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  • Synchronization primitives, do I need CLREX?

    Hi all,

    I'm trying to understand the LDREX/STREX commands in an ARM Cortex M3 MCU to implement atomic access to various variables (the goal is to implement semaphores/mutexes or increment/decrement shared variables).

    There are several ressources available…

  • about tail chaning of Cortex-M0

    Hello.

    I'm studying about the tail chaining of Cortex-M0.

    Is it same as Cortex-M3 or M4?

    Best regards.

  • 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…

  • coming from AVR 8-bitter,starting ARM CORTEX-M programming

    Hi everyone, as I wrote in the title, I'm coming from AVR 8-bit MCUs programming and in the last year I learnt a lot about AVR 8-bit architecture,CPU,registers and so on.

    I've done a few projects coding primarily in C and something in Assembly (serial…

  • I have an Arm 32-bit Cortex V3.10, Does anyone know the manufacturer/email?

    I need a configuration to get rid of the spacing between the numbers in a single barcode.

  • Is ARMv7-M3 thumb instructions compatible to ARMv7-A thumb?

    Hello guys,

    I am trying to verify some features of ARMv7-M3 in a software simulator platform for ARM. But this simulator only support ARMv7-A ISA.

    Is ARMv7-M3 instructions compatible to ARMv7-A, especially thumb instructions?

    Thank you very much.

  • Race condition between wake up event and WFI on Cortex-M3/M4

    When I read below thread in arm forum, I still not clear which one is the safety way.

    Cortex-M4: guaranteed wakeup from WFI?

    There're two solutions mentioned above, using WFE instead of WFI, and swap __WFI() and __enable_irq().

    I can understand WFE…

  • Can we Modify the Flash Memory Access Permission with MPU( Memory Protection Unit)

    Hi Sir,

             Can i change Flash Memory Permission through MPU??

    Thanks and Regards,
    Harshan.

  • in arm7tdmi, when FIQ and RIQ occures at same time so how both are executed sequentially,first FIQ and thenIRQ?

    in arm7tdmi, suppose instruction is being executed and at same time FIQ and IRQ both occur  at same time.now according to priority FIQ will be handled then IRQ  but my question is that how it will handled IRQ after  return from FIQ

    i means…

  • maximum level of functions than can be called within

    function1 calling function2, function2 calling function3, function3 calling function4 and so on.

    Maximum stage depends upon Stack Size, right? How to identify Stack Size and if required how to change it? I am using IAR and Fujitsu ARM Cortex M3 MB9AF312K…

  • I am very new to ARM, still understanding the terminologies. What is the difference b/w the Cortex family and the x-gene?

    Where can i get a list of all these family of ARM processors and their differences

  • Real Value of PC Register.

    I've been reading books on the ARM Cortex-M architecture and as already mentioned in other post, all the books are consistent in saying that the PC points four bytes (Thumb Instruction Set) forward due to Pipeline (prefetch).

    Did some testing with…

  • How long bitfields on which ARM?

    I need to be able to handle long bitfields as effectively as possible. Right now I need up to 64 bits in length.

    Are there instructions to set, clear and test individual bits in one cycle available for some of the architectures? Which? Particularly, will…

  • Cortex-A8 performance

    I'm working an a project on a Texas Instruments AM3517 Cortex-A8 processor. I was seeing less than expected performance, and did a simple comparison with a Cortex-M3 processor. The M3 performance was more than twice as good as the A8(?!).

    The test…

  • Help me jump into ARM world !(I know nothing but AVR)

    Hi,  Sorry if this is a long thread but i'm really confused.

    I program for AVR MCUs and also know about Arduino, I can program for different ATMEL MCUs with looking at datasheets, And i also programmed a few basic stuff on Cortex-M3 LPC1768, without…

  • If CAN receive buffer is'nt cleared before a new message arrives,will it over-write the earlier data?

    I am writing an application where a number of devices send messages to a common CAN processor in LPC1778 via CAN bus.

    FYI-i dont need to use Acceptance Filter because all messages have to be allowed.

    My question is that,if Device A sends a message and after…

  • ARM Cortex M3 STM32F207 processor hangs during the initializing if the code-size is more then 64k

    Hallo,

    I'm using a ARM Cortex M3 STM32F207 processor and if the code of  my project becomes a value of more than 64k, the processor hangs before the PC reach the __main().

    The code starts at 0x08020000 (sector 5) and hangs at a Breakpoint or any…

  • [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…

  • Break Points and Watch Points

    Greetings,

                   Sir,i am working on SWD, after  Research on Break Point & Watch Point i found One Thing That There are Some Comparators will Do These Things but I am not Very Sure That How These are Work …

  • 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…

  • How to learn ARM

    Hi everyone!!

    I am looking to work on some projects using ARM. I have completed a basic course on ARM M3/M4 (UT Austin 6.01x by Jon Valvano and Ramesh Yerraballi) online. Now, I want to learn advanced things, especially real-time applications. How should…

  • Continue the Target using Serial Wire Debug Protocol

    Greetings,
                   sir, i am working on serial wire debug protocol and till now i succeeded in halt,write,erase,and reset the target. now i am trying to implement breakpoints and watch points on my custom debugger. for break point i read "the definitive…

  • How many times same interrupt can be in pending state at a time? (In ARM CM-3)

    Could not find the answer to How many times same interrupt can be in pending state at a time? (In ARM CM-3) e.g. :

    We are processing one interrupt INT_RX, at the same time 3 more packets received. so I expect 3 times more this interrupt to appear sequentially…

  • [CM3]which clock sources can be closed?

    Hi bro,I am wondering which clock sources can be closed by software within stm32?thanks for helps.

  • How to get Cortex m3 soft core

    Hi,

    I needed to know where i could get arm cortex m3 soft core. Its for my masters thesis for which i'll be also using Keil uvision 5.

    Thanks in advance