iMX233 USB connection mode

[paolomartinetti]

Hi everybody.

i have some problem with my device, 233-equipped, when i plug USB cable first on computer and after in device.

The device-plug probably connects D+/ D- pins before power and ground ones.

Could be this wrong? After this 'bad' connection, my device stops working and seems powered off.

Is there any way to avoid this acting on kernel code?

Thanks in advance

[igorpadykov]

Hi Paolo

it is not allowed to apply voltages to unpowered processor.

This can not be configured in software.

Best regards

igor

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[paolomartinetti]

My device is powered with a Li-Ion battery. I attach USB connecting data pins before Power and Ground pins.

[igorpadykov]

it does not matter, if processor is not turned on

(unpowered)

Power-up can be started with one of several events:

PSWITCH pin >= minimum MID level PSWITCH for 100 ms

VDD5V power pin > 4.25 V for 100 ms