FX3 OTP Bootloader

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GrHa_3282776
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5 replies posted 5 questions asked First reply posted

I am using the CYUSB3014 FX3, I have a custom board designed, and I am having trouble communicating with the PC.  Nothing shows up in device manager, and nothing in Control Center.  I have things setup almost exactly like the Superspeed explorer kit.  I am using USB boot, PMODE[2:0] = Z11, and I have a jumper for I2C boot (Z1Z), once we get the I2C programmed.  The oscillator is operating at 19.19Mhz, FSLC[2:0] are all tied low to configure for 20Mhz.  The Reset pin has a pull up, and is reading 3.3v.  The power rails look good, 5v. 3.3, 1.2.  They are configured just like the explorer board.  I have also tried another 5v supply, I am using both USB 3.0 and 2.0, but my application will only need 2.0.  On the D+ and D- lines I see the pair rise high briefly and decay to 0.  On the explorer board, I see pulse and data every 125us.  I understand the bootloader should be programmed already, is there any other one time programming?  What else to check?

Thanks, Greg

Win 10

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1 Solution

Hello,

VBUS should have typical voltage level of 5V. If this condition is not met, the USB core will not be powered and hence will not function.

If VBUS is less than 4.1 V, FX3 behaves as if there is no VBUS present. 

How are you powering the FX3 device, is it bus powered or self powered?

Best Regards,

Yatheesh

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YatheeshD_36
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750 replies posted 500 replies posted 250 solutions authored

Hello,

If you are using an  19.2 MHz external oscillator and not a crystal to generate clock to the FX3 device through CLKIN, then the FSLC[2:0] should be 1 0 0, and the pins XTALIN, XTALOUT can be left unconnected. Please confirm the same.

Is the FX3 device on your board self powered? If this is the case, please reset the device manually by pulling it low after connecting the device to the host.

Best Regards,

Yatheesh

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I am actually using a crystal, the Epson FA-20H19.2000MF12Y, so the FSLC pins are configured correctly, all low.  I had the pins incorrect in the layout so I have the crystal prototyped sitting up about 1/2 inch off the board.  Do you think the added lead length could add enough capacitance to cause it to not start?  I am using 15pf caps for C1 and C2.  CLKIN and CLKOUT are both 1.4v p-p.   Tried toggling the reset pin with no luck.

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Hello,

Please refer to the crystal section in the FX3 hardware design guidelines.​ Make sure that the crystal used meets all the requirements and the actual power dissipated by the crystal is less than the drive level of the crystal.

Also, can you please share the schematics.

Best Regards,

Yatheesh

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I think I found my problem.  USB3_VBUS is  connected to 3.3v.  The datasheet says 4.0v minimum.  I can't prototype it to confirm since the pin is under the BGA.  Any ideas for me?  Can you confirm this could be a reason it's not coming up?

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Hello,

VBUS should have typical voltage level of 5V. If this condition is not met, the USB core will not be powered and hence will not function.

If VBUS is less than 4.1 V, FX3 behaves as if there is no VBUS present. 

How are you powering the FX3 device, is it bus powered or self powered?

Best Regards,

Yatheesh

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