LinuxLists.cc - [Bluez-devel] HCI data packet

2005-08-24 09:58:01

Subject: [Bluez-devel] HCI data packet

Hello you all

I have been reviewing BlueZ code and Bluetooth specification, and have found
a doubt related with HCI data packets. They are supposed to be used to
exchange data between Host and Host Controller, and the Connection Handle
field addresses the connection from one BT device to another. But, how is
this connection handle assigned? Can it be used to directly send data from
one device to another by using HCI?

(I was wondering, if I can exchange data between devices directly through
HCI, by using HCI socket opened by the function hci_open_dev, and how can it
be done)

Thank you very much for your help!!

Esther

2005-08-25 16:45:02

by Esther López Casariego

[permalink] [raw]

Subject: RE: [Bluez-devel] HCI data packet

Hi Marcel

> -----Mensaje original-----
> De: [email protected] [mailto:bluez-devel-
> [email protected]] En nombre de Marcel Holtmann
> Enviado el: mi=E9rcoles, 24 de agosto de 2005 17:14
> Para: [email protected]
> Asunto: RE: [Bluez-devel] HCI data packet
>=20
> Hi Esther,
>=20
> > Regarding the HCI data packets... What is the maximum size of the =
data
> > field? Is if fixed or can be set by the BlueZ user?
>=20
> this depends on the ACL and SCO MTU sizes.
>=20
Thanks again for your help. I have been investigating and found that the =
ACL
and MTU sizes are fixed by the manufacturer. Is there any typical or =
maximum
value for them? I have here 2 USB dongle, and both have 192 bytes.

Thanks, and regards

Esther

> Regards
>=20
> Marcel
>=20
>=20
>=20
>=20
> -------------------------------------------------------
> SF.Net email is Sponsored by the Better Software Conference & EXPO
> September 19-22, 2005 * San Francisco, CA * Development Lifecycle
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http://www.sqe.com/bsce5sf
> _______________________________________________
> Bluez-devel mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/bluez-devel

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2005-08-24 15:14:24

by Marcel Holtmann

[permalink] [raw]

Subject: RE: [Bluez-devel] HCI data packet

Hi Esther,

> Regarding the HCI data packets... What is the maximum size of the data
> field? Is if fixed or can be set by the BlueZ user?

this depends on the ACL and SCO MTU sizes.

Regards

Marcel

-------------------------------------------------------
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September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices
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Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf
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2005-08-24 14:31:50

by Esther López Casariego

[permalink] [raw]

Subject: RE: [Bluez-devel] HCI data packet

Hi Marcel

Thanks for your help. That is what I was looking for.

Regarding the HCI data packets... What is the maximum size of the data
field? Is if fixed or can be set by the BlueZ user?

Regards

Esther

-----Mensaje original-----
De: [email protected]
[mailto:[email protected]] En nombre de Marcel
Holtmann
Enviado el: mi=E9rcoles, 24 de agosto de 2005 12:01
Para: [email protected]
Asunto: Re: [Bluez-devel] HCI data packet

Hi Ester,

>=20
> I have been reviewing BlueZ code and Bluetooth specification, and have
> found a doubt related with HCI data packets. They are supposed to be
> used to exchange data between Host and Host Controller, and the
> Connection Handle field addresses the connection from one BT device to
> another. But, how is this connection handle assigned? Can it be used
> to directly send data from one device to another by using HCI?=20

the ACL packet handle is assigned by the connect_complete event and you
can find any details about it in the HCI part of the core specification.

Regards

Marcel

-------------------------------------------------------
SF.Net email is Sponsored by the Better Software Conference & EXPO
September 19-22, 2005 * San Francisco, CA * Development Lifecycle =
Practices
Agile & Plan-Driven Development * Managing Projects & Teams * Testing & =
QA
Security * Process Improvement & Measurement * =
http://www.sqe.com/bsce5sf
_______________________________________________
Bluez-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/bluez-devel

-------------------------------------------------------
SF.Net email is Sponsored by the Better Software Conference & EXPO
September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices
Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA
Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf
_______________________________________________
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[email protected]
https://lists.sourceforge.net/lists/listinfo/bluez-devel

2005-08-24 10:01:06

by Marcel Holtmann

[permalink] [raw]

Subject: Re: [Bluez-devel] HCI data packet

Hi Ester,

>
> I have been reviewing BlueZ code and Bluetooth specification, and have
> found a doubt related with HCI data packets. They are supposed to be
> used to exchange data between Host and Host Controller, and the
> Connection Handle field addresses the connection from one BT device to
> another. But, how is this connection handle assigned? Can it be used
> to directly send data from one device to another by using HCI?

the ACL packet handle is assigned by the connect_complete event and you
can find any details about it in the HCI part of the core specification.

Regards

Marcel

-------------------------------------------------------
SF.Net email is Sponsored by the Better Software Conference & EXPO
September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices
Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA
Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf
_______________________________________________
Bluez-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/bluez-devel

2005-09-05 12:00:28

by Marcel Holtmann

[permalink] [raw]

Subject: RE: [Bluez-devel] HCI data packet

Hi Esther,

> Regarding HCI data packets and BlueZ...
>
> If I use the BlueZ command "hci_create_connection" and connect to another
> device, how do I sent an HCI data packet to this device?

you need to use the raw socket for it and then follow the H:4 protocol,
but doing any communication this way is not a good idea. You have to
deal with different packet sizes and handle the ACL-cont flag. Even for
a very simple protocol you should use L2CAP. The overhead of L2CAP is
really not that much.

Regards

Marcel

-------------------------------------------------------
SF.Net email is Sponsored by the Better Software Conference & EXPO
September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices
Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA
Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf
_______________________________________________
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[email protected]
https://lists.sourceforge.net/lists/listinfo/bluez-devel

2005-09-01 14:54:47

by Esther López Casariego

[permalink] [raw]

Subject: RE: [Bluez-devel] HCI data packet

Hello again

Regarding HCI data packets and BlueZ...

If I use the BlueZ command "hci_create_connection" and connect to =
another
device, how do I sent an HCI data packet to this device?

Thanks and Regards

Esther

-----Mensaje original-----
De: [email protected]
[mailto:[email protected]] En nombre de Esther =
Lopez
Enviado el: jueves, 25 de agosto de 2005 18:45
Para: [email protected]
Asunto: RE: [Bluez-devel] HCI data packet

Hi Marcel

> -----Mensaje original-----
> De: [email protected] [mailto:bluez-devel-
> [email protected]] En nombre de Marcel Holtmann
> Enviado el: mi=E9rcoles, 24 de agosto de 2005 17:14
> Para: [email protected]
> Asunto: RE: [Bluez-devel] HCI data packet
>=20
> Hi Esther,
>=20
> > Regarding the HCI data packets... What is the maximum size of the =
data
> > field? Is if fixed or can be set by the BlueZ user?
>=20
> this depends on the ACL and SCO MTU sizes.
>=20
Thanks again for your help. I have been investigating and found that the =
ACL
and MTU sizes are fixed by the manufacturer. Is there any typical or =
maximum
value for them? I have here 2 USB dongle, and both have 192 bytes.

Thanks, and regards

Esther

> Regards
>=20
> Marcel
>=20
>=20
>=20
>=20
> -------------------------------------------------------
> SF.Net email is Sponsored by the Better Software Conference & EXPO
> September 19-22, 2005 * San Francisco, CA * Development Lifecycle
> Practices
> Agile & Plan-Driven Development * Managing Projects & Teams * Testing =
& QA
> Security * Process Improvement & Measurement * =
http://www.sqe.com/bsce5sf
> _______________________________________________
> Bluez-devel mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/bluez-devel

-------------------------------------------------------
SF.Net email is Sponsored by the Better Software Conference & EXPO
September 19-22, 2005 * San Francisco, CA * Development Lifecycle =
Practices
Agile & Plan-Driven Development * Managing Projects & Teams * Testing & =
QA
Security * Process Improvement & Measurement * =
http://www.sqe.com/bsce5sf
_______________________________________________
Bluez-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/bluez-devel

-------------------------------------------------------
SF.Net email is Sponsored by the Better Software Conference & EXPO
September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices
Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA
Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf
_______________________________________________
Bluez-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/bluez-devel

2005-09-01 14:40:17

by Esther López Casariego

[permalink] [raw]