problem of DFU

[revol]

I made a board with LPC4320. I set the boot pins as USB0. But when I connect the board with PC, nothing happens. There is no USB device recognized, let alone entering DFU mode.

Did I miss something? Is there anything need to be set when booting the MCU for the first time? Install some drivers for example.  Or I should just check my soldering?

Could anyone help me?

Many thanks!

[Carlos_Mendoza]

Hi Lifan,

The USB0 boot mode requires that a 12 MHz external crystal is connected to the XTAL1/2 pins. The boot code configures the CGU accordingly. The USB clock is respectively set to 480 MHz or 60 MHz.

Hope it helps!

Best Regards,

Carlos Mendoza

Technical Support Engineer

[revol]

Hi Carlos,

Thanks for help.

So the external crystal should start to work when booting with the boot pins set as USB0, right?

I checked the crystal, it's not vibrating. I‘ll look into it.

Regards,

Lifan

[Carlos_Mendoza]

Hi Lifan,

Yes, please let us know if it works!

Best Regards,

Carlos Mendoza

Technical Support Engineer