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| − | =Pin functions (mux)=
| + | #REDIRECT [[EXT_Connector]] |
| − | By default UART2 pins are set up as GPIOs, and UART3 as an UART.
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| − | ==Changing pin functions under 3.2 kernel==
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| − | Described in the [http://boards.openpandora.org/index.php?/topic/4497-talking-to-the-gpios-on-the-ext-connector/page__st__40#entry195457 following forum post]
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| − | =Power supply=
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| − | Currently always set to supply 2.8V, changing this requires patching bootloaders (xload and u-boot).
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| − | This is connected to VAUX3 supply on PMIC, with these programmable voltages (200mA max):
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| − | 1.5V, 1.8V, 2.5V, 2.8V and 3.0V, with 2.8V as default.
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| − | '''warning''': at the time of this writing, both bootloaders (xload and u-boot) set this to 2.8V unconditionally, so don't rely on this providing other voltages during reboot until you patch both bootloaders.
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| − | =GPIOs=
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| − | Can be controlled using GPIO sysfs class device, as described in beagleboard tutorials [http://bbfordummies.blogspot.com/2009/07/1.html here].
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| − | =UART3=
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| − | On older firmwares, kernel messages are directed there. SuperZaxxon or later have that disabled.
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| − | On all firmwares released so far terminal with a shell is attached to UART3. The port runs at 115200 8N1 baud rate.
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| − | ==Disabling kernel messages==
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| − | To disable kernel mesages, you need to edit kernel boot arguments. Probably easiest way to do it is to create autoboot.txt and place on root directory of a card in slot1 with this content:
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| − | <source lang="bash">
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| − | setenv bootargs ubi.mtd=4 ubi.mtd=3 root=ubi0:rootfs rootfstype=ubifs rw rootflags=bulk_read
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| − | </source>
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| − | Alternatives are using u-boot environment (configure through USB or UART3 serial before system boots up) or patching and reflashing u-boot itself.
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| − | ==Disabling attached terminal==
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| − | For this you need to edit /etc/inittab on pandora rootfs and comment out these lines:
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| − | <source lang="bash">
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| − | #S0:2345:once:/sbin/getty 115200 ttyS0
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| − | #O2:2345:once:/sbin/getty 115200 ttyO2
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| − | </source>
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