arm

Assembly? LD & MOV

What's the difference between that instructions? By example in the ARM9 processor, it shouldn't be: ASM: mov r0, 0 C: r0 = 0; ASM: ld r0, 0 C: r0 = 0; ? I don't know why to use one or other :S ...

Output debug via printf on a Cortex-M3 CPU, stalls at BKPT instruction + confusion about JTAG and sw ports.

I have a Keil ULINK2 USB emulator box attached to the JTAG connector on my board, which is working fine with the Cortex-M3 CPU onboard (TI/Stellaris/LuminaryMicro LM3S series). It seems that both a JTAG and a SWJ-DP port share the same pins (and thus connector on your board) on these CPUs. One appears not to have ITM (printf) capabilit...

TCP/IP Protocol stack without an OS...

I'm looking for a TCP/IP stack that can be used without an OS. Our customer has an "aversion" to interrupts and doesn't want a real OS on a embedded board we're building. It's desirable to move as much of the functionality to FPGA as possible due to the fact we will be only using a 50 to 100 MHz Arm. And I'm pretty sure GPL licensed s...

How to use the multiply and accumulate intrinsics in ARM Cortex-a8?

Hi Guys, how to use the Multiply-Accumulate intrinsics provided by GCC? float32x4_t vmlaq_f32 (float32x4_t , float32x4_t , float32x4_t); Can anyone explain what three parameters I have to pass to this function. I mean the Source and destination registers and what the function returns? Help!!! ...

Why does this EXC_BAD_ACCESS happen with long long and not with int?

I've run into a EXC_BAD_ACCESS with a piece of code that deals with data serialization. The code only fails on device (iPhone) and not on simulator. It also fails only on certain data types. Here is a test code that reproduces the problem: template <typename T> void test_alignment() { // allocate memory and record the original addr...

How to measure program execution time in ARM Cortex-A8 processor?

Hi Guys, I'm using an ARM Cortex-A8 based processor called as i.MX515. There is linux Ubuntu 9.10 distribution. I'm running a very big application written in C and I'm making use of gettimeofday(); functions to measure the time my application takes. main() { gettimeofday(start); .... .... .... gettimeofday(end); } This method was ...

ARM SUB Instruction Operands

I'm working with the llvm-clang compiler, compiling simple C functions down to assembly on an ARMv7-A processor. I am trying to figure out what this instruction does. SUB sp, sp, #65, 30 Obviously it's making room on the stack pointer for some local variables, but I've never seen an ARM SUB instruction with four operands. I'm guessin...

codeSourcery G++ Lite Edition is a freeware?

hi, codeSourcery G++ Lite Edition is a freeware or Sharware? any help please? please see the link "http://www.codesourcery.com/sgpp/lite_edition.html" ...

ARM calling conventions on WinCE and Linux?

Do WinCE and Linux use the same calling convention on ARM? What are the differences? The documents I've found so far do not explain very well. For example on http://msdn.microsoft.com/en-us/library/ms864497.aspx, it says "Windows CE .NET Compiler" on one line, but "the ARM compiler" on the next line, and "CLARM" at the bottom, and it's ...

Mono on embedded ARM experience?

I'm evaluating components for a new embedded platform. CPU is an ARM9 and OS is Linux. Because the platform will be in use at least for 10 years I think the language should be chosen carefully as well. I'm already running Mono on possible target platform. Beside that I'm to dumb to compile Mono with my Compiler (according to Google more ...

specifed architecture type (arm) for file does not match it's cputype (7) and cpusubtype (3)

Hi there, I tried to use openLdap for my iphone app I'm developing at the moment. To compile openLdap I'm using the fat_build.sh from link text. I'm also developing with the Simulator 3.1.3 and under OS X 10.6.0. But at the last step $DEVROOT/usr/bin/lipo -arch arm lnsout/$LIBLDAP_NAME_static.arm -arch i386 lnsout/$LIBLDAP_NAME_sta...

how do you get gcc (or llvm) to generate ARM code from the OSX command-line?

On OSX 10.6.4 with iPhone SDK and Xcode 3.2.1 installed: $ gcc foo.c -arch arm gcc-4.2: error trying to exec '/usr/bin/arm-apple-darwin10-gcc-4.2.1':execvp: No such file or directory ...

Compiler errors while building a project which uses Eigen, the C++ template library for linear algebra...

Hi Guys, in my project I'm making use of Eigen C++ library for linear algebra and ONLY when I turn on the vectorization flags (mfpu=neon -mfloat-abi=softfp) for ARM NEON, I get compiler errors. I'm not able to understand whats going wrong. Do I need to enable any preprocessor directives for ARM NEON in the Eigen Library? main.c #inc...

CodeSourcery giving compilation error: missing bits/c++config.h

Hi Guys, in my project I'm making use of Eigen C++ library for linear algebra. ONLY when I turn on the vectorization flags (-mfpu=neon -mfloat-abi=softfp) for ARM NEON, I get a compiler error - c++config.h no such file or directory. I'm not able to understand whats going wrong, what is this bits/c++config.h? What should I do to fix thi...

ARM-linux4.3.2, can't open socket with PF_PACKET type

Hello, I'm using FriendlyARM with linux 2.6.29 and compiling with ARM-Linux GCC 4.3.2 When trying to open a socket with PF_PACKET it fails with errno 97, Address family not supported by protocol. This is an example program that illustrates the problem - #include <stdio.h> #include <sys/socket.h> #include <netpacket/packet.h> #in...

How to make sure a buffer is stored in cache on arm 9

I have a character buffer which i want to place in Cache ,how to make sure that in memory map the compiler places this in DCache. Compiler is RVCT 3.1 ...

Current ratings for SAM7-P256 Olimex board

Hi, I have bought an Olimex SAM7-P256 board. The power supply is given as 6V AC or DC. There is not max current ratings. I am seeing different current ratings for 6V power supply in market. Can anyone give me the current ratings for the board. Thanks. ...

How to start with olimex sam7-p256

Hi, I have bought a olimex sam7-p256 development board. Can anyone guide me to a website or tutorial that gives an idea as to how to install the tools and start using it? I am using ubuntu 9.10. Though I have got a windows OS, I would prefer to use it under linux. Any help on the good starting point in windows / linux will be good. Than...

DebugBreak for iPad

Hello, I want to make DebugBreak for iPad and found that asm{trap} should work, but there is a problem: if I use asm{trap} I have error: asm blocks not enabled, use `-fasm-blocks'. If I enable -fasm-blocks I have another error: -fasm-blocks option not supported for ARM. Do you know another way to implement DebugBreak or to make asm co...

Instruction timing on ARM Cortex-m3 (Specifically LPC1343)

I'm looking to write some very timing sensitive code on an LPC1343 where I need to count exact clock cycles. There are two issues :- I've read that code executing from the internal flash memory isn't always able to run at the full 72Mhz and wait states might be introduced. But I can't find any "official" document about this. I saw one ...