usbfs design question

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Anonymous
Not applicable

Hi,

   

I am considering the design of an interface device (board) that essentially will make multiple USB devices appear as one USB device. 

   

Just a bit of back ground.  I am an amateur radio operator and use a radio called the Peaberry V2.  I own multiple of these radios.  Currently each radio attaches to a PC via USB.  Each radio appears as a separate device on the PC.  Each radio has a operates on a unique band of frequencies.  Currently the PC host application needs to be stopped, reconfigured and restarted to switch between radios.  The idea is to use a PSoC 3 and configure multiple USBFS components (one for each radio) and then select a given USBFS component and route the data to a common USBFS component that is attached to the PC.  

   

The interface device will do more than USB interfacing but I would like to know what folks think about this aspect first. 

   

I need to stay with the PSoC 3 as this is the only chip that is available in a 48 pin configuration.  The board will be offered as kit and the 48 pin version is the only chip that can be reasonably be soldered into place by a kit builder

   

Thanks for taking a look,

   

Ron

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ETRO_SSN583
Level 9
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You might contact local sales office or manufacturers rep

   

to confirm that specific part will be around for awhile, and

   

how long.

   

 

   

Just a thought.

   

 

   

Regards, Dana.

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Anonymous
Not applicable

Hi Dana,

   

I will do that.  That would be a bummer if the 48 pin version has a near term end of life.  The alternative is to have whatever company does the PCB fabrication install the PSoC.  But that would raise the cost of the kit and a lot of hams run a very thin budget

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ETRO_SSN583
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The USBFS is a fixed function block, and only one allowed

   

to be instantiated. You might have to talk to a hub to accomplish

   

what you want.

   

 

   

Or look at multilane Cypress parts, or the upcoming low cost PSOC 4 L

   

series (1 lane/).

   

 

   

    

   

          http://www.cypress.com/?docID=49335

   

 

   

Regards, Dana.

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Anonymous
Not applicable

Thanks again, Dana.

   

I would have been chasing my tail.   So, just for my education, what exactly is a fix function block?  And why only one instance?

   

Thanks,

   

Ron

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ETRO_SSN583
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There are two main types of resources on PSOC,

   

FF and UDB. The FF blocks are optimized HW,

   

whereas the UDB much more programmable

   

and general purpose. So a UDB can take on many

   

personalities, but sacrifices optimal properties.

   

 

   

The basic idea is to equip a part with commonly used, highly

   

optimized capabilties, like COM and basic counter.... and use the

   

UDB for design specific purposes and or more features than

   

most commonly used types of HW.

   

 

   

So a UDB counter, or PWM, has many more features than a

   

FF one. Whenever possible one should use up the FF resources

   

on chip if features adequate, then proceed to using UDB. Some

   

functions only come in UDB however.

   

 

   

The inevitable tradeoffs one makes in chip and product design.

   

 

   

One instance, I would posit the USB transceiver, its power requirements,

   

limited the number of USB channels.

   

 

   

Regards, Dana.

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