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Author Topic: RasPi GPIO and init  (Read 2448 times)

Offline CentralWare

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RasPi GPIO and init
« on: March 30, 2015, 01:14:23 PM »
Board: Pi2B

A few quick questions (Béla?) regarding the Pi:

1) According to the overlay (tree) README document, please see the notes on act_led_gpio as the default pins.  On non-plus boards the default is listed as 16, on B+ and above, 47??  Based on the 10-key, was this a typo intending to be GPIO 17?  (Pin 13)

2) The file 6.1alpha4_v7.gz is assumed to be the init image.  Is it safe to assume it's a compressed CPIO file as is with x86/64?

3) If I leave SPI and I2S disabled and enable I2C, can the SPI pins be used as standard GPIO bits?  (I assume so, but have read conflicting stories online.)  I'll have limited I/O until my I2C boards arrive in the mail, so I'm looking to drive a couple separate 20x4 LCDs (4-bit mode) and a 16 channel relay board (16 bits) so I'm a few I/O short otherwise :)

4) Finally, I have not ripped into the boot image yet, but is it set up in the same fashion that the x86 version(s) are?  (ie: /etc/init.d/tc-config being the initial boot/configuration file, etc.)  I have a few things which will need to launch at the very beginning of the boot process, so if set up in a similar fashion this should be almost effortless!

Thanks in advance and take care!

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Offline bmarkus

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Re: RasPi GPIO and init
« Reply #1 on: March 30, 2015, 11:26:04 PM »
1) Open a GitHub ticket

2) yes

3) Don't know, try

4) Picore base is built on the same set of scripts as x86/x86_64 versions and boots the same way.
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