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Topic: Basic Usage Questions: FT2232 breakout board (Read 15506 times) previous topic - next topic

Basic Usage Questions: FT2232 breakout board

Hello,

In my case I was thinking of embeding the FT2232 breakout board into my project once I verified the basics.  This project will be a one off device.  I have two serial devices I want to interface to USB.

I am thinking that with the one USB connector on the breakout board that the two serial interfaces are joined and the USB connector provides them multiplexed.  Not sure if this is done like a usb hub or through some other mechanism.  Any insight would be appreciated.

Also, any reason the USB pins can't also be exposed on a header?  This would aide in my case but I understand that what I want to do might be "abusing" the intended use.

Alternately I can just incorporate FTDI chip(s) directly as I think I don't need all the support circuitry this breakout provides.

Thanks,

John

Re: Basic Usage Questions: FT2232 breakout board

Reply #1
the 2 serial ports are what ftdi chip exposes. The 2232h is a high speed usb2.0 device so there's 60MHz communication between chip and your computer, more then enough for 2 serial ports :D. 2232H has 2 cores so it will be seen on your PC as 2 devices. You can configure it for maximum high speed 245 mode where it utilizes only one channel to send 60MHz data stream.

Any USB device can publish as many "targets" as it wants and each "target" can be a separate usb entity (CDC, MASS STORAGE, Printer, video, audio ...)

Re: Basic Usage Questions: FT2232 breakout board

Reply #2
what arhi said :)..
USB pins weren't broken out to keep the d+ and d- line clean, as this is a 480mhz device...they probably could have been since, motherboard use simple cabling and even simpler PCBs for the front panel ports...But I guess we just wanted to be safe, that the device works 100%...

as a work around you could cut-open a usb cable and have access to d+/d- lines, or even better, use our design files to simply add breakouts...and get pcbs manufactured cheaply trough seeed, or ittead
best regards FIlip.

Re: Basic Usage Questions: FT2232 breakout board

Reply #3
cases use shielded cables with precise impedance to avoid ringing .. it's not 2 wire flying around the case :D (it is in some el cheapo hung low cases but those broken out connectors don't run at high speed). If you look at brackets with usb that come with mid/hi end motherboards you will notice they have thick cable that's not that easy to bend .. I would not call that "simple"

If you break out pins for the usb and not follow strict rules it wont work at high speed (did that, had issues, it's enough to have ground cut one of the data lines for speed to be cut back)

Re: Basic Usage Questions: FT2232 breakout board

Reply #4
Thanks all for the quick and detailed responses!

Re: Basic Usage Questions: FT2232 breakout board

Reply #5
[quote author="arhi"]cases use shielded cables with precise impedance to avoid ringing .. it's not 2 wire flying around the case :D (it is in some el cheapo hung low cases but those broken out connectors don't run at high speed). If you look at brackets with usb that come with mid/hi end motherboards you will notice they have thick cable that's not that easy to bend .. I would not call that "simple"

If you break out pins for the usb and not follow strict rules it wont work at high speed (did that, had issues, it's enough to have ground cut one of the data lines for speed to be cut back)[/quote]

I was talking about the el cheapo hung low cases :D
best regards FIlip.

Re: Basic Usage Questions: FT2232 breakout board

Reply #6
Hi Ahri,

Please excuse me if this is slightly off-topic,
but I have been searching around on the web to find any information
on how to set up an FTDI FT2232C so that it appears as an audio device to the PC
(or whatever is talking to it via usb.

Could you give me a pointer to how that can be done, or where I can find more info on this?

Many thanks!

Re: Basic Usage Questions: FT2232 breakout board

Reply #7
[quote author="ejp62"]
on how to set up an FTDI FT2232C so that it appears as an audio device to the PC
(or whatever is talking to it via usb.
[/quote]

you don't. FTDI chips can use 2 types of drivers as explained on the ftdi site.
You can use VCP drivers and that will give you Virtual Com Port and you can use D2XX drivers that won't give you "anything" but will allow you to talk to chip directly. When you see your ftdi chip directly (so you can put it in any mode chip allows, single channel, dual channel, serial, parallel, ft245, i2c, spi... turn pins on/off..) then you can implement on the software side whatever driver you want that will use this D2XX driver. You can either create a system audio driver that will connect to your device or you can create some stand alone app that will directly talk to your device, in any way you have to do it trough D2XX. There is no "usb audio" protocol that FTDI understands.

so for example to have a 30MHz 16bit DAC, you send 30MHz 16 bit data directly to ft2232h via D2XX driver and on the 16 output pins + sync pin of the ft2232h you connect your r2r ladder and your amp.


Re: Basic Usage Questions: FT2232 breakout board

Reply #9
Hi Arhi,

Many thanks for your quick reply! I avoid using Win#@$ also, so that´s fully undrstood.
I had hoped that an FTDI device could be setup to show up as a generic audio device,
such that it would be recognized by all kinds of devices (media streamers and such)
as something that accepts an audio stream using a standard driver on the streamer side.
I guess that will not be possible!

EJ

Re: Basic Usage Questions: FT2232 breakout board

Reply #10
I'm not sure that generic audio device exist at all .. it's all about drivers, ftdi will present vid/pid that you configure in it, your os will call up the usb driver for that vid/pid and whatever that driver say it's the device - that's what it will be .. so if your driver decide to talk to user space trough /dev/dsp# or /dev/audio# it will be a sound device, if it talk trough /dev/hid# or /dev/tty* or ... you get the idea. the "generic" is just a compatible device with pre-existing driver in the os

Re: Basic Usage Questions: FT2232 breakout board

Reply #11
Hijacking this thread a bit.

The ft2232 board is suppoesedly useful for jtag, but how to connect it to do jtag thingy ?, say for urJtag?
which pins are for jtag use on this board?

Re: Basic Usage Questions: FT2232 breakout board

Reply #12
[quote author="neslekkim"]Hijacking this thread a bit.

The ft2232 board is suppoesedly useful for jtag, but how to connect it to do jtag thingy ?, say for urJtag?
which pins are for jtag use on this board?[/quote]

for e.g.: http://www.ethernut.de/pdf/turtelizer20c-schematic.pdf

Re: Basic Usage Questions: FT2232 breakout board

Reply #13
damn, that was lot of parts involved, so I cannot just connect the ft2232 to an jtag port then?
Ok, lets hope that usb blaster/altera clone come fast.. (riglol memory dumping.. )