Raspberry Pi Stack Exchange
Raspberry Pi Stack Exchange

Questions tagged [assembly]

A low-level programming language providing symbolic representation of machine code.

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Write an OS for Raspberry Pi in C

I already found the Baking Pi tutorials, but they only use assembly language. I followed the first lessons, but I am already wondering how to use C instead. I mean, there is a reason they invented higher-level languages. I tried just compiling the C…
11684
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How do I read the cpuid in aarch64 asm?

In armv7 / 32bit mode I can read the cpuid using uint32_t arm_cpuid; __asm__("mrc p15, 0, %0, c0, c0, 0" : "=r"(arm_cpuid)); This gives 0x410FD034 for RPi3 and 0x410FD083 for RPi4. What is the equivalent for that in aarch64 / armv8…
Goswin von Brederlow
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Does the Raspberry Pi 4's processor support ARM's SHA256 instructions?

According to Wikipedia, every Armv8 processor should support sha256 hashing instructions however /proc/cpuinfo doesn't list it. Could there be a failure to identify the feature by the kernel? processor : 3 BogoMIPS : 108.00 Features : fp…
erolll
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BCM2835 GPIO Pins vs. Physical Pin Numbers

Good morning. I am attempting some low-level assembly coding for Raspberry Pi. Using the BCM2835 Peripherals Doc, I have successfully been able to work with the GPIO controller on my RPi Model B rev. 2.0 to turn the "ACT" LED on (which I know is raw…
Jacob B.
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gcc does not compile code that compiles in 'as'

I'm trying to learn assembly using the raspberry pi. I have code that compiles using as but will not compile with gcc. I thought that as was the backend for gcc assembly so I'm confused why it is not working. It says that udiv is undefined. test.s …
user668074
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Why does adding a nop or constant break my code?

I am learning the ARM architecture via bare metal programming on the Raspberry Pi 3. I have a booting "kernel" that prints out some info. I have reached a point that I don't understand what is happening. I have two pieces of boot code below, one…
Jacob Calvert
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OS-less raspberry pi 2 debugging of Assembly language

I have a Raspberry Pi 2 without an OS installed. I have an assignment where I have to create and display some code in assembly language for the Pi 2. The lab that we have set up at school has hardware/software that allows us to run and test the code…
SeesSound
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Regarding assembly language programming in Raspberry Pi

I am learning assembly language programming in Raspberry Pi 2 model B. I know about Code::Blocks and gdb. Using assembly language the processor's register can be controlled, but I want to control the peripheral's registers (BCM2835 peripheral)…
vivek
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Disassemble i386 in Raspbian?

I want to disassemble i386 machine instructions into human readable text in Raspbian. I am a rookie Linux user and don't know the configuration of installed tools, but from what I understand I need an architecture for i386 for objdump. objdump -D…
Statement
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Baking Pi Lesson 02 does not work on B+

I would like to comprehend lesson 2 of Baking Pi, but I am not able to get the LED blinking. I am using Windows and have installed Cygwin and the ARM tool chain. As explained in the requirements, I have downloaded the latest Raspbian, which works…
ceving
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ASM - how do I write graphics straight to the screen

I have some old RISC OS assembly programmes I wrote a few years back and I want to port them to Raspberry Pi. I ran Mode 28 and wrote output directly to the screen using the memory address where v-ram started -- i.e., I didn't use an SWI call. Is…
JohnB
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Assembly code on Raspberry Pi

What's the file extension for assembly code? Can it even be written by a text editor? My plan was to use nano to write the program (for syntax highlighting), so would that work? If not, what do I need to use? Can you even compile ARM assembly code?
Beta Decay
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Run program on Baking Pi ARM ASM OS

I am following the Baking Pi Raspberry Pi ASM OS tutorial here, and I thought that it would be cool if I could create a compiler/runner for like, BASIC or a language I create. I don't have the skill yet to create something like that, so hopefully I…
RPiAwesomeness
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bootcode.bin RPi 3

I've been reading this document: https://www.raspberrypi.org/documentation/hardware/raspberrypi/bootmodes/bootflow.md About the boot process of the Raspberry Pi. I want to make a simple "Hello, World!" operating system in AArch64 assembly and was…
Cromulent
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On-board LED connection to GPIO

I stumbled on this tutorial: http://www.cl.cam.ac.uk/projects/raspberrypi/tutorials/os/ok01.html Unfortunately this is only made for the B rev2 board, whereas I got a B+ board and the board setup is slightly different. On the schematics of the rev2…
nemo
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