I've built my own prototype board with a factory imx233, which does not have the OTP bit HW_OCOTP_ROM0::SD_MBR_BOOT blown. It is a 128-QFP 5v only design, based on the reference schematics (rev C). To test this board, I have a small boot program that will flash an LED.
Currently my board does not show signs of life This could be because of several things:
1) I've made a hardware design error.
2) My BCB boot is incorrect.
All power rails seem to be within tolerance, and the crystal is oscillating at 24MHz.
I have an OLinuXino development board which does have the OTP bit HW_OCOTP_ROM0::SD_MBR_BOOT blown so that it boots from MBR.
Will the I.MX233 boot from BCB if the OTP bit is blown and there is no MBR on the SDCard? The OLinuXino has an LED on the same GPIO as my custom board, and it boots my test when there is an MBR present, but not BCB.
I've followed the BCB advice in this thread https://community.freescale.com/thread/311484
Is the size of the SDCard significant? I have tried creating the BCB in the last sector of a 2MB partition _and_ in the last sector of the physical card, which is 8GB. Which is correct?