• STM32F030 CORTEX M0

    I have initialized the above controller in C++ in Keil 5uV. After the initialization, I want to jump to or enter a timing critical assembly language algorithm under the int main(void) statement. What is the preferred method to accomplish this?

    MJ

  • Does anyone use assembler only with an ARM MCU?

    I have only used assembler when working with MCU's. I can follow a C program but have not used it in any commercial product. Can anyone suggest a development platform to start off learning the ARM and C? I would probably work on a Cortex M4F as a start…

  • How to get absolute value of a 32-bit signed integer as fast as possible?

    Hi.

    I wonder how to calculate absolute value of a 32-bit signed integer in C as fast as possible. I saw that there is a FPU instruction VABS.F32, which do that in one cycle (above the floats). I thought, if it is possible to use it also with integers …

  • Assembly programming - yes, no, when, how to start, ... ??

    Hello again.

    As I am very interested in learning ARM architecture, I would have few questions regarding assembly programming. Questions refer primarily to programming Cortex-M processors, because they are the only one which I am using (at least for now…

  • Bit-banding in SRAM region (Cortex-M4)

    Hi.

    I would like to use bit-banding feature in SRAM, but don't know exactly how to implement it with C. I already use bit-banding in peripheral region with this kind of macro:

    #define BITBAND_PERI_REF        0x40000000…

  • Read/Write from register

    hi

    I'm using the soft-core Cortex-M0,keil uvision 5,vivado 14.4

    I am trying to implement a filter on my Cortex m-0 based FPGA

    the main idea of this project is to create an accelerator from my C code to reduce the execution time ..and since my accelerator…

  • cmsis NVIC question.

    Hello, Everybody. I have several questions.

    1. Please See the NVIC_Type structure. I don't understand about why ISER,ICER,ISPR and ICPR use size of array 1( I think It can use just __IO uint32_t ISER; ), and what does RESERVEDs do???

    2. I would like…

  • Cortex M4 exception return sequence

    Hi,

    I think I am just getting confused with this even if (or because of) I read the book and manuals again and again.

    At exception entry, the processor saves R0-R3, R12, LR, PC and PSR on the stack. Saving PC means that the address of the instruction to…

  • NXP LPC2378 (ARM7 core) communication via SPI protocol

    I want to communicate NXP LPC2378 (ARM7 core) to some other devices via SPI (Serial Peripheral Interface) protocol.

    So how to write a C code to communicate a particular device as a Slave with Master (ARM7 controller)?

  • Cortex-M0: What's included in the binary?

    Hi,

    I have two M0 projects.  The first project has only one assembly file startup.s.  The second project has one assembly file and one C file.  When I checked the memory map file of the second project (shown below), there are some extra object codes included…

  • [CM3]assembly language trouble

    CORE: STM32F103ZET6

    Hi,Pros.

         Here Monkey comes agian

    I have met a problem with my code,see below:

    /* --------- code here --------- */
     .section .data
_sp_usart:
     .word     _stack_usart
_stack_usart:
     .space     0x100…

  • Get current active interrupt priority

    Hi everybody,

    We are working on a simple priority RTC (run to completion) framework for the Cortex M3/M4. Thanks to the NVIC/BASEPRI, we got most of this functionality for free but we want to extend it to user tasks.

    In our implementation we need to determine…

  • Suitable ARM processor for Traffic Lights Controller

    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…

  • Help Choosing a processor

    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…

  • Cortex M4 Conditional Branch - Pipeline

    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…

  • Current Variation due to Functional Unit activation or deactivation

    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…

  • Cannot init heap using scatter file and C++ startup (Cortex-M4)

    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…

  • [C++11][Cortex-M] - distortos - object-oriented C++ RTOS for microcontrollers

    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…

  • efficient c programming

    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..…

  • Bit-Banding. Only 1 bit at a time?

    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…

  • CortexM3 : Issue when image start address is other than 0x0

    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…

  • M0+ Stack Pointer (PSP/MSP) Clarification

    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…

  • How to use GPIO interface IPs of ARM Cortex M0+

    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…