Probelm regarding USB-USB connection

texas11960

Prodigy 130 points

Other Parts Discussed in Thread: TUSB3410

I have developed data acquisition system using TMS320VC5509 DSP which has embedded USB slave port.

Now i want to transmit the acquired data on RS-485 network .

So there is requirement of TUSB3410 which converts USB data to RS-485 .

But problem is that how to connect both USB conncections since there isn't any USB host.

So please provide me some solution for this connection..

over 15 years ago

0 Sid over 15 years ago

Genius 4530 points

Hi texas,

Not sure if TI has any product for USB slave-to-slave communication, but Cypress semiconductors has a USB controller by the name of CY76C7300 which can take data from a USB slave device and transfer it to another slave device.

See if it helps.

Regards,

Sid

0 DHarmon over 15 years ago

TI__Genius 16430 points

Texas,

USB is a host centric bus, as such you can not have a USB system (communication) without having a USB host. I am not a C55xx expert, but I would think you could use the serial port on it to talk directly to a RS485 port and not even use the USb port on the DSP.

0 DHarmon over 15 years ago in reply to Sid

TI__Genius 16430 points

The Cypress device you reference here is a USB host device.

Like any USB host, it allows for peripheral connections. It is not a standard PCI-based host, but rather an embedded host which has a generic parallel interface for connection to an application processor. It requires software drivers to facilitate USB peripheral connections - just like any USB host.

That said, TI does not have and standard PCI-based hosts or multi-port embedded hosts available.

Regards

0 texas11960 over 15 years ago in reply to DHarmon

Prodigy 130 points

Actually tms320vc5509 have SPI port and it don't have any UART port for communication so i don't know how to communicate to RS-485 using SPI port ...

For usb-usb connection , can't i use USB OTG ic ?

0 Frank Minich over 15 years ago in reply to texas11960

TI__Expert 4160 points

Possibly you could you use something like Maxim MAX3140: SPI on one side, RS485 on the other.

Using USB OTG seems more complex, especially if the protocol on the RS485 network already exists.

0 DHarmon over 15 years ago in reply to texas11960

TI__Genius 16430 points

USB OTG still requires a device to act as the "host" - granted it is as a limited function host, but it is still a host that involves ptotentially software, drivers, etc. USB is by definition a more complex, higher level protocol bus than RS485.

0 DMLMAX over 15 years ago

Prodigy 30 points

You can find USB to RS485 products, converters and explanations at http://www.usconverters.com

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Probelm regarding USB-USB connection