USB: FTDI chip or HID?

[Marco Trapanese]

Hello,

I need to design a board which should send data to a computer via USB.
The data is composed of a packet of about 25/30 bytes sent every 10 ms.
A software running on the PC side should receive this information and
store it on a file.

I'm wondering if it's better to use an FTDI chip and make the things
easy using a virtual COM port or to implement a "true" USB communication
(HID?).

I'm afraid about the speed needed to receive and save the string into a
file.

What do you recommend?
Marco

 

[Tim Williams]

http://www.obdev.at/products/vusb/index.html

Tim

 

[Martin Riddle]

Hello,

I need to design a board which should send data to a computer via USB.
The data is composed of a packet of about 25/30 bytes sent every 10
ms. A software running on the PC side should receive this information
and store it on a file.

I'm wondering if it's better to use an FTDI chip and make the things
easy using a virtual COM port or to implement a "true" USB
communication (HID?).

I'm afraid about the speed needed to receive and save the string into
a file.

What do you recommend?
Marco

FTDI chip, Then you don't need a PID and VID since its in the FTDI
already.
<http://www.ftdichip.com/Support/Doc...tomising_FTDI_VID_PID_In_Linux(FT_000081).pdf>

Cheers

 

[Marco Trapanese]

Il 17/10/2010 23:57, David Brown ha scritto:

What makes you think that a virtual COM port with an FTDI chip is not
"true" USB communication?

The "other end". On the pc side if I use a virtual COM port I need to
receive data from it.
I was thinking that a custom driver that get data directly from a USB
class could be faster.

HID is a USB class, and makes sense if you are making a mouse or a
keyboard, or something that will act like a mouse or keyboard. It
certainly does not sound like that's what you are doing.

You're right. I used HID to make my own joystick controller, but I saw
people that use HID to exchange data.

A virtual COM port (using FTDI chips, or some other kind) is almost
certainly the easiest solution. You can pretend the FTDI chip is just an
RS-232 driver - you connect to it with a UART, and at the other end
you've got a new comms port on the computer. It works with any system
(plug and play on Linux, or by installing FTDI's drivers on Windows),
and you can use a whole range of baud rates up to about 3 MBaud.

Ok, I got it.
I thank all other guys who answered me.

Marco

 

[Marco Trapanese]

Il 17/10/2010 23:43, Tim Williams ha scritto:

http://www.obdev.at/products/vusb/index.html

*Very* interesting!

Thanks!
Marco

 

[Jamie]

Il 17/10/2010 23:57, David Brown ha scritto:




The "other end". On the pc side if I use a virtual COM port I need to
receive data from it.
I was thinking that a custom driver that get data directly from a USB
class could be faster.





You're right. I used HID to make my own joystick controller, but I saw
people that use HID to exchange data.





Ok, I got it.
I thank all other guys who answered me.

Marco

http://www.saelig.com/pr/quickusbmodule.html

Have a look at that..