In the figure below is shown the boot configurations available, from
memory devices
, settings the nSD_BOOT.signal.
Figure 22
The figure above shows the implementation of the boot options applied to a generic carrier board. The signal used to configure the boot
option on the ENGICAM EVABOARD is named EIM_DA7 (pin 80, nSD_BOOT signal on GEA M6UL) which is pulled up with a 12KOhm
resistor on the module.
In the standard condition, the signal in the evaluation board is setting to boot from the module's internal memory devices (NAND or
eMMC) jumper left open; the boot from the SD card is achieved simply closing the jumper.
Following, how to implement the signals logical level for a custom starting sequence.
The first sequence is already implemented in the module, nSD_BOOT signal left floating or pulled up.
BOOT from Internal Module's Memory Device
Pin Number
EVABOARD Signal
LOGIC LEVEL
80
nSD_BOOT
1
Table 22
Setting the nSD_BOOT signal to
high logical level
:
•
if module is equipped with NAND, the boot run from NAND
•
if module is equipped with eMMC, the boot run from eMMC
The NAND and eMMC
can NOT
coexist in the module
.
The choice of booting from SD1 means short-cutting the jumper A in the evaluation (or carrier) board. It's possible to have the same
effect by pulling down the signal nSD_BOOT.
BOOT FROM SD1 Device
Pin Number
EVABOARD Signal LOGIC LEVEL
80
nSD_BOOT
0
Table 23
Whatever starting sequence is choosing consider that the pin 80 of the main connector is used to the boot configuration.
WARNING
:
remember that the peripheral SD2 can not be used in the modules that mount the eMMC
Note: for using of any customized boot options please refer also to the NXP i.MX6UL reference manual
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