FX3 Usb Boot Mode

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Anonymous
Not applicable

Hello,

   

I'm confused about FX3's boot mode.
As I understand from FX3 Programmers Manual page 42, FX3's firmware and VID/PID/DID can be change over USB cable without using an eeprom thorough renumeration process.

   

If I understand right, then why an eeprom is needed for a host connected (via USB cable) FX3 system?

   

What can't be done with usb boot mode in USB connected FX3 system?

   

Regards,

   

Ali

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11 Replies
RoKl_290166
Level 4
Level 4
Welcome!

Hi Ali,

   

check the application note describing FX3's boot via USB: http://www.cypress.com/?rID=56486

   

It contains the answers to your questions!

   

 

   

Regards,

   

Rob

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Anonymous
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Hi Rob,

When I reread the application note, "USB with VID/PID Options" title got my attention. As I understand from the title, there is a three source to change VID/PID that are I2C eeprom, SPI eeprom and efuse. The efuse seems like custom manufacturing which is not a preferred way.

   

Therefore without using an eeprom or efuse process, VID/PID can't be changed. Am I right?

Regards,
Ali

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Anonymous
Not applicable

The VID/PID option being spoken about is to change just the VID/PID of the device (no firmware).

   

 

   

With USB boot as well you'll be able to change VID/PID i.e. by downloading entire firmware and have firmware handle the descriptor requests. Here is the problem with using the default VID/PID (i.e. using no EEPROM), there is the script download method using which cyusb.sys will download firmware to device bound to it.

   

If 2 different designs use the default VID/PID and script download method then when they're used in the same PC there is a possibility of cross-downloading for firmware. So designs which want to reduce EEPROM size use a small EEPROM just for VID/PID and then this VID/PID is bound to cyusb.sys plus a script file. The script file will have the firmware to be downloaded it will download that and renumerate.

   

Regards,

   

Anand

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Anonymous
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Rob and Anand,

Thanks, I clearly understand the process now.

Regards,
Ali

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Anonymous
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Hello:

   

        Now I am learning usb3.0 and have draw a usb3.0+fpga board.I begin debug,but I encounter a problem.I set PMODE[2:0]=F1F,but I get  PMOD[2:0]=111,why?And I  find  unknow drive(VID=0000,PID=0000),but sometimes I find Cypress USB BootLoader,why?

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I recently went through a lot of debug regarding latching in PMODE[2:0] on the rising edge of reset.

My design required the ability of software to generate a reset after a certain event occurred (insertion of an SDXC card).

When trying to program the SPI flash, the Cypress was detected as a USB Benica device, PMODE[2:0] = 111, when I had it set to FF1.

I was driving the reset pin with an SN74LVC1G08, an AND gate with 32ma, -32mA totem pole outputs. The edge of reset was too fast, and the device was correctly detected as a USB Bootable device only one in ten resets.

I modified my hardware to use an SN74AHV1G09, open drain AND gate and connected a 100K pull up to +3.3V anda 0.1uF apacitor to ground giving me a nice slow reset rise time.

The device is now correctly detected as PMODE[2:0] = FF1 for programming, a 0F1 from normal operation. Have tested thousands of enumerations and not one Benica.

The data sheet does not specify a minimum rise time, only a minimum pulse width which was being vastly exceeded.

Hope this helps someone else.

Richard

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Correction, typo, the open drain AND gate was an SN74AHC1G09DBVR SOT23-5.

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Anonymous
Not applicable

 Did you get a chance to look at this application note:

   

http://www.cypress.com/?rID=53203

   

Regards,

   

sai krishna

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Anonymous
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hello:

   

          I cannot still understand it! Ihope to get specific instruction.

   

regards

   

Alian

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Anonymous
Not applicable

 Alian,

   

Could you please share your board schematics with me. 

   

Did you get them reviewed by any Cypress engineer.

   

Thanks,

   

sai krishna.

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