Dave Embedded Systems Axel ULite, Руководство по оборудованию

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AXEL ULite Hardware Manual v.1.0.2
reset signal is released.
7.3 System boot
NXP i.MX6UL processor implements a very flexible boot process. This
versatility comes at the price of a non trivial bootstrap configuration
scheme. Typical system-on-module (SOM for short) adopter does not
need to deal with such a complexity. In other words, he/she expects to
manage few boot configuration issues because it is assumed that most of
them are "hidden" within the SOM itself. Nevertheless, there are specific
applications where the system integrator needs full control of all the
bootstrap configuration options, even if the design is built upon a SOM.
These two needs - ease of use and configurability - clearly push in
opposite directions. During the inception of the
AXEL ULite product,
specific attention has been addressed to find a viable trade off to satisfy
such requirements. This effort has led to the options that are detailed in
the section Options for users. Reader can skip directly to this paragraph,
however he/she is encouraged to read
this section as well, in order to get
an overview of the processor's boot process.
It is worth remembering that an exhaustive discussion of this issue is
beyond the scope of this article. For more details, please refer to
4
7.3.1 Boot options
Please, keep BOOT_MODE1 = '0' for standard boot mode usage. For
further information on boot options, please contact the Technical Support
Team.
7.3.1.1 SPI NOR / SD option
BOOT_MODE0 0 1 or floating
Primary boot
device NOR SD
Fallback - USB serial downloader
Tab. 20 : SPI NOR / SD option
4 NXP, IMX6ULRM, i.MX 6UltraLite Applications Processor Reference Manual
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