Hi, I'm trying to compile libpng & zlib using the RVCT 4.0 armcc compiler. However armcc cannot find 'fcntl.h', which I assume is a standard C library. Cygwin has fcntl.h (and the associated files types.h and _types.h), but when I use those, I get various compilation errors. Should I be using Cygwin's version of standard C libraries, o...
I am porting an application to an ARM platform in C, the application also runs on an x86 processor, and must be backward compatible. I am now having some issues with variable alignment. I have read the gcc manual for __attribute__((aligned(4),packed)) I interpret what is being said as the start of the struct is aligned to the 4 byte bo...
Hello, I need to change the the architectures of "Any iPhone OS Device" from "Optimized (armv6 armv7)" to "Standard (armv6)" for a library. I'm not exactly sure what effect will this have on the performance and stability of my iPad app. If I understand it right, the iPad has the armv7 architecture. I'm not so familiar with architectures,...
from ARM DDI 01001, there is a term: process geometry, does it mean the chip size? Caches and write buffers to improve average system performance are now commonplace in ARM® memory systems. Core clock rates have increased at a faster rate than memory access times over recent years. This factor, and smaller process geometries, the eco...
I'm receiving a SIGILL after running the following code. I can't really figure what's wrong with it. The target platform is ARM, and I'm trying to port a known library (in which this code is contained) void convertFloatToFixed(float nX, float nY, unsigned int &nFixed) { short sx = (short) (nX * 32); short sy = (short) (nY * 32...
I'm using an ARM7 core microcontroller. I'm unsure of how to calculate what T1LD register value to load to the timer to allow it to generate an IRQ every x ms. The only information that I can find in the documentation states "The timer interval is calcualted as follows" Interval = ((TxD)xPrescalar)/Source Clock I'm not sure...
I've to test some low level code on an ARM architecture. Typically experimentation is quite complicated on the real board, so I was thinking about QEMU. What I'd like to get is some kind of debugging information like printfs or gdb. I know that this is simple with linux since it implements both the device driver for the QEMU Integrator ...
This is specifically related to ARM Neon SIMD coding. I am using ARM Neon instrinsics for certain module in a video decoder. I have a vectorized data as follows: There are four 32 bit elements in a Neon register - say, Q0 - which is of size 128 bit. 3B 3A 1B 1A There are another four, 32 bit elements in other Neon register say Q1 ...
I'm writing for an atmel at91sam9260 arm 9 cored single board computer [glomation gesbc9260] Using request_mem_region(0xFFFFFC00,0x100,"name"); //port range runs from fc00 to fcff that works fine and shows up in /proc/iomem then i try to write to the last bit of the port at fc20 with writel(0x1, 0xFFFFFC20); and i segfault...specifi...
I am using an LPC2132 ARM chip to develop a program. However, my program has grown larger than the space on the chip. How can I connect my chip to some sort of external memory chip to hold additional executable code? Is this possible? If not, what do people normally do when they run out of chip space? ...
Hi everyone: I just begin to study ARM assembly language, and am not clear about how to use MOV to transfer an immediate number into a register. From both the ARM reference manual and my textbook, it's said that range of immediate number following MOV instruction is 0-255. But when I test on my own PC in ADS 1.2 IDE, instruction MOV ...
I've been programming for x86 & x86-64 in assembly language for few months. Now, I want to move on to some different kind of processors. MIPS, SPARC, PowerPC, Itanium, ARM of these I found ARM is being widely use. But the books I see that tutorials & books teach about MIPS more than all these other architectures. Why is MIPS so popul...
Hi everyone: I'm thinking about this question for a time: when does an ARM7(with 3 pipelines) processor increase its PC register. I originally thought that after an instruction has been executed, the processor first check is there any exception in the last execution, then increase PC by 2 or 4 depending on current state. If an exceptio...
Hello, I'm familiar with X86[-64] architecture & assembly. I want to start develop for an ARM processor. But unlike desktop processors, I don't have an actual ARM processor. I think I need an ARM simulator. http://www.armtutorial.com/ say An ARM assembly compiler will be required, the most accessible is the ARMulator. I thought o...
I am trying to compile a project to run on an ARM board that I have. To use the debugger, I have to put debugging symbols in the resulting .elf file. I configured everything and ran my makefile, which produced the following results: arm-elf-gcc -x assembler-with-cpp -c -mcpu=arm7tdmi-s -g -gdwarf-2 -Wa,-amhls=src/crt.lst src/crt.S -o...
I'm guessing MonoDroid compiles directly into ARM code. And the NDK, too. ...
I'm new to the embedded development world and am looking to get my very first board. After some research, I realize that there aren't many choices with FPUs. This is important in my project as I'm going to be doing quite a bit of floating point computations. I found the Mini2440 which seems to run on the ARM920T core. This particular u...
I need internet browser on my device which has 4.3 Inch screen with 480x272 resolution, I am using embedded Qt 4.6.2 on embedded linux. Micro-controller has ARM9 with 450 Mhz. Requirements for browser are - Touch Screen Support, Panning ( No Scroll bars) - Single touch Zooming ( No Multi Touch Available). - Fit to screen wid...
What is this selection for? I have the Architectures set to 'Optimized (armv6 armv7)' so a fat binary should be getting build with both, right? So why does this need to set this in the menu? What does it do? ...
I'm writing a Linux program that currently compiles and works fine on x86 and x86_64, and now I'm wondering if there's anything special I'll need to do to make it work on other architectures. What I've heard is that for cross platform code I should: Don't assume anything about the size of a pointer, int or size_t Don't make assumption...