AnsweredAssumed Answered

Problem with i.MX28 ROM BOOT

Question asked by Jan Elfstrom on Nov 5, 2014
Latest reply on Nov 24, 2015 by Dennie de Groot


We just received a batch of first prototypes based on the i.MX28. The following happens at the debug-port:



(Repeats with some seconds interval)

It is not strange that the FLASH fails as it is empty and the USB0 is not connected at the time.

When we connect the USB0 to be able to flash our system Windows does not recognize it as an HID-device. (Happens in Linux too)

We did the same using the EVK and it works fine.

Noted was that the debug-info stopped when USB0 is connected.


We use external +5V (or USB if available) to power the PMU through the VDD5V but the voltage levels are a little strange:

VDDIO 3.155V

VDDA 1.797V

VDDD 1.175V

VDD4P2 0.838V



The first three are reasonable, but the VDD1P5 is not used and has only a 33uF capacitor connected. VDD4P2 seems odd too and is not used externally.

The PMU is configured according to the i.MX23 reference design with 5V only (no battery).

The DC/DC inductor is in place.

Current consumption is around 110mA@5V.


This has really put a stop for us and I would very much appreciate any help.