Serial Download fails on i.MX53 board

[alexanderbondar]

I have designed custom board based on i.MX53 QSB. Board successfully loading from SD but fails to download via USB in serial boot mode. PC does not see USB devise when I switch my board in serial boot mode but see it when Linux running so I suppose that USB OTG is ok. All UARTs RX pins described in RM 7.8.2.1 are disconnected. Is there any way to trace ROM downloader?

[johnphy]

             I have met the same question. When I set BOOT_MODE1 and BOOT_MODE2 high , it's in serial download mode, but my PC can not recognize the USB device .Through device manager I can see the VID and PID of the unkown USB device are 0x0000.

            But when the board runs in normal mode , the USB port can be recognized by  PC.

           Have you got the right solution? Thanks.

[Yuri]

1.

Please check Your design, using Chapter 1 (Design Checklist)

of the "i.MX53 System DevelopmentUser’s Guide".

2.

  When UART is configured (by the boot ROM in serial boot mode), but

corresponding pins are left free - it may cause boot ROM hanging in UART

polling because of possible noisy environment.   

[alexanderbondar]

I think here is something different from just noise on floating pins. When I power on board and reset processor PC does not see it. But if after power board up I load and run Linux and after that set jumper for serial download and reset processor then iMX53 is appeared on USB device list in PC.

[Yuri]

You can try JTAG debugging : I mean it is possible to connect a JTAG probe to the i.MX53, but - do not run a software

debugger in order to allow boot ROM to start. After the system hangs one can try to check what occurs in (debug) step

mode. If boot ROM hangs in UART testing it may be seen via code analyzing.