MYiR MYD-Y6ULX Linux, Руководство по эксплуатации продукта

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MYD-Y6ULX |
Product Manual
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the system is powered down, if the RTC does not need to work, it is not require to provide
this power rail.
4.2.2 Boot configure switch
The boot process begins at the Power-On Reset (POR) where the hardware reset logic
forces the ARM core to begin the execution starting from the on-chip boot ROM. The boot
ROM code uses the state of the internal register BOOT_MODE[1:0] as well as the state of
various eFUSEs and/or GPIO settings to determine the boot flow behavior of the device.
MYD-Y6ULX is equipped with a 4 bit switch to change the boot device.
Please refer to the schematic for the boot state as below,
Figure 4.2 Boot Configure Switch
There are some differences between the NAND Flash version and the eMMC version in
the boot Configure and the hardware. For NAND Flash version, remove R207 and R209,
mount R206 and R208. For eMMC version, remove R206 and R208, mount R207 and
R209.
Bit1 and Bit2 are used to select boot device. Please refer NAND Flash version setting as
below.
Switch BIT1 BIT2
SD Card ON OFF
NAND Flash OFF ON
Table 4.1 NAND Flash Version Boot Configure
Please refer eMMC version setting as below,