dfox

31 ms·

391.
by dfox 3y ago
The mentioned qc-usb driver seems to do some filtering. IIRC when I played with that 15-20 years ago qc-usb produced distinctly blurry images with slightly washed out colors, while the original windows driver produced images that are sharp,
392.
by dfox 3y ago
Unless the ethernet cable is made from copper clad steel, which is sometimes used for ethernet cables and very common for consumer grade phone and RF cables.
393.
by dfox 3y ago
The problem with typical OS-provided mutex is that it is almost always in some way distinctly non-cheap either because of the particular implementation or because of limitations imposed by ABI/API compatibility (and in some case both).
394.
by dfox 3y ago
The 160MFlOps of Cray-1 is the theoretical maximum of the implementation (as are the whatever FlOp/s numbers quoted by GPU vendors), while the numbers for Linux capable Broadcom SoCs in RaspberryPis are results from LINPACK. The Linpac
395.
by dfox 3y ago
That is kind of a niche use case ;) In the times when it was a real issue (I would hazard a guess that that means “before XP”) the reason was that the original registry on disk format made every registry access more or less O(n) in bunch of
396.
by dfox 3y ago
One of the things that I put some though into is that the PIO block is fast and you can build a custom fast interconnect from that (or maybe even Transputer Link) and then build a large distributed memory “supercomputer” from that. One of t
397.
by dfox 3y ago
I vaguely remember that Access.BUS (I2C based PC peripheral bus that was kind of a precursor to USB) did address assignment using somewhat similar protocol.
398.
by dfox 3y ago
I suspect that it is the other way around and the Finder and standard dialogs (both of which use slashes as path separator when you type the path) simply shows colons in filenames as slashes.
399.
by dfox 3y ago
Windows tries to keep a long term identity of all of the device instances that it knows about (and in the idela world assign the same COM port numer to the same physical serial adapter). For USB this is supposed to be done by combination of
400.
by dfox 4y ago
Implementing a CPU by writing an interpreter in lower level microcode is a obvious implementation strategy for CISC ISAs. But the mechanism how modern OoO x86 CPUs (and even many notionally RISC CPUs) works is different: The incoming instru
401.
by dfox 4y ago
Putting caps or even somewhat more complex networks in parralel to switches or around switches is a solution when you cannot change the rest of the system. Correct solution for this issue is debouncing logic (be it in HW or SW). But if for
402.
by dfox 4y ago
There is a no sane way to manufacture large enough decoupling capacitors in the semiconductor processess involved. Some ICs (including most of socketed CPUs) include some decoupling MLCCs in the module package, but still the bulk has to be
403.
by dfox 4y ago
For most of the embedded designs today the power planes are the bulk of low-ESR/ESL decoupling (even on 4 layer boards with powerplanes in the middle layers), it is a cap of ridiculously small capacity, but with essentially zero ESL&#x
404.
by dfox 4y ago
If you are driving something that really should not be a transmission line for your application from fast enough driver that makes it look like a transmission line then source termination (or just placing random resistor there as who the he
405.
by dfox 4y ago
Core ID in TSC_AUX is essentially an concession to userspace. As an OS and firmware you are supposed to identify CPU cores by means of their LAPIC ID (as read from APIC configurations MSR or from CPUID). Small issue there is that APIC IDs a
406.
by dfox 4y ago
There technically never was a “Tesla Inc.” with separate branches. There was a bunch of essentially unrelated companies named “Tesla something” that used the same brand and (obviously) traded with each other. There was similar pattern with
407.
by dfox 4y ago
These are just normal aluminium electrolytics. Usually these had outer plastic sheath (which makes the package look uninteresting), but they did not have to (AFAIK there were three separate ordering codes for sheath, no sheath and random, w
408.
by dfox 4y ago
The "-( 21 S 22 )-" thing is a speaker in the handset. The button is above that, labeled "VAR.". Probably the main reason why essentially the entire electronics is in the handset and why it is somewhat complex is that it
409.
by dfox 4y ago
The WNB prefix means that it is an custom application specific hybrid (as in "thick film on ceramic") module, that pretty much means that there never was any kind of documentation for the part. Obviously the function of the thing
410.
by dfox 4y ago
On AMD's amd64 platforms there is not much for the firmware to do in terms of the platform bring up as everything that is inside the CPU MCM gets initialized to some sane state (by a PSP-like additional management core, but AFAIK it is
411.
by dfox 4y ago
JVM was originally designed to run as a single thread because of bunch of factors that were relevant at that time: It was originally designed to run on embedded-ish platforms without any real OS. And in such an environment it makes perfect
412.
by dfox 4y ago
This is relevant to environments where the user code is statically compiled into native code that depends on some thin runtime library and more or less directly interacts with C code. In case of full blown VM many of these problems are not
413.
by dfox 4y ago
Smoke(/fire in general) alarms are not a good example of a thing with high specificity. You perceive it that way, but what you see is the result of somebody getting paged about it and then checking (preferably physically, but also thro
414.
by dfox 4y ago
One of the ideas behind HTML5 is that while there is some concept of validity and well-formedness, essentially any random stream bytes describes exactly one DOM tree, in some cases the resulting tree is surprising, but even then should be s
415.
by dfox 4y ago
For me the main thing that detracts from the content is that the images you use are often irrelevant to what you are saying which makes the format feel like a straight-forward way how to make video out of what should be a blog post. Two exa
416.
by dfox 4y ago
The point is that you do not want to do any kind of heap cleanup before exit. The intention isn't to zero the pages, but to outright discard all of them (which is going to be done by the kernel anyway).
417.
by dfox 4y ago
That is the worst case if the process had leaked that part of the heap, but it is an optimal case on process exit. On OS with any kind of process isolation walking over most of the heap before exiting as to "correctly free it" is
418.
by dfox 4y ago
It was not that much of an engineering decision as a simple requirement for the chip to be feasible. At that time 40pin DIL was effectively the largest package that could be made at production scale.
419.
by dfox 4y ago
That depends on exactly what kind of DBMS and underlying OS one is talking about. For DBMS that runs as one daemon or set of related daemons that has some kind of mechanism to share the afore mentioned buffer pool and synchronize acces to i
420.
by dfox 4y ago
malloc(3) does not know or care about whether the OS actually commits the VM allocation that it got from somewhere (be it mmap(2) or sbrk(2)), apart from the fact that most implementations of malloc would write some kind of book-keeping hea

More ›