Hi arm experts,
I wrote some simple C functions to check if the result of memcpy is expected after enable MMU and data cache on Cortex-A53. The assembly (got by disassembling with aarch64-none-elf-objdump) of the one of these functions…
Hi arm experts,
I wrote some simple C functions to check if the result of memcpy is expected after enable MMU and data cache on Cortex-A53. The assembly (got by disassembling with aarch64-none-elf-objdump) of the one of these functions…
Hi,
Before I write some Cortex A8 assembly code, I review some disassembly code of a small C program. In the following snippet, I don't understand the necessity of 'S' in ADDS. In fact, I don't see the usefulness of the whole line of
ADDS…
Dear Mrs. /Mr.
We are a company that manufactures traffic light systems. Our RnD department is in the designing process of a traffic light controller (TLC). The basic operational bloc diagram of the system is shown on the following figure:
As you can…
I have been given the task of selecting a suitable processor for a project in which we will have a dedicated processor.
The project will involve configuring HW and inverting matrices in C. We will use the Cholesky algorithm in double precision. We don…
Hello all!
So I'm working on a development with a Cortex M4 and there is something i don't understand, I was hoping someone could help clarify this:
This is the code I' using
(Assume R3 content is 1, R6 R8 the address needed to set PIN1, and…
Hello to all,
I would like to measure the current variation due to Functional Unit activation and deactivation. Can anyone help me out with the assembly program or the code through which I can measure this? I am using LPCXpresso 54114 board(ARM Cortex…
Hello,
I need help with heap initialization using scatter file and C++ startup.
MCU is STM32F407VGT6 (Cortex-M4).
Compiler is ARM Compiler 6.7, C++14.
The problem is that all variables which I create dinamically on the heap have wrong addresses. My HEAP…
This may sound stupid but I'd like to confirm my understanding of the processor behavior, in the event of a Data Abort. Section 3.8 of the Cortex R5 Techincal Reference Manual explains the Exception handling by the processor and my current understanding…
Hello!
I finally decided to share some info about a project I've been doing for the past 8 months. Currently it can be considered "alpha" or maybe "early beta" stage, but - despite literal meaning of these terms - the things that are already done (and…
Hi everyone,
I wonder if there is a documentation that explain how to program efficiently on arm cortex-m and arm cortex-r platform?
I found "arm system developer's guide", but i worried it was too "old-fashion" because it only contained upto armv6..…
Hi all,
I am trying to access the system control register in my ARM C program. The code (with heading 64 bit) I used is presented below. However I got the following error message during compilation.
/tmp/cc7Dc236.s: Assembler messages:
/tmp/cc7Dc236.s:31…
Hi,
I am developing a fixed-point MP3 & ACELP decoder on an Arduino Due. I realize that bit-banding makes a RMW sequence atomic but I notice fields in the Due hardware are multi-bit fields. Is there an atomic way to alter multiple bits? I realize that…
Using Cortex-R5F, I would like to get the contents of the 4-entry call-return stack (i.e. get the addresses). Is this possible through some indirect manner?
The goal here is to have the knowlege of the call tree above the current execution point (backtrace…
I have a very simple CortexM3 based virtual platform example as below

The amba_pv_m2 is connected to a memory in the top. The BusDecoder master port address range is 0x0-0x3FFFFFFF
I have the following C program
#include <stdio.h>
int main(int…
Background
I'm working part-time on a Cortex M0+ based SoC converting a very processor-intensive section of C++ code (inner-loop executed 10s of 1000s of times a second & compiles to over 400 instructions using GNU O3) and after almost 3 months of work…
Hello,
We bought ARM CM0+ deliverables from ARM. I want to design an SoC which has to get data from an another system .The aim of the SoC is to process an array of 4096 samples received from the external world.For the data interfacing, we are using GPIO…
Does anyone know where I can find the toolchain for developing apps on an A57 (Raspberry Pi 3) in Assembly Language? I am looking in particular for a Windows toolchain that will allow me to cross compile, but I'll take anything at this moment since all…