Custom i.MX283 board, odd behaviour when booting SD card under battery power

[jannyman]

Dear all,

I am bringing up a custom board with a i.MX283 part. I am working with the fsl-community-bsp Yocto with Kernel 2.6.35.3-r45.

My board is intended to boot from a (micro) SD card.  It seems that booting fails with most (but not all) SD cards, if the board is under battery power only. If I connect a wall USB charger to the USB port, the board can boot from all SD cards. Here is the output from Debug UART:

(When Battery connected the following immediately appears:)

HTLFLCMHTLLCL0x8050100b

HTLLCL0x8050100b

(Then a 20 seconds interval)

0x80502008

          HTLFLCMHTLLCL0x8050100b

(Again, 20 second interval)

0x80502008

          HTLFLCMHTLLCL0x8050100b

We now connect the board to a USB charger, then after some delay to board boots:

0x80502008

          HTLFLCMHTLLCLLC

U-Boot 2014.10+fslc+g5fd0b60 (Sep 29 2015 - 13:57:17)

(etc...)

The board appears to boot reliably every time when powered with a USB charger. Also, if there is no battery connected, the board boots immediately after applying power, with all the SD cards I have tested. I happen to have one SD card from which the board boots immediately after applying power, but this seems to be a coincidence. If I transfer the same contents on a different SD card, it wont boot until charger is connected.

I have an I2C EEPROM chip on the board, and I have loaded it with the patch "mx28_polarity_issue_ssp1.sb" and I have set up my board to boot from EEPROM. I have blown the ENABLE_SSP_12MA_DRIVE fuse. However, I am still experiencing the above problems.

Do you have any tips how to solve this problem? I expect the board to boot immediately when battery is connected.

BR,

Jan

[jannyman]

Let me just clarify:

The PSWITCH on my board is has a pull-up to VDDXTAL, so it attempts to boot immediately when it has power.

When the board is under battery power, only one of the tested SD cards succeeds in booting; others fail with error "HTLFLCMHTLLCL0x8050100b".

When a USB charger is connected to the board, the board can boot all SD cards.

When no battery is connected, all SD cards can be booted when a USB charger is connected or the board is connected to a PC with USB cable.

What could be the problem?

[igorpadykov]

Hi Jan

0x8050100b indicates an error in the CRC checking, could it

be from battery insertion, contact ringing, does board boot with

just pressing pswitch (disconnected from VDDXTAL) ?

One can try boot FSL BSP

i.MX28 Linux 2.6.35 Source Code Files and documentation

i.MX28 Evaluation Kit|Freescale

Best regards

igor

[jannyman]

Hello Igor,

Thanks for your reply. I tested my image on the MX28EVK and a Li-ion battery connected to J86, I get the same error 0x8050100b after I press PSWITCH.

Then I tested one of the sample SD cards that came with the MX28EVK kit, it does actually boot without problems in the same conditions (under battery power)

So I guess I will try to build my image with FSL BSP as you suggested.

Thanks,

Jan