embedded

GCC C++ (ARM) and const pointer to struct field

Let's say there is a simple test code typedef struct { int first; int second; int third; } type_t; #define ADDRESS 0x12345678 #define REGISTER ((type_t*)ADDRESS) const int data = (int)(&REGISTER->second)*2; int main(void) { volatile int data_copy; data_copy = data; while(1) {}; } Which is compiled in Code...

Pleo LifeOS toolsuite

Does anybody know of any tool suites that are still available for Pleo LifeOS (1.0 or 1.1)? Supposedly, there was a tool chain for Pawn at some time, but that seems not to be available anymore. Or is it? Any other (true) programming APIs? ...

ARM linux and cross toolchain issue

Hi, I have a problem probably with my arm toolchain but maybe there's something other that I do wrong. I have Chinese made dev board qq2440 using Samsung s3c2440 ARM9 uC. I'm using Ubuntu x86 with native gcc(4.3.3) and cross-compile version arm-unknown-linux-uclibc-gcc (crosstool-NG-1.3.2) 4.3.2 I followed tutorials from http://blog.le...

Which Linux RTOS solution should I choose?

I'm preparing myself to build RTOS solution on top of Linux this going to work on embedded device. I've done some investigation by myself but still I'm a bit confused. Those are my criteria: Easy to run on Samsung s3c2440 ARM9 machine Open Source Works together with Linux Good community support I've seen RTLinux and Xenomai. Xenomai...

What does it mean to attach ROMFS in RAM?

I'm building a kernel for an ARM platform running uClinux 2.4 and under "General Setup" in the Linux configuration there is an option called "m68knommu-style attached romfs in RAM support". My ARM assembly skills are somewhat limited but as far as I can tell if I enable this option the ROMFS is copied to the end of the kernels BSS. What...

Run time Data and Code memory size estimate

Hello All, I am working on a project, C programing language, to develop an application, that can be ported on to a number of different microcontroller platforms, such as ARM\Freescale\PIC microcontroller. I am developing this application on Linux now and then I will have to port it to the above said platforms. I would like to know, are...

Intel C++ Compiler for Windows CE ...

Two years ago I used eMbedded Visual Studio for Windows CE based application development. I had about 40% app performance acceleration with Intel C++ Compiler(v1.2 or v2.0) in comparison with default MS compiler (floating point issues, ARM). It was looked really helpful for me. I do remember that downloaded it from official Intel site....

Is switch from MFC to QT or WTL (or other GUI toolkit) recommended for Windows CE development?

There are pretty many questions regarding C++ GUI toolkits for Windows, but they mostly apply to desktop OS versions. I'm now starting a C++ project for Windows CE 5.0 VGA hand-held device, and thinking about what GUI library to choose. I have some experience using MFC in Windows CE projects, but there are some known weak points of MFC ...

Trying to flush the PowerPC 750 data cache

I'm writing a routine to flush the PowerPC750 data cache before turning it off when using write back mode. I've found the IBM application note on programming the caches which includes a flush routine, but I am confused by the example code. I think it might be a mistake in the example but thought I'd check. In Listing 2 there are two loo...

Mobile Devices get HTTP 504 Error

I am trying to debug why a mobile device trying to connect to my embedded web server is getting a "HTTP 504 Error: Gateway timeout". A PC can connect just fine, it's just the Blackberries and mobile phones that get this error. What does a 504 error mean? What can I do about it? ...

C pointers vs direct member access for structs

Say I have a struct like the following ... typedef struct { int WheelCount; double MaxSpeed; } Vehicle; ... and I have a global variable of this type (I'm well aware of the pitfalls of globals, this is for an embedded system, which I didn't design, and for which they're an unfortunate but necessary evil.) Is it faster to access t...

C memory space and #defines

I am working on an embedded system, so memory is precious for me. One issue that has been recurring is that I've been running out of memory space when attempting to compile a program for it. This is usually fixed by limiting the number of typedefs, etc that can take up a lot of space. There is a macro generator that I use to create a ...

Data transmission through USB

I want to develop code to transmit data from system to PIC through USB. Can anybody give good link regarding data transmission through USB. because i am new to this. NOTE: Very simple is code is enough to me. Thanks in Advance ...

What would be a good (de)compression routine for this scenario

I need a FAST decompression routine optimized for restricted resource environment like embedded systems on binary (hex data) that has following characteristics: Data is 8bit (byte) oriented (data bus is 8 bits wide). Byte values do NOT range uniformly from 0 - 0xFF, but have a poisson distribution (bell curve) in each DataSet. Dataset ...

ARM9 SVC_STACK out of range?

I'm debugging some odd ARM exceptions in an embedded system using the IAR workbench toolchain. Sometimes, when an exception is trapped the SVC_STACK is reported as out of range (very out of range!) Is this relevant, or just an artifact of the J-Link JTAG debugger? What is the SVC_STACK used for? It is set to 0x1000 size, but when it is o...

What microcontroller (and other components) would I need to create a timer device?

As a hobby project to keep myself out of trouble, I'd like to build a little programmer timer device. It will basically accept a program which is a list of times and then count down from each time. I'd like to use a C or Java micro controller. I have used BASIC in the past to make a little autonomous robot, so this time around I'd like ...

How best to handle large buffers in a layered protocol stack?

Hi, I am working on a simple protocol stack for a small embedded system (multidrop, rs485 type stuff). In this stack, losely models after OSI layers: Application Network Datalink physical (serial driver) Each layer has its own header / footer portion that wraps the payload of the layer above it. I will be using my own buffer pool ...

Could ARM9 Prefetch Abort Exception be a software problem?

So I'm getting a "prefetch abort" exception on our arm9 system. This system does not have an MMU, so is there anyway this could be a software problem? All the registers seem correct to me, and the code looks right (not corrupted) from the JTAG point of view. Right now I'm thinking this is some kind of hardware issue (although I hate to ...

ARM Data Abort error exception debugging

So now I understand that I'm getting a ARM Data Abort exception - I see how to trap the exception itself (a bad address in the STL library), but I would like to walk back up the stack frame before the exception. I'm using the IAR toolchain, and it tells me the call stack is unavailable after the exception - is there a trick way to convin...

video format with minimal decode time.

Hi Friends, I am working on embedded device with 266 Mhz processor and 32 Bit bus and 480x272 screen. we want to play fullscreen video with 1024 kbps Bitrate and 24 fps. Is there any video file format which is bigger in size but fast to decode than H263 and H264. Thanks, Sunny. ADDED I am using processor version ARM926EJS, Arch is...