I am a complete newbie to the ARM world. I need to be able to write C code, compile it, and then download into an ARM emulator, and execute. I need to use the GCC 4.1.2 compiler for the C code compilation.
Can anybody point me in the correct directions for the following issues?
What tool chain to use?
What emulator to use?
Are there tutorials or guides on setting up the tool chain?
building a gcc cross compiler yourself is pretty easy. the gcc library and the C library and other things not so much, an embedded library and such a little harder. Depends on how embedded you want to get. I have little use for gcclib or a c library so roll your own works great for me.
After many years of doing this, perhaps it is an age thing, I now just go get the code sourcery tools. the lite version works great. yagarto, devkitarm, winarm or something like that (the site with a zillion examples) all work fine. emdebian also has a good pre-built toolchain. a number of these places if not all have info on how they built their toolchains from gnu sources.
You asked about gcc, but bear in mind that llvm is a strong competitor, and as far as cross compiling goes, since it always cross compiles, it is a far easier cross compiler to download and build and get working than gcc. the recent version is now producing code (for arm) that competes with gcc for performance. gcc is in no way a leader in performance, other compilers I have used run circles around it, but it has been improving with each release (well the 3.x versions sometimes produce better code than the 4.x versions, but you need 4.x for the newer cores and thumb2). even if you go with gcc, try the stable release of llvm from time to time.
qemu is a good emulator, depending on what you are doing the gba emulator virtual gameboy advance is good. There are a couple of nds emulators too. GDB and other places have what appear to be ARMs own armulator. I found it hard to extract and use, so I wrote my own, but being lazy only implemented the thumb instruction set, I called mine the thumbulator. easy to use. Far easier than qemu and armulator to add peripherals to and watch and debug your code. ymmv.
Hmmm I posted a similar answer for someone recently. Google: arm verilog and at umich you will find a file isc.tgz in which is an arm10 behavioural (as in you cannot make a chip from it therefore you can find verilog on the net) model. Which for someone wanting to learn an instruction set, watching your code execute at the gate level is about as good as it gets. Be careful, like a drug, you can get addicted then have a hard time when you go back to silicon where you have relatively zero visibility into your code while it is executing. Somewhere in stackoverflow I posted the steps involved to get that arm10 model and another file or two to turn it into an arm emulator using icarus verilog. gtkwave is a good and free tool for examining the wave (vcd) files.
Above all else you will need the ARM ARM. (The ARM Architectural Reference Manual). Just google it and find it on ARM's web site. There is pseudo code for each instruction teaching you what they do. Use the thumbulator or armulator or others if you need to understand more (mame has an arm core in it too). I make no guarantees that the thumbulator is 100% debugged or accurate, I took some common programs and compared their output to silicon both arm and non-arm to debug the core.
Toolchain you can use Yagarto http://www.yagarto.de/
Emulator you can use Proteus ISIS http://www.labcenter.com/index.cfm
(There is a demo version)
and tutorials, well, google them =)
Good luck!
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I'm writing a teaching tutorial to teach university students and programming enthusiasts Compilation concepts on an x86.
I want an IDE tool like WinASM for them to be able to debug their work, but am aware that they may not all run Windows at home.
Is my best choice to target Jasmin? (Or have you got a better suggestion - and why?)
Another approach I've seen is to use a common teaching architecture (such as MIPS) and run it under emulation. For MIPS in particular, there are lots of interactive simulators (like SPIM), as well as full system emulators (like QEMU). The fact that the MIPS architecture is considerably simpler (and less register-starved!) than x86 is definitely a plus as well -- it means you can spend more time focusing on interesting compilation topics, rather than teaching the architecture.
This is another approach (although poor for debugging) - executing assembler inline in C++
A C repl that generates ASM - for learning about the assembler generated.
Also you could just rely on old gdb.
Have you ever considered an online debugging tool? There are a few of them out there. I personally like this asm debugger.
I'm pretty sure this is possible but I'm not sure how to go about it. I'm very new to building with GCC in general and I have never used FreeRTOS, but I'd like to try getting the OS up and running on a TI ARM Cortex MCU but with a slight twist: I'd like to get it up and running with Pascal. I'm curious:
Is this even possible to get work? If not, the next issues are kind of moot points.
From my Delphi days, I vaguely recall the ability to access functions in C libraries. I'm wondering if I would have access to the C routines in FreeRTOS.
If I use the GCC version (preferable) would I be able to debug using OpenOCD on the target? I'm not quite sure how debug symbols work and if it's more or less language agnostic (hopefully, in this case).
As kind of a bonus question a bit outside the scope of the original query, can I simulate FreeRTOS on an x86 processor (e.g. my development PC) for easier debugging during development? (With a Pascal program, of course..)
I haven't found any documentation on achieving this, so hopefully someone here can shed some light! Any resources would be most helpful. Like I said, I'm very new to this kind of development. I'm also open to suggestions if you think there is a better alternative.
FYI, my preferred host configuration would be something similar to:
Linux (Ubuntu/Debian)
Eclipse IDE for development, unit testing, and hopefully simulation / debugging
OpenOCD for target debugging
GNU Pascal + FreeRTOS on target
FreeRTOS is C source code, so like you say you would have to have some mechanism for linking C with your Pascal programs. Also, FreeRTOS relies on certain registers to be used for things like passing a parameter into a task (as a hypothetical example, the task might always expect the parameter to be in register R0) so you would have to ensure the ABI for the C compiler and the Pascal compiler was the same - or have your task entry in C then have it call a Pascal function (very nasty). Then there is the issue of interrupts, calling inline macros, etc. I would say this would be extremely difficult to achieve.
Both GNU Pascal and Free Pascal support linking to C (gcc) and ARM, as well as calling pascal code from C etc. Writing a header and declaring the prototypes with cdecl is all there is to it.
Macros are a bit bigger problem. Usually I just rewrite them to inline functions (what they should have been anyway). Except for the macro/header issue, the problems are more compiler specific functionality (which you also would have a problem with when porting from one C compiler to the next)
If you prefer TP/Delphi dialect, Free Pascal is the better choice.
I run my old Delphi code fine on my sheevaplug.
There is already an example for FreeRTOS/GCC/OpenOCD on a TI Cortex-M3 (was Luminary Micro Cortex-M3). Be aware though that this is a really old example and both the Eclipse and OpenOCD versions used are out of date.
Although there is an Eclipse project provided, the project is configured as a standard make (as opposed to a managed make) project, so there is a standard makefile that can be just as easily executed from the command line as from within Eclipse.
http://www.freertos.org/portLM3Sxxxx_Eclipse.html
I am on a Mac with Snow Leopard (10.6.3). I hear that the assembly language I work with has to be valid with the chipset that you use. I am completely new to this I have a basic background in C and Objective-C programming and an almost strong background in PHP. I have always wanted to see what assembly is all about.
The tutorial I'll be looking at is by VTC [link].
What I want to know is: are the tutorials that I'm about to do compatible with the assembly version on the Mac that I have?
I am completely new to this language although I do recall studying some of it way, way back in the day. I do have Xcode and what I'm wondering is what kind of document would I open in Xcode to work with assembly and does the Mac have a built in hex editor (when it comes time to needing it)?
The assembly language you use is not dependent on your OS but rather your CPU's instruction set. Judging by your Mac version, I'd say you are using an Intel processor - so you would want to learn x86 or amd64 assembly.
A good way to pick up assembly is to get yourself an embedded device to play with.
TI has some nice, inexpensive devkits to play with. I've poked around with the Chronos kit ($50) which has digital watch with a programmable MSP430 microcontroller with a wireless link to your computer. It's pretty sweet.
Update: I forgot to mention the Arduino. It's a pretty nifty open platform with tons of interesting peripherals and projects online.
An assembly language is instruction architecture specific. Chips are an instantiation of an instruction architecture.
In my opinion, you are best served by getting TextWrangler and directly compiling with gcc.
The file extension you are looking for is .s.
Assembly, for any processor, will be more or less the same in concept. However, the complexity varies between processors. From what I see in your site, you'd be doing x86 assembler, (x86 being the instruction set all consumer-line Intel processors use, which recent Macs and all PCs use) which can turn out to be fairly complex, but not overwhelming if you learn by steps.
XCode works with plain text files, I believe. Hex Fiend for your hex editing needs, if you come across them.
Do keep in mind, Assembly is extremely low-level. No ifs, whiles, or in fact any control loop save for "do operation and GOTO if results in (not) zero/equal" (unless your assembler provides them as syntactic sugar, which kind of beats the purpose, in my opinion). PHP knowledge will be at most tangentially useful. You C knowledge should serve you well, though.
The linked tutorials look like they use NASM, which is included with Macs. However, system calls are usually different on different platforms (they're very different between Mac and Linux), and without seeing the tutorials, it's hard to know whether they'll target different platforms (I'd guess not, though). A better bet might be to install SPIM and to learn MIPS assembly, which is more straightforward than x86 anyways.
Okay. I want to learn how to assemble programs on my Mac (Early 2009 MBP, Intel Core 2 Duo). So far, I understand only that Assembly languages are comprised of direct one-to-one mnemonics for CPU instructions. After some Googling, I've seen a lot of terms, mostly "x86" and "x86_64". I've also seen MASM, NASM, and GAS, among others.
Correct me if I'm wrong:
x86 and x86_64 are instruction sets. If I write something using these instruction sets (as raw machine code), I'm fine so long as my program stays on the processor it was designed for.
NASM, MASM, and GAS are all different assemblers.
There are different Assembly languages. There's the AT&T syntax and the Intel syntax, for example. Support for these syntaxes differ across assemblers.
Now, questions:
As a Mac user, which instruction sets should I be concerned about?
Xcode uses GCC. Does this mean it also uses GAS?
If it does use GAS, then should I be learning the AT&T syntax?
Is there a book I can get on this. Not a tutorial, not a reference manual on the web. Those things assume to much about me; for example, as far as I know, a register is just a little bit of memory on the CPU. That's how little I really know.
Thanks for your help.
If you want to learn assembly language, start with the x86 instruction set. That's the basic set.
A good book on the subject is Randall Hyde's the Art of Assembly Language, which is also available on his website. He uses a high-level assembler to make things easy to grasp and to get going, but deep down it uses GAS.
I don't believe that XCode comes with any assembler, but you can for example find GAS in MacPort's binutils package.
If you just want to make programs on your Mac and you're not that interested in the life of all the bits in the CPU, you're much better off with a more high-level language like Python or Ruby.
"I'm fine so long as my program stays on the processor it was designed for." Not really. In many cases, assembler programs will also make assumptions about the operating system they run on (e.g. when they call library functions or make system calls). Otherwise, your assumpptions are correct.
Onto questions:
Current Macs support both x86 and x86-64 (aka AMD64 aka EM64T aka Intel64). Both 32-bit and 64-bit binaries can be run on recent systems; Apple itself ships its libraries in "fat" (aka "universal") mode, i.e. machine code for multiple architectures.
Use "as -v" to find out what precise assembler you have; mine reports as "Apple Inc version cctools-698.1~1, GNU assembler version 1.38". So yes, it's GAS.
Yes.
https://stackoverflow.com/questions/4845/good-x86-assembly-book
I'll answer the first question:
Macs use Intel chips now, and modern processors are 64-bit.
Note: I know very little about the GCC toolchain, so this question may not make much sense.
Since GCC includes an Ada front end, and it can emit ARM, and devKitPro is based on GCC, is it possible to use Ada instead of C/C++ for writing code on the DS?
Edit: It seems that the target that devKitARM uses is arm-eabi.
devkitPro is not a toolchain, compiler or indeed any software package. The toolchain used to target the DS is devkitARM, one of the toolchains provided by devkitPro.
It may be possible to build the ada compiler but I doubt very much if you'll ever manage to get anything useful running on the DS itself. devkitPro will certainly never provide an ada compiler as part of the packages we produce.
Yes it is possible, see my project https://github.com/Lucretia/tamp and build the cross compiler as per my script. You would then be able to target NDS using Ada. I have build a basic RTS as well which will provide you with local exception handling.
And #Martin Beckett, why do think Ada is aimed squarely at DoD stuff? They dropped the mandate years ago and Ada is easily usable for any project, you do realise that Ada is a general purpose programming language don't you?
(Disclaimer: I don't know Ada)
Possibly.
You might be able to build devKitPro to use Ada, however, the pre-provided binaries (at least for OS X) do not have Ada support compiled in.
However, you will probably find yourself writing tons of C "glue" code to interface with the various hardware registers and the like.
One thing to consider when porting a language to the nintendo DS is the relatively small stack it has (16KB). There are possible workarounds such as swapping the SRAM stack content into DRAM (4MB) when stack gets full or just have the whole stack in DRAM (assumed to be auwfully slow).
And I second Dre on the fact that you'll have to provide yourself glue between the Ada library function you'd like to use and existing libraries on the DS (which are hopefully covering most of the hardware stuff).
On a practical plane, it is not possible.
On a theoretical plane, you could use one custom Ada parser (I found this one on the ANTLR site, but it is quite old) in order to translate Ada to C/C++, and then feed that to devkitpro.
However, the effort of building such translator is probably going to be equal (if not higher) to creating the game itself.