BeagleBone BBONEBLK_SRM, Справочное руководство

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REF: BBONEBLK_SRM
BeagleBone Black System
Reference Manual
Rev A5.2
Page 83 of 108
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When used for other functions, the HDMI frame cannot be used.

There is no way to power off the framer as this would result in the framer being
powered through these pins which would not a be a good idea.
In order to use these pins, the SW will need to reconfigure them to whatever function you
need the pins to do. To keep power low, the HDMI framer should be put in a low power
mode via the SW using the I2C interface.
8.1.2 eMMC Pins
The BeagleBone Black uses 10 pins to connect to the processor that also connect to the
P8 expansion connector. These signals are listed below in
Table 13 .
Table 13. P8 eMMC Conflict Pins
PIN PROC NAME MODE2
11 R12 GPIO1_13 mmc1_dat5
12 T12 GPIO1_12 Mmc1_dat4
13 T10 EHRPWM2B mmc1_dat1
14 T11 GPIO0_26 mmc1_dat2
15 U13 GPIO1_15 mmc1_dat7
16 V13 GPIO1_14 mmc1_dat6
17 U12 GPIO0_27 mmc1_dat3
19 U10 EHRPWM2A mmc1_dat0
20 V9 GPIO1_31 mmc1_cmd
21 U9 GPIO1_30 mmc1_clk
If using these pins, several things need to be kept in mind when doing so:

On the eMMC device, these signals are inputs and outputs.

The eMMC device will add a load onto these pins.

When used for other functions, the eMMC cannot be used. This means you must
boot from the uSD slot.

If using these pins, you need to put the eMMC into reset.
On power up, the eMMC is NOT reset. If you hold the Boot button down, this will force
a boot from the uSD. This is not convenient when a cape is plugged into the board. There
are two solutions to this issue:
1. Wipe the eMMC clean. This will cause the board to default to uSD boot. If you
want to use the eMMC later, it can be reprogrammed.
2. You can also tie LCD_DATA2 low on the cape during boot. This will be the same
as if you were holding the boot button. However, in order to prevent unforeseen