboard ports, etc.
I guess they want to throw everything onto the USB bus. It would certainly make for more efficient chipsets, but it would also force everyone to update their admittedly aging array of legacy devices. If Intel abandons these ports, you can most assuredly count on Microsoft following suit in subsequent versions of Windows.
To hell with those thin-skinned pillow-biters. - Me, 10/03/2001
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COM ports will be around a LONG LONG LONG LONG time. Might not be available on your standard PC system, but you will always be able to get them as addons.
Too much stuff needs a COM port.
Tim Smith
Descartes Systems Sciences, Inc.
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Yes I would tend to agree... but it makes it difficult to sell our kit if nots easy to use and connect.
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The Obliterator
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I don't find it funny... my day has gone from bad to worse! 
Whilst trawling around for USB info I read an extract from an Intel article clearly stating they plan to withdraw all legacy support. This includes serial, parallel and floppy drives!
They expect all users to use USB compliant devices instead.
Just how you are expected to repair Windows when it all goes pear shaped in the future I have no idea! 
>>Funniest thing i've heard all day.
>>>> However of late I see COM ports are to be abolished mid-next year
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The Obliterator
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FWIW, there are devices that connect to the USB and provide serial ports. I spent a few minutes looking through a PC Connection catalog and I found units from Belkin, Comtrol, Keyspan, Targus, and Tripp-Lite and they do not appear too expensive.
There are also software packages available to help with USB driver development. I think Blue River Systems has one and there are a few others.
Best of luck.
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Yes this was really part of my original question, thankyou.
I couldn't understand how an adaptor would allow the software to work without custom software mapping the USB as some kind of virtual COM port. Clearly this is the case, and I may explore these options as a short term fix. For anyone else with similar problems here is one such solution:
http://catalog.belkin.com/IWCatProductPage.process?Product_ID=66002
As for Blue River Systems, I will have a hunt for their stuff now and see whats on offer. Thanks.
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The Obliterator
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One of my first vc++ applications...
What is the best way to open new windows 'in' an existing child window in a VC++/MFC/MDI application ? (e.g. based on MS VC++ sample 'mdi', with the 'hello' and 'bounce')
My application should open a child window (window_1).
Clicking in window_1 would result in a new child-of-child window inside window_1 (window1_1, window1_2 etc.)
Once that is working, I would like to draw a line between the windows. (e.g. arrow from border of window1_1 to border of window1_2)
If you have any solutions, pointers to code/doc etc. it will make me so very happy !
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float fAngle = atan(1);
what's wrong with this? I don't get any reasonable values out of the atan function! There's nothing wrong with assigning a double to a float is there? Tried this also, gave the same crap:
float fAngle = (double) atan(1);
As far as I know, the outcome of this function is supposed to be 45. Sorry if I come over a bit angry, I am 
I spent half the day trying, so please help
WAVK
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atan accepts a double, and returns a double
try this:
float fAngle = (float)atan(1.0);
although, I would really look into changing the type of fAngle to double.
To hell with those thin-skinned pillow-biters. - Me, 10/03/2001
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I've beenn trying too long and so my stupid head converted a double to a double instead of a float thanks for clearing me up
WAVK
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The result is supposed to be Π/4 because the result is in radians, not in degrees.
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Hi wavk;
atan(1) is 45, as long as 1 is in degrees.
All the trig functions in C are in radians which give you 0.785...
This might be your problem.
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i've recently installed win2k. now, when i use class wizard to add a message handler, when i hit OK, i get a message about how VC was unable to copy this or that temp file, or that the file CW was working on was unable to be written, etc..
has anyone else seen this?
could it be related to NAV?
-c
Smaller Animals Software, Inc.
http://www.smalleranimals.com
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I don't have any problems (not running NAV, though). Are the resource files resource.h and app.res) read-only?
To hell with those thin-skinned pillow-biters. - Me, 10/03/2001
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nope....
it usually happens on the .CPP for the window i'm working on. more than once, it's told me that it can't write the CPP (after adding the new message handler) and that my only chance of recovering the .CPP is to go out and look inside a particular temp file. scary sh*t.
-c
Smaller Animals Software, Inc.
http://www.smalleranimals.com
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