User Manual

About the ConnectCore® 6UL Internal boot
ConnectCore® 6UL Hardware Reference Manual
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the system. These parameters are configured through fuses, which are burned in order to set their
values. This means that the configuration is irreversible.
BOOT_CFG1 selects the boot device through BOOT_CFG1[7:4] bits:
BOOT_CFG1[7:4] Boot device
0000 NOR/OneNAND (EIM)
0001 QSPI
0011 Serial ROM (SPI)
010x SD/eSD/SDXC
011x MMC/eMMC
1xxx Raw NAND
There are many other registers that configure the different boot devices. For a complete description
of the booting configuration, refer to the NXP i.MX 6UltraLite Applications Processor Reference
Manual (Chapter 8: System Boot).
Internal boot
Internal boot is the recommended boot mode for development purposes. When this boot mode is
selected, the selection and configuration of the booting process is done through the same registers
used when booting from fuses. However, this time the values of some registers are overridden using
multiple GPIOs, which are latched during power-up.
The following configuration is done internally in the ConnectCore 6UL module in order to enable
booting from the NAND memory:
Bootstrap configuration Corresponding GPIO Default configuration
BOOT_CFG2[1] LCD_DATA9 100K pull-down
BOOT_CFG2[2] LCD_DATA10 100K pull-down
BOOT_CFG2[3] LCD_DATA11 100K pull-up
BOOT_CFG2[4] LCD_DATA12 100K pull-down
BOOT_CFG2[5] LCD_DATA13 100K pull-up
BOOT_CFG2[6] LCD_DATA14 100K pull-down
BOOT_CFG2[7] LCD_DATA15 100K pull-down
You must also set up BOOT_CFG1[7:0] register when booting from the internal on-module NAND when
Internal boot mode is selected. It must be configured externally (outside the module) as shown in the
following table: