I would like to try some ARM assembly code with apple iOS just for educational purpose. I would like to start with some in line code within Xcode.
My understanding is that I need to compile for a iOS device, for example for my iPhone, which means that I need to pay $99/year for membership.
I don't think I can use ASM assembly code with a iOS phone simulator.
I am having an hard time on finding examples, books or documentation on ARM assembly code in Xcode env with an iPhone.
Am I doing this wrong? Maybe iOS is not the most user friendly environment to learn ARM Assembly.
Back up...
What are you trying to learn? Arm assembly or iOS programming? Pick one...
Do you have any assembly experience?
What is it you think you are wanting to learn in arm assembly? Jump in and write some full blown gui applications? You need to learn to put immediates in registers add and or and xor and save answers in registers. then read and write some memory locations. Learn to use the stack, make calls, etc. Then write your applications in C or whatever and use asm for hand tuning or use your asm skills to debug the compiler and or code. Writing applications or operating systems, etc in asm is for folks who want to make a statement, or have a specific reason, not for educational purposes.
There is some leaning toward a unified ARM assembly language that works both on the ARM based cores and the thumb2 based cores. Not for all of the assembly language needed but for places where you might want to write a module of code and not have to have a lot of if thumb elses littering the code. You can certainly get your feet wet with that here and take some of that code straight to full 32 bit ARM instructions on some other platform. thumbulator is thumb only, the common instruction set between the ARM based cores and the thumb2 based cores, basically it is the portable ARM instruction set, write the code once, it works on almost all of their cores.
If your goal is to learn iOS programming, get the kit or whatever and learn using whatever language they want you to learn, get proficient at that, learn the apis, etc. Then if you do some of the assembler stuff above then you can start to think about making calls to asm functions or inline assembler, etc, from your iOS programs. How much assembler, your choice. I wouldnt expect to see applications written in assembler for that platform I would instead search for how do I call this assembly code from my ios application or how do I do inline assembly. (dont learn inline assembly until you are good at real assembly).
There is no reason at all to pay for access to a simulator, there are many many arm simulators out there, one in mame, arms armulator in gdb and other places, a number of gameboy advance and nintendo ds simultators, etc, etc, etc. Of course there is qemu-arm. there are more simulators than you probably are willing to take the time to try, i am about 10 years or so into it myself and not tried them all.
learning assembly is not like C or python or java, I will write a minesweeper game to learn this language. You are learning the mechanics of moving the bits around, small steps, not writing usable applications. For example adding two 128 bit numbers using a 16 bit processor is a worthy assembly language project. Multiplying two numbers, any size, with a processor without a multiply instruction, that is another assembler type learning project. yes, I agree you CAN learn those things by calling asm from an iOS application, but if you dont already have the iOS developers kit and know how to write iOS applications, you have a lot of learning to do before you start thinking about assembler.
If I am way off the mark with what you were asking, no problem I will gladly remove this answer...
Even without a code signing cert, I think you should be able to go to the scheme pop-up menu (the right side of it) and choose "iOS Device"
Once you do that, then you can choose any .c or .m (or .cpp or .mm) file in your project, open the assistant editor, and choose "Assembly" from the assistant editor jumpbar. Then you can see your source code and assembly code side by side.
Or you can just go to Product menu and Generate Output -> assembly
You may find it easier to start with C code, where the function calls will be much easier to follow initially than Objective-C method calls.
What you need is an ARM development kit with a Linux-based programming toolkit. You can then install VirtualBox on your Mac, create a Linux virtual machine and install the ARM development tools on the virtual Linux machine. Make sure that when you buy an ARM dev kit, it comes with the ARM cpu, complete dev/test board, USB cables for software transfer/debugging and the complete Linux toolchain. You can find such kits for less than $99.
Another quick introduction to ARM assembly and reverse engineering: http://yurichev.com/writings/RE_for_beginners-en.pdf
Related
By checking the Codename One website and ParparVM Github, its guide only show how to build the Java (with Java Main function entry point) into the native executable/app (iOS), but I can't find any guide to build/compile Java into iOS share library (either in C source or binary, as long as can be reused by swift/objective-C from iOS app).
So are we able to do so? is there any guide for that?
It wasn't designed for that purpose so it probably won't work well for it. There are some inherent design decisions that would make it very difficult to get ParparVM to work with a library. Two big ones:
The GC needs to work with roots and would have a hard time collecting without full control of the app
The code generated looks "awful". Method names translate to very long function names in C with a very convoluted syntax to allow all sort of VM edge cases such as covariance
I suggest you look at J2ObjC. I haven't checked it out in ages but it was designed exactly with this use case in mind. It doesn't have a "real" GC but that might be OK with ARC. It works with your sources and produces libraries that look a bit more "natural" on iOS.
I'm interested is it possible to install and use Android Things(former Brillo) on custom produced hardware?
I can see from the official documentation there is preselected and certified SoMs listed, but I'm interested in using my own hardware.
Is it possible to have best of both worlds - use the familiar to me Android & Android Things but run it on proprietary hardware?
If not, what other options do I have - I researched about micropython, but apparently it seems it also comes with designated board(pyboard).
So my question is what are options to not thinks too much about the firmware on the device(and write C code), but focus on more higher-level business logic and programming languages(Java, Python).
Android Things isn't open source, so you can't put it into that isn't officially supported.
If you're looking for custom options, you will need to find a compiled language like C that works for that board. While C may be a bit intimidating, you may be able to find languages that compile to similar machine code. Rust and Go may work on microcontrollers too if you check.
I'm not too familiar with micro python. It says that it compiles to bare metal/machine code, so I believe you should be able to use it on other boards. While they may officially support the compiler for one board, the community may have support for additional microcontrollers.
I've been searching for some information regarding microcontroller programming but the info I find is either way over my head or doesn't appear to exist. I'm looking for something easier to digest! I'm relatively new to programming and come from an SQL DBA background and decided that it would be quicker for me to learn some programming fundamentals and then teach myself Delphi than it would to get some changes implemented through my company's insane design change note system!
After a couple of years of Delphi programming I can cope with writing database applications without too much bother and I want to be able to move on a level.
We use PIC microcontrollers on our PCBs; mainly the PIC18F family. The software on the PICS is written in C but there are parameters values that are written to by a Delphi application that interface with the PIC using an ActiveX control.
Basically, SQL Database holds parameter info, Delphi client app retrieves those values, passes them to the ActiveX controll which does all the low level stuff on the PIC. For example the internal EEPROM will have a map and within any particular address a value will be stored to switch something on or off or hold an integer value etc.
I've gotten hold of an MPLAB kit which has an ICD2 device that can read and write values to the internal EEPROM and I understand how to change these hexadecimal values using MPLAB software.
My hope isn't to learn embedded microcontroller programming; rather that I can write a Delphi app that will do something similar to MPLAB software. E.g read and write values to certain memory addresses within the EEPROM.
I'd be very gratefull if anyone can point me in the right direction of any libraries or components that may already exist for bridging this gap between simple Delphi form application and writing low level PIC EEPROM. I doubt such any easy interface exists but I thought I'd ask. To summarise I want to be able to have a simple form app, with some edit boxes that the user types in or selects from dropdown boxes, parameter values, to click on a button and to assign those parameter values to specific EEPROM memory addresses. Thank you for reading and any comments would be gratefully received.
Regards
KD
I'm a big fan of MikroElectronika and have used their Pascal tools for pic16 series MCU with great success (touch screen interfaces, ZigBee, ...).
http://www.mikroe.com/
Updated 2015 Answer:
Why not a Raspberry Pi with FreePascal and Lazarus? The boards cost from $5 to $25 US, as of this date, and the development tools are free.
Original 2012 Answer:
If you like to use Pascal, you might find Free Pascal useful on small embedded systems, but the minimum I believe you will find it can compile on is a Linux-based ARM embedded system. The fact that you use pascal on both sides is very unlikely to help you accomplish anything major.
If you want to go all the way down the the smallest PIC microcontrollers, you'll find that it's almost always a variant of C that you'll be using. Frankly, at that level, the differences aren't that much. If you can write Pascal, you can learn enough C in a day, to use with microcontrollers.
Don't be scared to use the native language that most microcontrollers support. My personal favorites are the Rabbit microcontrollers, formerly from Z-World, now from digi -- I think I paid about $100 US for the first board and development toolkit.
Interfacing such an application with delphi is pretty easy, usually these days, I would interface using TCP/IP over either wired Ethernet, or wireless (Wifi). But if you really want to you could use RS-232 or RS-485 serial links. (RS-485 has the advantage that you can wire it up to 5 miles long.) If I was using a serial link, I'd probably implement something like Modbus on both sides, if I just wanted to send some numeric data back and forth, and if I was doing something text-oriented, I think I'd write a mini HTTP web server on the embedded controller, and most boards these days come with enough HTTP server demos to make that drop-dead easy.
Delphi outputs Win32 and Win64 native applications you can write software that can interact with certain devices if the PCB has serial comunication or I2C you can write software that in Delphi that it will interact with the physical device.
But if you want to programm the devices yourself , write software that will run on this devices you can't do it in Delphi. I suggest you buy an Arduino it's an excellent envoirment for beginners in microcontroller programming.
If you have the source code of your pic microcontroller then you can implement the code in C to read from Serial, USB or some other interface available in your hardware and write it to the eeprom. This way its easy to write the app in any high level language like delphi, c++, etc.
Or you can write your PIC application using the mikropascal compiler from mikroeletronika that its very good and I've been using for a long time, but as you can see you will have to implement some mecanism to read from the interface and write to your eeprom as I've mentioned before.
This compiler comes with a lote of librarys to work with many devices. You should take a look on it, its not free but the price is low and in their site you can find samples and sample boards to test it.
One option, if you want a simple interface to write to the PIC EEPROM, is to use the ICD command line utility. Unfortunately it is not available for the ICD2, but the PICkit 2 and 3 (which are cheap), ICD3, and RealICE have command line utilities that give you the ability to write to the EEPROM (google pk2cmd). In Delphi, you could just wrap a very simple set of command line calls to pk2cmd.
I want to port a good OpenCV code on an embedded platform. Earlier such stuffs were very difficult to perform but now TI has come up with nice embedded platforms which are comparatively hassle free as they say.
I want to know following things:
Given that :
The OpenCV code is already running on PC smoothly. (obviously)
Need to determine these before purchasing the device.
Can't put the code here in stackoverflow. :P
To chose from Texas Instruments: C6000.
Questions:
How to make it sure that the porting will be done?
What steps to be taken to make it sure that after porting the code, will run (at least).
to determine whether the code might require some changes to make its run smooth.
The point 3 above is optional.
I need info which will at least give me some start up in this regard.
What I thought I should do?
I am to list the inbuilt functions down.
Then to find available online bench marking for those functions for the particular device like as shown towards the end of this doc.
...
Need to know how to proceed further?
However C6-Integra™ DSP+ARM Processor seems the best.
The best you can do is to try a device simulator (if it is available), but what you'll see there is far from perfect.
Actually, nothing can tell you how fast and how well the app will run on the embedded device before running you specific app on that specific device.
So:
Step 1 Buy it
Step 2 Try it
Things to consider:
embedded CPU architecture: Your app needs a big cache? how big is the embedded cache?
algorithm: do you use a lot of floating point operations? how good is the device at floating point ops?
do you have memory transfers? data bus on a PC is waaay faster than on embedded
hardware support: do you use a lot of double-precision calculations? they are emulated on ARMs. They are gonna kill your app (from millisecons on a PC it can go to seconds on a ARM)
Acceleration. Do your functions use SSE? (many OpenCV funcs are SSEd, even if you don't know). Do you have the NEON counterpart? (OpenCV does not have much support for that). The difference can be orders of magnitude from x86 SSE to embedded without NEON.
and many, many others.
So, again: no one can tell you how it will work. Just the combination between the specific app and the real device tells the truth.
even a run on a similar device is not relevant. It can run smoothly on a given processor, and with another, with similar freq or listed memory, it will slow down too much
This is an interesting question but run is a very generic word in this context, therefore I feel the need to break it down to other 2 questions:
Will it compile in an embedded device?
Will it run as fast/smooth as in a PC?
I've used OpenCV in a lot of different devices, including ARM, SH4, MIPS and I found out that sometimes the manufacturer of the device itself provides a compiled version of OpenCV (for my surprise), which is great. That's something you can look into, maybe the manufacturer of your device provide OpenCV binaries.
There's no way to know for sure how smooth your OpenCV application will be on the target device unless you are able to find some benchmark of OpenCV running in there. PCs have far better processing power than embedded devices, so you can expect less performance from the target device.
There are 3rd party applications like opencv-performance, that you can use to test/benchmark the environment once you get your hands on it. And if performance is such a big deal in this project, you might also be interested in this nice article which explain some timing tests done on couple of OpenCV features comparing implementations using the C and C++ interfaces of OpenCV.
I've been reading about Andrew Russell's ExEn project and I'm wondering what the flow would be like for creating a WP7 accelerometer-based game and then porting it to another platform, say iOS. Here's what I hope would happen:
Create fully functional game in XNA, avoiding dependance on device
specific items like the 'back' button.
Run the project through ExEn (I have no idea on how this would
happen), creating fully functional iOS game.
Run game on iPhone.
Sorry for that pitiful outline, but I just don't have a solid high-level view after reading about it.
Also, being software conversion, surely it wouldn't totally work. How would you iron out the wrinkles? I assume you'd have to know iOS or Android fairly well to pin it down.
Anyway, if anyone can move me one step closer I would appreciate it.
ExEn is an implementation of a subset of the XNA API that runs on different platforms (including iOS and Android). Put simply, it makes the classes and methods that you use when writing XNA code available to you on these other platforms. (Plus appropriate instructions, examples, etc.)
When using ExEn, the bulk of your code should simply "just work". However in most real-world cases you will need to write at least some platform-specific code (and probably provide some platform-specific assets). In particular to support different device resolutions, and also in cases where you use XNA features not available in ExEn.
At time of writing, ExEn does not implement the XNA/WP7 APIs for accelerometer support. At some time in the future they may be added (either by me or anyone who wants to contribute a patch). ExEn is distributed as source code, so you could even add the necessary support yourself.
The alternative would be to write platform-specific code for the parts of your game that query the accelerometer. Using ExEn does not prevent you from also using the APIs of the underlying platform.
ExEn (on iOS and Android) runs on top of Xamarin's MonoTouch and Mono for Android products. These two products provide C# bindings for the underlying platform APIs. Also, much like ExEn implements the XNA APIs, Mono implements the .NET APIs. These products also provide you with the tools you need (IDE, compiler, debugger, etc).
So the iOS API that you would use is UIAccelerometer (doc). This is exposed in C# via MonoTouch.UIKit.UIAccelerometer (doc). I'll leave looking up the Android equivalents as an exercise.
You can't expect:
porting a game to other platform and don't modify it.
porting a game with special platform inherent abilities to other platform that lacks this abilities, or vice versa