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by jahboater
Mon Jul 29, 2019 10:18 pm
Forum: General discussion
Topic: Learning Assembler on the Pi
Replies: 51
Views: 1519

Re: Learning Assembler on the Pi

All I always wanted/needed was C but with all the undefined behaviors and other surprises fixed. There should not be any surprises. Annex J in C18 has a complete and definitive list of: Unspecified behavior, Undefined behavior, and Implementation defined behavior. Newcomers to the language would do...
by jahboater
Mon Jul 29, 2019 5:48 pm
Forum: General discussion
Topic: Learning Assembler on the Pi
Replies: 51
Views: 1519

Re: Learning Assembler on the Pi

Heater wrote:
Mon Jul 29, 2019 5:07 pm
where one is pretty much forced into object oriented programming, Java, C#, C++.
Java yes, but not C++.
C++ is multi-paradigm. Mr Stroustrup gets most upset if you call it an object oriented language.
by jahboater
Mon Jul 29, 2019 11:26 am
Forum: General programming discussion
Topic: Liberation through Computer Literacy
Replies: 1085
Views: 40712

Re: Project Digital Apocalypse Not Now

Is there a proper islower() function in Rust? (like ctype.h in C)?
Perhaps the method:

is_ascii_lowercase()

or at least the equivalent of

return (c >= 'a' && c <= 'z');
by jahboater
Mon Jul 29, 2019 10:46 am
Forum: General discussion
Topic: Raspberry pi for coding on machine level?
Replies: 31
Views: 1233

Re: Raspberry pi for coding on machine level?

I was wondering if C can generate (rather than the binary) a file that's readable in assembler. Yes, use the -S option of the gcc compiler. Yes. If you use Raspbian Buster, it comes with a more recent version of GCC (8.3) that can include the original C source code within the assembler file. That m...
by jahboater
Sun Jul 28, 2019 5:41 pm
Forum: General discussion
Topic: Learning Assembler on the Pi
Replies: 51
Views: 1519

Re: Learning Assembler on the Pi

A lot of people made videos on the Pi 4 idling temperatures being very hot, Yes, they put them in plastic cases with no holes. Not the cleverest thing to do with a SoC that may produce up to 9W of heat. Although there are some videos explaining a FW update, that would remove the heat issue resultin...
by jahboater
Sun Jul 28, 2019 5:25 pm
Forum: General discussion
Topic: Learning Assembler on the Pi
Replies: 51
Views: 1519

Re: Learning Assembler on the Pi

I read up on the Pi's idle temperatures, they're somewhere in the 60C, reaching throttling temps of 83c in a mere few seconds. You should get a Pi4 yourself and try it. My Pi4 is in free air with NO FAN , it idles at around 44/45C on this warmish day in the UK. Time Temp CPU Core GPU Health Vcore 1...
by jahboater
Sun Jul 28, 2019 5:12 pm
Forum: General discussion
Topic: Learning Assembler on the Pi
Replies: 51
Views: 1519

Re: Learning Assembler on the Pi

Pi 3B+ (2 Gig model): $37 I think you will find there never was a 2GB Pi3 model - 1GB only. To compare prices, you must compare the 1GB Pi3 to the 1GB Pi4, like for like - sort of. Except that the Pi4 has 3200MHz DDR4 memory, the Pi3 had 450Mhz DDR2 memory. The Pi4 has full speed GiGe ethernet, USB...
by jahboater
Sun Jul 28, 2019 2:28 pm
Forum: General discussion
Topic: Learning Assembler on the Pi
Replies: 51
Views: 1519

Re: Learning Assembler on the Pi

Thing is they tried multiple times to introduce completely new ISA's and it always failed.
Users want backwards compatibility.

Anyway, I'll await RISC-V catching up so that you can add "convolutional neural network" instructions to your FPGA :)
by jahboater
Sun Jul 28, 2019 1:24 pm
Forum: General discussion
Topic: Learning Assembler on the Pi
Replies: 51
Views: 1519

Re: Learning Assembler on the Pi

And it is far from modern. What about all the new instructions being added now ? As advanced/modern as it gets. There is lots of cryptography stuff (AES and Galois Field insns) but I thought these might be interesting for @Ejolson:- "four new instructions for accelerating inner convolutional neural...
by jahboater
Sun Jul 28, 2019 11:47 am
Forum: General discussion
Topic: Learning Assembler on the Pi
Replies: 51
Views: 1519

Re: Learning Assembler on the Pi

I'm not sure that's true for the large, modern 64-bit instruction sets. In general, I find the modern large instruction sets far easier to use. There is much more likely to be an instruction or addressing mode to do what you want, without you having to do it by hand. A obvious example, the Pi 1 and...
by jahboater
Sun Jul 28, 2019 10:03 am
Forum: Advanced users
Topic: RPi4 memory transfer (can it be faster?)
Replies: 2
Views: 206

Re: RPi4 memory transfer (can it be faster?)

There are other instructions. LDM/STM are supposed to be slow on a modern out-of-order CPU like the Cortex-A72. (which is why they were removed for 64-bit mode). There is also LDRD/STRD (double registers) In Aarch64, I had the best results with LDP Q0,Q1 ... / STP Q0,Q1 ... which move 32 bytes at a ...
by jahboater
Sat Jul 27, 2019 12:21 pm
Forum: General discussion
Topic: Why is the RPi4 being advertised as a desktop computer?
Replies: 114
Views: 9751

Re: Why is the RPi4 being advertised as a desktop computer?

The Pi will remain a hobbyist computer with commercial applications until stability of the system is addressed. We shouldn't be even having this conversation - it's one from 20 years ago. OK, I don't (at the moment) use my Pi for all the stuff you do, I just use them for software development. I do ...
by jahboater
Sat Jul 27, 2019 11:31 am
Forum: Raspbian
Topic: Change raspbian looks, easy to do?
Replies: 6
Views: 305

Re: Change raspbian looks, easy to do?

ProDigit wrote:
Sat Jul 27, 2019 11:14 am
Thanks!
Does Raspbian have the ability to have a black taskbar (like Windows Vista, or Lubuntu 19.04)?
Yes. In the same "Taskbar" menu, you can set the colours.
by jahboater
Sat Jul 27, 2019 11:28 am
Forum: General discussion
Topic: Learning Assembler on the Pi
Replies: 51
Views: 1519

Re: Learning Assembler on the Pi

ProDigit wrote:
Sat Jul 27, 2019 11:22 am
In any case, the Pi 3 is just perfect.
Well make sure you get a 3B+ (with the plus).
by jahboater
Sat Jul 27, 2019 11:25 am
Forum: General discussion
Topic: Why is the RPi4 being advertised as a desktop computer?
Replies: 114
Views: 9751

Re: Why is the RPi4 being advertised as a desktop computer?

But, my experience over the last 3 weeks of using Pi4's as a light-use desktop replacement in a production environment (reasonable demand) is what it is... unpleasant and unreliable . To the chap that said it was my skills that were lacking... don't make me laugh, Sunshine. In the real world, where...
by jahboater
Sat Jul 27, 2019 11:14 am
Forum: General discussion
Topic: Learning Assembler on the Pi
Replies: 51
Views: 1519

Re: Learning Assembler on the Pi

1- The book is written specifically for the Pi 2 and 3, it would be safe to assume that a lot will work on the Pi 4, but not everything. What do you think might not work? The Pi2 (late model), Pi3, and Pi4 are all ARMv8 processors. At the "learning assembler" level you will not see any difference. ...
by jahboater
Sat Jul 27, 2019 10:47 am
Forum: Raspbian
Topic: Change raspbian looks, easy to do?
Replies: 6
Views: 305

Re: Change raspbian looks, easy to do?

How easy is it, to change the desktop looks of raspbian? I feel more comfortable with a windows-style task and start bar on the bottom. Is it easy to change the desktop to how Lubuntu 19.04 looks like? (SDDM) Or, if not, can I make it look like Mint, with a Cinnamon desktop, or Mate? Or worst case ...
by jahboater
Sat Jul 27, 2019 10:41 am
Forum: General discussion
Topic: Learning Assembler on the Pi
Replies: 51
Views: 1519

Re: Learning Assembler on the Pi

I suspect the 4 would work for most if not all, but but but there is still work going on to finish/finalize the software...also the ARM processor in the 4 is different so that might be an issue (I don't know the difference at the assembly level between them). Go with the Pi4 with Raspbian Buster Th...
by jahboater
Sat Jul 27, 2019 10:28 am
Forum: General discussion
Topic: Why is the RPi4 being advertised as a desktop computer?
Replies: 114
Views: 9751

Re: Why is the RPi4 being advertised as a desktop computer?

the daily volume of faults that require fixing. Either this is nonsense, or you have a faulty SD card, or your system management skills need improving. As Linux distros go I find Rasbian very reliable indeed. I have been using Linux professionally since its early days, and UNIX for years before tha...
by jahboater
Sat Jul 27, 2019 9:03 am
Forum: General discussion
Topic: Why is the RPi4 being advertised as a desktop computer?
Replies: 114
Views: 9751

Re: Why is the RPi4 being advertised as a desktop computer?

Heater wrote:
Sat Jul 27, 2019 8:50 am
Raspbian is perfectly fine.
And the 4GB Pi4 is a very decent platform to run it on.

Looks like I am having to go for a few weeks with just a Pi for a main computer (we are moving and all my big computers will be in storage). With the Pi4, lack of power is not something I am worried about.
by jahboater
Sat Jul 27, 2019 6:18 am
Forum: C/C++
Topic: StdLib Dirty Replacement Functions:
Replies: 20
Views: 748

Re: StdLib Dirty Replacement Functions:

I did not know that Intel C (which is what I had always known it as) supported the ARM host and targert. I don't think it does , though Intel did have xscale. I just mentioned it because it is a popular compiler. You have to pay for it, so I'll never use it! Oh I missed one, C18. Is C18 at least wo...
by jahboater
Fri Jul 26, 2019 6:38 pm
Forum: Python
Topic: The best way to shorten the code in several lines
Replies: 4
Views: 197

Re: The best way to shorten the code in several lines

Well spotted! I was going to suggest a LUT, but the simple arithmetic is obviously far better.
by jahboater
Fri Jul 26, 2019 6:13 pm
Forum: C/C++
Topic: StdLib Dirty Replacement Functions:
Replies: 20
Views: 748

Re: StdLib Dirty Replacement Functions:

While I agree very much if you are using only one of the big ones (did you mean to say LCC?, not heard of ICC), not so much when attempting to allow for any compiler. ICC is I ntel's C compiler which has always been highly regarded. I believe ICC and GCC work together in that they understand each o...
by jahboater
Fri Jul 26, 2019 5:54 pm
Forum: C/C++
Topic: StdLib Dirty Replacement Functions:
Replies: 20
Views: 748

Re: StdLib Dirty Replacement Functions:

Or different compilers may have different ways of accomplishing this making for different cases of what is best. It is headaches like that which keep me using Assembly language for many things. Though C is a good language, one of the most reasonable and easiest to use High Level Languages in my per...
by jahboater
Fri Jul 26, 2019 5:09 pm
Forum: C/C++
Topic: StdLib Dirty Replacement Functions:
Replies: 20
Views: 748

Re: StdLib Dirty Replacement Functions:

Thinking about your requirements - to avoid using the C library (quite reasonable for bare metal). The functions StrCpy8() and StrCpy12() will always be faster if they just use memcpy(). The compiler has knowledge that your functions cannot have:- - if the source argument is a literal StrCpy8( buf, ...

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