REL 1.2
Page 17 of 56
i.MX6 SODIMM SOM Hardware User Guide
iWave Systems Technologies Pvt. Ltd.
2.6.1
Boot Setting
i.MX6 CPU boot process begins at Power On Reset (POR) where the hardware reset logic forces the ARM core to
begin execution starting from the on-chip boot ROM. i.MX6 CPU 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
behaviour of the device. i.MX6 SODIMM SOM boot media is fixed as SPI flash by On-SOM GPIO setting in hardware.
Note: Contact iWave if different boot media support is required other than SPI flash.
i.MX6 SODIMM SOM supports two boot mode signals on SODIMM Edge Connector. BOOT_MODE is initialized by
sampling the BOOT_MODE0 and BOOT_MODE1 inputs on the rising edge of POR_B. These Boot mode selection
signals are connected to SODIMM Edge connector and desired boot mode must be set from the carrier board as
explained in the below table.
For more details, refer SODIMM Edge connector pins 182 & 184 on
Table 3: Boot Mode Pin Settings Truth Table
BOOT_MODE [1]
(SODIMM Edge Pin 184)
BOOT_MODE [0]
(SODIMM Edge Pin 182)
Boot Type
Description
1
0
Internal Boot Mode
In this mode, i.MX6 boots from the
boot media selected by Boot media
GPIO p
in’s settings
. By default, SPI is
selected as boot media in i.MX6
SODIMM SOM hardware.
0
0
Boot From eFuses
In this mode, i.MX6 boots from the
boot media selected by i.MX6 eFUSE
settings.
Note: i.MX6 eFuse setting is not
modified by iWave from silicon
shipped value.
0
1
Serial Downloader
Mode
In this mode, i.MX6 boot media can
be Programmed through its USB OTG
interface using manufacturing tool
supported by NXP/Freescale (MFG
Tool).
Important Note: To make i.MX6 SODIMM SOM boots as expected, make sure to set the desired boot mode from the
carrier board.