i.MX25 SODIMM PC Boot device options

Voipac i.MX25 SODIMM PC - Development kit is delivered with E-Fuses left intact by default, not programmed. Booting can be selected from various devices thus allowing all the possible options to be tested.

Modules support multiple booting options:

• NAND Flash
• microSD/MMC
• SPI Flash
• I2C EEPROM

All the configuration signals are tied down to supply voltage using external pull-up resistors. These resistors (R900 - R609) ensure that the default state is correctly initialized. More details can be found in datasheet shipped with the development kit:
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Boot configuration resistors can be located in the board assembly drawing.

The procedure described below requires extra care as the faulty E-Fuses will cause permanent module malfunction.

BE AWARE THAT E-FUSES PROGRAMMING IS NON REVERSAL PROCESS! WARRANTY CLAIM CAUSED BY IMPROPER E-FUSES PROGRAMMING WILL NOT BE ACCEPTED!

Programming E-Fuses

Dumping factory E-Fuses configuration before programming:

barebox:/ md -b -s /dev/imx_iim_bank0
00000000: 10 10 00 00 01 00 00 02 2b 2b 80 00 02 d9 f4 b1 ........++......
00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

Writing E-Fuses (example set also MAC address 00:01:02:03:04:05):

barebox:/ imx_iim_bank0.permanent_write_enable=1
barebox:/ mw -b -d /dev/imx_iim_bank0 0x1a+6 0 1 2 3 4 5
barebox:/ md -b -s /dev/imx_iim_bank0
00000000: 10 10 00 00 01 00 00 02 2b 2b 80 00 02 d9 f4 b1 ........++......
00000010: 00 00 00 00 00 00 00 00 00 00 00 01 02 03 04 05 ................

More information about E-Fuse banks layout can be found in the official NXP documentation.