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Comment: Re:ARM64 is a mess (Score 1) 160

by NoNickNameForMe (#41837809) Attached to: ARM Announces 64-Bit Cortex-A50 Architecture

Oh, and there are 31 registers - X0 through X30. The 32nd register is special depending on the instruction - for ADD and SUB, "X31" means the stack pointer. For most other instructions, it means the zero register (reads as zero), something borrowed from MIPS, and allowing interesting register-only instruction forms to be used when the immediate value is zero. It does result in oddball uses though, like SUB SP, 0, X0 ; Set SP. to play with the stack pointer.

Hi, since you seem to be familiar with AArch64, perhaps you could explain why X31 == 0 is preferrable to X31 == FF's (all 1's). At least with FF's I can do an Increment or Decrement using 2's complement math, as well as bitwise testing for non-zero bits (though CLZ might suffice). With X31 == 0, the use case seems more limited (zero constant can be encoded pretty easily as an IMMEDIATE, and I presume that TEQ/CMP against 0 still exists)? PS. I'm familiar with ARM32, and somewhat familiar with MIPS-style fixed register constant usage.

Comment: Re:At what point does 'improvement' become a downs (Score 1) 96

by NoNickNameForMe (#40096275) Attached to: <em>Minecraft</em> Mod Adds Emulated 6502 Processor
Disclaimer: I've never played Minecraft

However, from the embedded video in this post, it felt like I'm in a 3D VLSI design tool. Maybe in the future we'll be literally designing devices one block at a time. Either that or the Nazcas have been playing Minecraft all this while....

Comment: What was old is new again (Score 1) 170

by NoNickNameForMe (#40048609) Attached to: Wozniak's Original System Description of the Apple ][

I ran into the problem of manipulating the 16 bit pointer data and its arithmetic in an 8 bit machine. My solution to this problem of handling 16 bit data, notably pointers, with an 8 bit microprocessor was to implement a nonexistent 16 bit processor in software, interpreter fashion

Linux on AVR ATMega

Comment: Re:Can Apples Wifi chipset work in adhoc mode? (Score 1) 461

by NoNickNameForMe (#31368936) Attached to: Apple Removes Wi-Fi Finders From App Store

i.e. Can an IPhone/ITouch app (even a Jailbroken one?) let you communicate with the other 50 IPhone /ITouch users in the train you're on, without paying the cell companies?

Wouldn't bluetooth be the better transport for this?

I don't believe Bluetooth can handle more than 8 devices in a single PAN.

Comment: Re:Can Apples Wifi chipset work in adhoc mode? (Score 1) 461

by NoNickNameForMe (#31368926) Attached to: Apple Removes Wi-Fi Finders From App Store
Yes and no. You can't create an ad hoc network on your iPhone, but you can join one. So if someone has a notebook and creates (seeds) and ad hoc wifi network, then you can connect to that ad hoc network (This issue has been raised in the iPhone Dev forum, and Apple is aware of it....for what it's worth).

Comment: Re:My understanding.... (Score 1) 171

by NoNickNameForMe (#30946838) Attached to: With New SDK, VoIP Over 3G Apps Now Working On iPhone

Basically, with a voice channel, the phone is just sending voice frames (we used to call this circuit switching). With VoIP, you'll have to tag each voice frame with a RTP+UDP+IP header, which ends up being larger than the actual voice data itself.

In addition, as you mentioned voice traffic has QoS enabled, while most Internet traffic runs as best effort.

So, in short, having VoIP over 3G is more of a geek's idea of cool rather than being of any real improvement to either voice quality or network efficiency, it's actually consuming more wireless bandwidth in the process (apart from cannibalizing the telco's revenue stream).

Comment: Re:Code in high-level (Score 1) 249

by NoNickNameForMe (#30775900) Attached to: Cliff Click's Crash Course In Modern Hardware

Hi, I agree with your sentiments (I've programmed in 8086 and 68HC11), though currently I'm trying to pick up ARM assembly language.

I find that 'gcc -Os' beats my handcrafted assembly due to the fact that the compiler can make a lot of 'short cut' optimizations based on what it know regarding memory address locations, etc. (via PC-relative indirect addressing) that would be difficult to take advantage of in Assembly without making it a non-maintainable hack.

I'm still trying to figure out how to beat gcc, but I don't think it'll be easy, especially not via micro-optimization where I take a C algorithm and reimplement it as given in Assembly.

Comment: Re:PasswordSafe (Score 1) 1007

by NoNickNameForMe (#30057924) Attached to: Best Tool For Remembering Passwords?
My only issue with text files encrypted with gpg is that one of these days, I'd accidentally type the gpg decryption key on the command line instead of when prompted, and the key will show up nicely in the shell history. After the "Arrgh!!" has subsided I'd have to remember to purge the history file, etc.

Comment: Re:Genuinely curious - TeXmacs? (Score 1) 674

by NoNickNameForMe (#28020679) Attached to: MS Word 2010 Takes On TeX

I've been slowly trying to pick up LyX to replace MS Word for writing papers and technical documents in Comp. Sci.

Currently the biggest impediment in using LyX is the graphics / diagram integration. There is no easy way to edit the diagram from LyX (unlike MS Word where diagrams are embedded); it is a multi-step process where I'd edit the diagram in some other program (Dia is still not polished enough yet), export to EPS, then relink to the EPS in LyX if the filename were different.

The other problem is that EPS output is pretty spotty in most MS programs. Visio's EPS output sucks, to put it mildly, and often cause postscript errors. SVG export is still not well supported in ANY tool I've tried.

I'd be interested to know what kind of apps and formats works best when dealing with diagrams which needs to be cross-platform (Linux & Mac OS X).

Comment: Re:Let me be the first to say: (Score 1) 341

by NoNickNameForMe (#27992731) Attached to: Office 2010 Technical Preview Leaked

I've never managed to get Word's autonumbering to work correctly in a continuously edited technical document despite many attempts to reset / modify the Heading X styles. The auto-formatting feature in MS Word is the worst culprit. This has always been MS Word's problem from the beginning (I'm currently using Office 2003 out of necessity).

I've never tried Office 2007, didn't want to invest any more energy on learning an incompatible interface on an application that does not deal well with technical documents.

LyX (LaTeX) is great for stuff like auto-numbering, but diagrams are a pain since there's no easy way to edit the diagram by double clicking on it, besides the lack of good diagramming tools that export to EPS format. Visio generates lousy EPS (deliberately?)

FrameMaker was the best of the lot. Unfortunately its market share and numerous bugs during the time Adobe bought it over meant that it's no longer a real contender for most people.

Human resources are human first, and resources second. -- J. Garbers