USB programming?

[Laura]

Hi,

I know absolutely nothing about dealing with hardware input, but want to
get a foot in the door of dealing with incoming USB data (ultimately for
monitoring the input from a hardware measuring instrument).

As a most basic example how would I monitor the data coming from the
Apple usb mouse for instance?
Is there a utility that can monitor data arrving at the ports in realtime?

Presumably, usb data arriving in the computer has ID, header, and value
bytes so that the device software recognises the data as theirs?

As I say, I know nothing about USB input, but want to get a handle on
how to code for it. Any basic, basic, reference sources would also be
appreciated.

Are there CW libraries for handling incoming data?

Thanks

Laura


P.S. For OSX

[David Phillip Oster]

In article <bkut6t$iio$2@hercules.btinternet.com>,
Laura <nospam_lbassett@bigfoot.com> wrote:

> I know absolutely nothing about dealing with hardware input, but want to
> get a foot in the door of dealing with incoming USB data (ultimately for
> monitoring the input from a hardware measuring instrument).
>
> As a most basic example how would I monitor the data coming from the
> Apple usb mouse for instance?
> Is there a utility that can monitor data arrving at the ports in realtime?
>
> Presumably, usb data arriving in the computer has ID, header, and value
> bytes so that the device software recognises the data as theirs?
>
> As I say, I know nothing about USB input, but want to get a handle on
> how to code for it. Any basic, basic, reference sources would also be
> appreciated.
>
> Are there CW libraries for handling incoming data?

Go to Apple's developer web site, download the USB Driver Development
Kit (DDK), and start reading!

[Michael Milvich]

Hello Laura,

You should take a look at
[url]http://developer.apple.com/documentation/DeviceDrivers/Conceptual/USBBook/index.html[/url]

It will walk you through finding a USB device and downloading data to
it. It should be easy enough to modify it to read from the device
instead.

Michael

Laura <nospam_lbassett@bigfoot.com> wrote in message news:<bkut6t$iio$2@hercules.btinternet.com>...

> Hi,
>
> I know absolutely nothing about dealing with hardware input, but want to
> get a foot in the door of dealing with incoming USB data (ultimately for
> monitoring the input from a hardware measuring instrument).
>
> As a most basic example how would I monitor the data coming from the
> Apple usb mouse for instance?
> Is there a utility that can monitor data arrving at the ports in realtime?
>
> Presumably, usb data arriving in the computer has ID, header, and value
> bytes so that the device software recognises the data as theirs?
>
> As I say, I know nothing about USB input, but want to get a handle on
> how to code for it. Any basic, basic, reference sources would also be
> appreciated.
>
> Are there CW libraries for handling incoming data?
>
> Thanks
>
> Laura

>
>
> P.S. For OSX

[Peter Ammon]

Laura wrote:

> Hi,
>
> I know absolutely nothing about dealing with hardware input, but want to
> get a foot in the door of dealing with incoming USB data (ultimately for
> monitoring the input from a hardware measuring instrument).
>
> As a most basic example how would I monitor the data coming from the
> Apple usb mouse for instance?
> Is there a utility that can monitor data arrving at the ports in realtime?
>
> Presumably, usb data arriving in the computer has ID, header, and value
> bytes so that the device software recognises the data as theirs?
>
> As I say, I know nothing about USB input, but want to get a handle on
> how to code for it. Any basic, basic, reference sources would also be
> appreciated.
>
> Are there CW libraries for handling incoming data?
>
> Thanks
>
> Laura
>
>
> P.S. For OSX
>

A lot of people are going to suggest that you write a driver. However,
there is a potentially easier alternative, which is talking to the
hardware from outside the kernel. The advantage of this is that you
won't need to worry about wiring memory, causing a kernel panic, loading
KEXTs, using kernel safe calls, etc.

The disadvantage is that the result will be an application, not a
driver, so the user will only be able to interact with the device
through your application. So a mouse isn't a good example.

See
<http://developer.apple.com/documentation/DeviceDrivers/Conceptual/USBBook/USBDeviceInterfaces/index.html>
for a discussion of how to go about this.

-Peter

[Laura]

Thanks for the help and the link.

Laura


Peter Ammon wrote:

> Laura wrote:
>

>> Hi,
>>
>> I know absolutely nothing about dealing with hardware input, but want
>> to get a foot in the door of dealing with incoming USB data
>> (ultimately for monitoring the input from a hardware measuring
>> instrument).
>>
>> As a most basic example how would I monitor the data coming from the
>> Apple usb mouse for instance?
>> Is there a utility that can monitor data arrving at the ports in
>> realtime?
>>
>> Presumably, usb data arriving in the computer has ID, header, and
>> value bytes so that the device software recognises the data as theirs?
>>
>> As I say, I know nothing about USB input, but want to get a handle on
>> how to code for it. Any basic, basic, reference sources would also be
>> appreciated.
>>
>> Are there CW libraries for handling incoming data?
>>
>> Thanks
>>
>> Laura
>>
>>
>> P.S. For OSX
>>

>
> A lot of people are going to suggest that you write a driver. However,
> there is a potentially easier alternative, which is talking to the
> hardware from outside the kernel. The advantage of this is that you
> won't need to worry about wiring memory, causing a kernel panic, loading
> KEXTs, using kernel safe calls, etc.
>
> The disadvantage is that the result will be an application, not a
> driver, so the user will only be able to interact with the device
> through your application. So a mouse isn't a good example.
>
> See
> <http://developer.apple.com/documentation/DeviceDrivers/Conceptual/USBBook/USBDeviceInterfaces/index.html>
> for a discussion of how to go about this.
>
> -Peter
>