Internal Boot - Digi ConnectCore 6UL Hardware Reference Manual

About the ConnectCore® 6UL
BOOT_CFG1 selects the boot device through BOOT_CFG1[7:4] bits:
BOOT_CFG1[7:4] Boot device
0000
0001
0011
010x
011x
1xxx
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]
BOOT_CFG2[2]
BOOT_CFG2[3]
BOOT_CFG2[4]
BOOT_CFG2[5]
BOOT_CFG2[6]
BOOT_CFG2[7]
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:
Bootstrap configuration Corresponding GPIO Configuration
BOOT_CFG1[0]
BOOT_CFG1[1]
ConnectCore® 6UL Hardware Reference Manual
NOR/OneNAND (EIM)
QSPI
Serial ROM (SPI)
SD/eSD/SDXC
MMC/eMMC
Raw NAND
LCD_DATA9
LCD_DATA10
LCD_DATA11
LCD_DATA12
LCD_DATA13
LCD_DATA14
LCD_DATA15
LCD_DATA0
LCD_DATA1
100K pull-down
100K pull-down
100K pull-up
100K pull-down
100K pull-up
100K pull-down
100K pull-down
0
0
Bootstrap
18