Big-Endian vs. Little-Endian

Started by Everett M. Greene in comp.arch.embedded13 years ago 69 replies

At the risk of starting a flame war, which choice have people really made with regard to Little-Endian vs. Big-Endian for those processors where...

At the risk of starting a flame war, which choice have people really made with regard to Little-Endian vs. Big-Endian for those processors where it's a design choice (ARM, PowerPC,...)? I'm asking in the context of using such processors in embedded applications where compatibility with anything in the outside world is not a factor.


Endianness does not apply to byte

Started by karthikbg in comp.arch.embedded11 years ago 91 replies

Hi, I find that regardless of what the byte Endian order is, the bits within bytes are always in Big-Endian format. For instance, 1 is...

Hi, I find that regardless of what the byte Endian order is, the bits within bytes are always in Big-Endian format. For instance, 1 is always stored in a byte as 000000012 no matter what platform. But, this is in violation to the Endianness concept as little endian internally a big-endian. (Bits within Bytes) So, this implies that Big-Endian is the better concept and why did they ...


Change endian

Started by qwertz911 in comp.arch.embedded9 years ago 4 replies

Hello, i am new with ARM and i found one problem. I really need change endian from little to big. I think that its changing in startup with...

Hello, i am new with ARM and i found one problem. I really need change endian from little to big. I think that its changing in startup with function: OUTPUT_FORMAT("elf32-littlearm", "elf32-littlearm", "elf32-littlearm") but when i change it to "elf32-bigarm", compiler report problem, that he cannot compile anything because ld.exe is little endian. Please tell me how to change endian or a...


IXP425 Little Endian/ Big Endian

Started by A Beaujean in comp.arch.embedded13 years ago 1 reply

Having developed a new IXP425 based card, we now face the problem of writing the BSP for it. Actually, the main problem at this very moment is...

Having developed a new IXP425 based card, we now face the problem of writing the BSP for it. Actually, the main problem at this very moment is understanding the real issues with Endianess. Indeed, primary tests made with the ARM MultiIce emulator appear to clearly indicate that Big Endian is required if wanting to access the IXP425 expansion bus with correct addressing (bytewise or wordw...


Testing little/big endian issues on an Intel PC

Started by Sachin Garg in comp.arch.embedded10 years ago 7 replies

I need to test code for some compression algorithms for any possible little/big endian issues that I might have left in there. As...

I need to test code for some compression algorithms for any possible little/big endian issues that I might have left in there. As development was done on an Intel desktop, what is the best way to test it out without having to buy big-endian hardware. Can some emulator etc be used for this? The code is fairly portable (basic C++, mostly maths, and some file reading/writing) and can be b...


Little endian on IO output

Started by Steven P in comp.arch.embedded11 years ago 8 replies

Good Morning: I have a project using a 32bits little endian processor but with only 16 bits data bus. How will it behave when it puts data on...

Good Morning: I have a project using a 32bits little endian processor but with only 16 bits data bus. How will it behave when it puts data on the data bus. also in little endian mode? And if the data type has length longer than the IO Data bus, how will it normally behave? Does endianness only relate to memory? Example. short int a = 0x2211, will it puts data with the same order on dat...


PowerPC MPC5200B, changing mode to run in little endian

Started by Taran in comp.arch.embedded10 years ago 1 reply

Hi, We are using Lite5200B eval board, out software is compiled using the Windriver diab 5.3.1.0 with the 5200B patch. We are using...

Hi, We are using Lite5200B eval board, out software is compiled using the Windriver diab 5.3.1.0 with the 5200B patch. We are using the WindRiver ICE for downloading the executable to the board and stepping through. We have our software with the MPC5200B running in default big endian mode. Because the PCI bus is little endian mode we are evaluating the impact on software if we switch th...


Floating point numbers and endian ness??

Started by ssubbarayan in comp.arch.embedded10 years ago 21 replies

Hi, I was going through wikipedia about endians.I got the below description with respect to floating point numbers: "On some machines, while...

Hi, I was going through wikipedia about endians.I got the below description with respect to floating point numbers: "On some machines, while integers were represented in little-endian form, floating-point numbers were represented in big-endian form. [3] Because there are many floating formats, and a lack of a standard "network" representation, no standard for transferring floating point val...


AVR Harvard architecture -- worst of both worlds?

Started by Everett M. Greene in comp.arch.embedded10 years ago 29 replies

And we won't even get into Little-Endian vs. Big-Endian... An "interesting" situation arises when dealing with constants in programs. One...

And we won't even get into Little-Endian vs. Big-Endian... An "interesting" situation arises when dealing with constants in programs. One would like to put these in ROM but with a Harvard architecture, one can't access the locations as directly (if at all) as one can if the values are in RAM. Thus, one has to have either special functions to call to copy the constants to RAM when needed or...


.rodata format in elf

Started by Anonymous in comp.arch.embedded11 years ago

hai all... my purpose is to parse an ELF file in order to obtain the values of some constants(read only data)... i have acessed the .rodata...

hai all... my purpose is to parse an ELF file in order to obtain the values of some constants(read only data)... i have acessed the .rodata section..what i want to know is, while calculating the CRC of that particular data obtained form the .rodata section will be same for both little endian and big endian formats.. regards sreeraj


Endianess problem

Started by sid1977 in comp.arch.embedded10 years ago 4 replies

Hi, I am writing a driver for a ethernet controller. The controller is connected to the io memory and expects data to be in the Little...

Hi, I am writing a driver for a ethernet controller. The controller is connected to the io memory and expects data to be in the Little endian format (will call it LE now and BE for big endian). The main cpu which runs the driver code is a BE machine. During the startup I write the descriptors into the io memory in the LE format. In the send and receive routine which is called by the IP stack I...


VME and Big Endian

Started by Mark_Galeck in comp.arch.embedded10 years ago 1 reply

Hello, I want to access from a Big endian CPU, a VME bus peripheral card. Let's say for example, I want to write a value that ends up in a...

Hello, I want to access from a Big endian CPU, a VME bus peripheral card. Let's say for example, I want to write a value that ends up in a register on the card, at address 0x2, in the register I want to have 0x1234, in other words, in bits 0-7 of the register I want to have 0x34, and in bits 8-15, I want to have 0x12. And suppose I want to do this with a 16-bit bus write operation from the...


arm11/armv6 right shift signed packed values

Started by Anonymous in comp.arch.embedded9 years ago 3 replies

I'm attempting to pack some numbers for output after doing some work. They're currently r7 = v0|v4 and r10 = v1|v5. They all need to be > >...

I'm attempting to pack some numbers for output after doing some work. They're currently r7 = v0|v4 and r10 = v1|v5. They all need to be > > 3, before or after repacking. Output will be v1|v0 and v5|v4 (little endian architecture). I managed to get the v1|v0 written reasonably efficiently: mov r8, r10, asr #3 ; 1> > 3|xxx pkhtb r8, r8, r7, asr #19 ; 1> > 3|,0> > 3 str r8, [r0], r2 ; o1|o0, post


attempting to troubleshoot for customer

Started by Tier3 in comp.arch.embedded11 years ago

This little poor thing looks just odd. When you take a closer look, you will see that port numbers and other TCP parameters of this packet are...

This little poor thing looks just odd. When you take a closer look, you will see that port numbers and other TCP parameters of this packet are actually... constructed of what should be the packet payload! Source port and destination port, two 2-byte values that start every TCP header, are 18245 and 28261 - 0x4745, 0x5420 in network endian order. This translates to ASCII string 'GET ', a ...


Alchemy AU1550 board: establish endianness

Started by Roman Mashak in comp.arch.embedded13 years ago 3 replies

Hello, All! Could you please explain me the process of establishing the endianness on Alchemy board? This board has the DIP switches for...

Hello, All! Could you please explain me the process of establishing the endianness on Alchemy board? This board has the DIP switches for establish endian mode, and I'd like to understand how to determine the endianness from software. On-board CPU is MIPS32. With best regards, Roman Mashak. E-mail: mrv@tusur.ru


LPC2478 LCD controller intensities and modulation rates

Started by Valio Simitrov in comp.arch.embedded6 years ago

Hello, i have a board with LPC2478 and 320x240 STN LCD. The LCD mode is set to 4bpp, Mono, STN, Little Endian byte and pixel order. I have...

Hello, i have a board with LPC2478 and 320x240 STN LCD. The LCD mode is set to 4bpp, Mono, STN, Little Endian byte and pixel order. I have initialized the palette with these values: b31 b0 hex address 0b0000000000000010 0000000000000000 0x00020000 0xFFE10200 0b0000000000000110 0000000000000100 0x00060004 0xFFE10204 0b0000000000001010...


Little Endian: What would be the no stroed at memory location 0x0001

Started by 2005 in comp.arch.embedded11 years ago 5 replies

Hi It is given that the number 0x0abc1234 is stored in a four-byte integer, starting a location memory 0x0000. What would be the no stroed...

Hi It is given that the number 0x0abc1234 is stored in a four-byte integer, starting a location memory 0x0000. What would be the no stroed at memory location 0x0001? Thanks


Newbie: arm-elf-gcc generated asm question

Started by Ken Barlow in comp.arch.embedded13 years ago 10 replies

Hi, I have started evaluating the GNUARM tools for a LPC210x target (little-endian) and come across the following which is odd to me. With...

Hi, I have started evaluating the GNUARM tools for a LPC210x target (little-endian) and come across the following which is odd to me. With ul defined as: unsigned long *ul; The function function1 returns a pointer to void. For the following line, ul = ( unsigned long * ) function1(); GCC uses R0 to return the function1() result which is 0x40000625, the instruction: STR R0, [R4,#0...


Wishbone, TSK3000 and endianness problem

Started by argee in comp.arch.embedded10 years ago

Hi all, I'm working on interfacing a custom IP core to a TSK3000 (Altium's P/H:MIPS-like soft processor) over WISHBONE bus and it seems I've...

Hi all, I'm working on interfacing a custom IP core to a TSK3000 (Altium's P/H:MIPS-like soft processor) over WISHBONE bus and it seems I've run into some endianness problems. I've always been confused by endianness issues and now, after a few days of debugging both hardware and software, my head is ready to explode. The TSK3000's datasheet states that the processor uses only BIG endian ...


Defining the endianness for arm7 MCU

Started by Daniel in comp.arch.embedded14 years ago 2 replies

Hi there, I am struggling with a problem on my lh75411 MCU (arm7) which concerns the endianness. I observed that the endianness changes...

Hi there, I am struggling with a problem on my lh75411 MCU (arm7) which concerns the endianness. I observed that the endianness changes sometimes when uploading a srec file after reset to the MCU. I am using the following script for the M*craigor OCD tool: conn endian little CPSR = 0x13 r13 = 0x2100 r14 = 0x2200 byte 0xfffe2008 = 0x01 word 0xfffe5000 = 0x00005B3F wor...