USB *Host* for VCP?

[st3]

Posted on August 01, 2009 at 14:18

USB *Host* for VCP?

[st3]

Posted on May 17, 2011 at 13:18

Is there a ready example for any of the USB-host equipped parts for a ''virtual com port'' ?

eg, so that it could host a USB-to-serial converter.

I had a quick look at the USB on-the-go (OTG) FS library, but didn't see anything obvious.

The reason is that I want to log data from a device that's intended to plug into a PC's USB port, and appears as a COM port on the PC.

(the device does actually have an FTDI USB-to-UART chip inside)

Using a PC to do the logging is not convenient.

[ This message was edited by: st7 on 28-07-2009 10:14 ]

[ This message was edited by: st7 on 29-07-2009 13:16 ]

[jj_it]

Posted on May 17, 2011 at 13:18

I like your application.

Borrowing from ''your'' past posts - might it be simpler to hack/bypass the FTDI device - and simply communicate Uart to Uart? (USB protocol may disallow - but we have heard of this working in some cases...)

[st3]

Posted on May 17, 2011 at 13:18

Quote:

might it be simpler to hack/bypass the FTDI device - and simply communicate Uart to Uart?

Yes, it would - but that would void my warranty on the device!!

[st3]

Posted on May 17, 2011 at 13:18

Apparently not, then?

:(

But this looks like just what I'm after:

http://www.ghielectronics.com/products

It uses an NXP

http://www.nxp.com/pip/LPC2388_1.html

- ARM7 with 512 kB flash with ISP/IAP, Ethernet, USB 2.0 device/host/OTG, CAN, and 10-bit ADC/DAC

NXP said:

Quote:

The LPC2388 is ideal for multi-purpose serial communication applications.

Sounds ideal, then!

Unless someone can suggest an STM32 alternative...

[st3]

Posted on May 17, 2011 at 13:18

No, the device is a diagnostic interface to other equipment.

Eventually the aim is to implement the full interface, but for now I just want some quick and simple way to capture the data from this 3rd party device.

If the UART interface were accessible, it'd be simple...

But it strikes me that UART/RS232 interfaces are becoming rapidly rarer - so the need for this kind of thing can only increase...

[jj_it]

Posted on May 17, 2011 at 13:18

From my read/recall of your posts perhaps you could use STM32 (with the possible addition of a higher res. ADC) and eliminate the acquisition/logger device all together. Completely agree with you that use of PC is often inconvenient/overkill...

[st3]

Posted on May 17, 2011 at 13:18

Quote:

We already provide a CDC Virtual Com Port Example

But that's a CDC device, isn't it - not a *Host*.

I am specifically after a *Host* :-W

Quote:

Hope this helps you.

Not in the least, I'm afraid.

[ This message was edited by: st7 on 31-07-2009 23:01 ]

[16-32micros]

Posted on May 17, 2011 at 13:18

Hi,

We already provide a CDC Virtual Com Port Example in our pages, refer to

Example Virtual Com Port :

http://www.st.com/stonline/products/support/micro/files/um0424.zip

http://www.st.com/stonline/products/literature/um/13465.pdf

Hope this helps you. Cheers,

STOne-32.

[st3]

Posted on May 17, 2011 at 13:18

It appears that Atmel managed do it a couple of years ago for the 8-bit AVR:

Atmel wrote:

Quote:

AVR280 USB Host CDC Demonstration (Application Note, 14 pages, revision A, updated 09/07)

The aim of this document is to describe how to start and implement a Host CDC application using the STK525 or USBKEY starter kit, and finally introduces a simple example of dual USB-UART bridge between two PCs.

See:

http://www.atmel.com/dyn/resources/prod_documents/doc7727.pdf

So, surely, ST must be able to come up with something equivalent for an STM32... :o

[16-32micros]

Posted on May 17, 2011 at 13:18

Hi st7,

Regarding USB Host and OTG stacks for the STM32 Connectivity Line, we are working with many partners and third parties to give you the choice for your application requirements and preferred partners :

HCC-Embedded:

HCC's EUSBH (Embedded USB Host Stack) is a full-featured host stack designed for embedded applications

IAR :

PowerPac , USB Host, Add-on option to IAR PowerPac for ARM. It implements full USB host functionality and enables developers to easily add this functionality to embedded systems.

Micrium :

µC/USB-Host is a compact, reliable USB host stack. Built to be portable, scalable and robust, µC/USB-Host enables the rapid integration of support for connection of USB devices to your embedded system, thereby minimizing your time to market.

Micro Digital :

smxUSBH host stack permits connecting USB devices, such as USB thumb drives, USB printers, and USB HIDs (Human Interface Devices) to embedded units

Quadros Systems :

The RTXCusb host system has been developed specifically to support the unique requirements of USB host implementation in embedded systems. This powerful solution complies with the USB Implementers Forum requirements for Embedded Hosts

Segger :

Segger’s USB host software stack implements full USB host functionality, including external hub support, and optionally provides device class drivers. It enables developers to easily add USB host functionality to embedded systems

and also others are coming.

Cheers,

STOne-32.