38 lines
1.6 KiB
Plaintext
38 lines
1.6 KiB
Plaintext
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Right, I know...Got my raspberry pi today.
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This repo serves as a collection of low level examples. No operating
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system, embedded or low level embedded or deeply embedded, whatever
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your term is for this.
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From what we know so far there is a gpu on chip that boots off of I
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assume an on chip rom. This goes to the sd card and does things. it
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appears that the entry point for us as programmers is the kernel.img
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file, which appears to be the memory image copied into the ARM memory
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before releasing reset on the ARM processor. The name of course because
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this is intended to be a Linux based educational computer, but it is
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just a file name, just a memory image.
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You will want to go here
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http://elinux.org/RPi_Hardware
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And get the datasheet for the part
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http://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf
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(might be an old link, find the one on the wiki page)
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And the schematic for the board
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http://www.raspberrypi.org/wp-content/uploads/2012/04/Raspberry-Pi-Schematics-R1.0.pdf
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(might be an old link, find the one on the wiki page)
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Ultimately I will make a uart based bootloader. For now start with
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blinker01
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I dont normally use .data nor gcc libraries nor C libraries so you can
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build most if not all of my examples using a gcc cross compilerl. Basically
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it doesnt matter if you use arm-none-linux-gnueabi or arm-none-eabi.
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what was formerly codesourcery.com still has a LITE version of their
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toolchain which is easy to come by, easy to install and well maybe not
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easy to use but you can use it. Building your own toolchain from gnu
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sources (binutils and gcc) is fairly straight forward and at some point
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will create a script to do that for you.
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