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by jcyr
Mon Jun 24, 2019 3:07 pm
Forum: General discussion
Topic: Raspberry Pi 4 Thread - general discussion
Replies: 221
Views: 8166

Re: Raspberry Pi 4 Thread - general discussion

EMMC really isn't a very good option IMO. Less reliable than SD cards over multiple writes and you cannot replace it when it fails, like you can with an SD card. SD also allows the possibility of keeping different software configs and solutions, per SD card. Oh, and as far as controlling costs, I'm...
by jcyr
Mon Jun 24, 2019 2:53 pm
Forum: General discussion
Topic: Raspberry Pi 4 Thread - general discussion
Replies: 221
Views: 8166

Re: Raspberry Pi 4 Thread - general discussion

I run RPs mostly headless and and care little about video enhancements. The gigabit Ethernet and BLuetooth enhancements will both be useful for my use cases. USB 3.0 might also be a huge plus for NAS builders. I wonder however about the I2C, SPI, PWM, and port logic blocks in the new SOC. Has backwa...
by jcyr
Fri May 31, 2019 9:13 pm
Forum: General discussion
Topic: RISC-V
Replies: 135
Views: 7976

Re: RISC-V

One of the canards that’s regularly trotted out in discussions of ARM vs. x86 processors is the idea that ARM chips are intrinsically more power efficient thanks to fundamental differences in the ISA. They aren't! They are more or less equal, on average, in terms of watts per compute unit. So in tha...
by jcyr
Fri May 31, 2019 4:26 pm
Forum: General discussion
Topic: RISC-V
Replies: 135
Views: 7976

Re: RISC-V

You can simply recompile to get round ISA differences. Only if you have the appropriate compiler and toolset. The whole point of an ISA is in part to allow the creation of said tools. A widely adopted standard ISA is more likely to have better tools. You cannot do that for the other stuff (generall...
by jcyr
Thu May 30, 2019 6:49 pm
Forum: General discussion
Topic: RISC-V
Replies: 135
Views: 7976

Re: RISC-V

RISC-V is just an ISA specification. It can be turned into silicon which can fulfil the roles from simple microcontroller, through SoC's, to full blown PC CPU's, and probably super computers as well with appropriate instruction set extensions. Not so sure about that later part! Is there a formal RI...
by jcyr
Wed May 29, 2019 12:19 am
Forum: General discussion
Topic: RISC-V
Replies: 135
Views: 7976

Re: RISC-V

If I get a real RISVC-V hardware I will be using Rust, Go or Free Pascal compilers, not C or C++. Huh! Serously!!! RUST has got to be the most awkward and counter intuitive mainstream language so far. Go belongs to Google and for me that's a show stopper. Pascal, well I used it many decades ago on ...
by jcyr
Wed Aug 08, 2018 8:54 pm
Forum: General discussion
Topic: (Old and now obsolete) REVIEW: X850 mSATA SSD storage expansion board
Replies: 112
Views: 50507

Re: REVIEW: X850 mSATA SSD storage expansion board

It may be, but I'm using a 5A brick so I don't think so. Also I run the Pi3 power through the proper micro USB connector instead of the IO pins. The odd thing is that all it takes is my removing the little USB interconnect PCB and all starts working normally. With the USB interconnect in place and b...
by jcyr
Wed Aug 08, 2018 1:30 pm
Forum: General discussion
Topic: (Old and now obsolete) REVIEW: X850 mSATA SSD storage expansion board
Replies: 112
Views: 50507

Re: REVIEW: X850 mSATA SSD storage expansion board

In addition to reboot problems, the X820 prevents Wifi from functioning correctly on my Pi3B and Pi3B+. Booting from SD, if I disconnect the USB to the SSD, wifi comes up fine. With USB connected, wlan0 is detected but refuses to come up.

Model X820 V1.3

Truly not impressed with this purchase!
by jcyr
Tue Aug 07, 2018 1:22 pm
Forum: Beginners
Topic: SupTronics x800 or X820 worth buying?
Replies: 9
Views: 4920

Re: SupTronics x800 or X820 worth buying?

I would not recommend the x820. Many reported incidents of failing reboots, which I'm experiencing first hand with the Pi3 B+.

Update: Also interferes with Wifi on RPi 3B and 3B+.
by jcyr
Thu Dec 28, 2017 1:49 am
Forum: Other projects
Topic: Aluminum enclosure for Raspberry Pi
Replies: 42
Views: 34882

Re: Aluminum enclosure for Raspberry Pi

In my network WiFi has to cover 3 stories and about 2800 sq. feet of floor space. I find it hard to believe that a metal case enclosing a chip antenna, with only a few small apertures, won't heavily attenuate the signal at most points of our 3D space. Only 1 to 4 db reduction... Sorry, that doesn't ...
by jcyr
Tue Dec 26, 2017 7:25 pm
Forum: General discussion
Topic: Can we get an 64bit OS?
Replies: 85
Views: 18532

Re: Can we get an 64bit OS?

As far as I know, no Bourne-style shell has ever tried to read an entire script into memory before executing.
Correct... as anyone who's tried modifying a bash script while it it running has found out.
by jcyr
Mon Dec 25, 2017 10:02 pm
Forum: General discussion
Topic: Can we get an 64bit OS?
Replies: 85
Views: 18532

Re: Can we get an 64bit OS?

Notebly I don't think you can do that in Windows.
+1 for Windows
by jcyr
Mon Dec 25, 2017 1:03 am
Forum: General discussion
Topic: Can we get an 64bit OS?
Replies: 85
Views: 18532

Re: Can we get an 64bit OS?

Thats why C uses "row major" addressing.
Only true for Western (left to right) cultures... ;)
by jcyr
Sun Dec 24, 2017 6:35 pm
Forum: General discussion
Topic: Can we get an 64bit OS?
Replies: 85
Views: 18532

Re: Can we get an 64bit OS?

There is a general trend to 64-bit processing that will eventually percolate to the ARM world. Already some well known 3rd party applications, such as pfSense, are planning X64 only. Sure, these are X86 based products, but they are targeted to small router configurations often less powerful than the...
by jcyr
Sat Dec 23, 2017 9:53 pm
Forum: General discussion
Topic: Can we get an 64bit OS?
Replies: 85
Views: 18532

Re: Can we get an 64bit OS?

But what if you want to map a 1TB file into RAM? Then you need a 64 bit OS. As far as I know... mmap() in C requires an offset parameter (offset into file) of type off_t which is 32 bits for 32 bit systems and 64 bits for 64 bit systems. So, I conclude if you want to memory map big files you need t...
by jcyr
Sat Dec 23, 2017 6:10 pm
Forum: General discussion
Topic: Can we get an 64bit OS?
Replies: 85
Views: 18532

Re: Can we get an 64bit OS?

Some databases use 64 bit offsets into files and memory map chunks of that as they work. I believe you are confusing 64-bit addressing with 64-bit integer support. All compilers and interpreters support 64 bit integers, even 32 bit versions. 64-bit file offsets have been supported for a long time n...
by jcyr
Sat Dec 23, 2017 3:42 pm
Forum: General discussion
Topic: Can we get an 64bit OS?
Replies: 85
Views: 18532

Re: Can we get an 64bit OS?

On a Linux system the virtual address split is at 0xc0000000. This gives you up to 3GB of addressable memory from user space. This space maps to 1GB of physical RAM, some of which is reserved for hardware use. If your application requires more than 3GB of data, it is indeed limited by the 32-bit imp...
by jcyr
Thu Dec 21, 2017 10:23 pm
Forum: Troubleshooting
Topic: Performance very bad after switching from SD to USB Boot
Replies: 5
Views: 1007

Re: Performance very bad after switching from SD to USB Boot

The USB stick is a Toshiba U364 USB 3.0 32GB TransMemory.
Don't know about that specific brand, but not all USB sticks are created equal. Performance varies based on size and cost. USB 3.0 doesn't buy you anything since the Pi's interfces are USB 2.0. You are subject to USB 2.0 tranfer rates.
by jcyr
Tue Dec 19, 2017 8:58 am
Forum: Off topic discussion
Topic: Net neutrality discussion
Replies: 17
Views: 4623

Re: Net neutrality discussion

Hmm... When I worked for Broadcom, I spent time in most of the locations you mention a well as Irvine, but never had cell connectivity issues! 60 dollars a month is crazy expensive by the way. You consider $60 a month for 2 phones with uncapped 4G data to be excessive! What would to call normal? Get...
by jcyr
Tue Dec 19, 2017 8:28 am
Forum: Off topic discussion
Topic: Future Networking features
Replies: 5
Views: 2924

Re: Future Networking features

If and when an SOC upgrade comes about I'd love to see it do away with the USB interface to Ethernet, and get an integrated GigE MAC/PHY with DMA capability. With such a controller there's no reason a Pi3 sized CPU couldn't handle GigE rates. But then, what would a single GigE port would buy you? No...
by jcyr
Tue Dec 19, 2017 4:13 am
Forum: Off topic discussion
Topic: Net neutrality discussion
Replies: 17
Views: 4623

Re: Net neutrality discussion

Cellular in the US has become more competitive than it was even 2 years ago! T-Mobile has done much the break the AT&T/Verizon quasi monopoly. They've forced competition by beating the incumbents on customer service, pricing, data services and contract free deals. John Legere is to cellular what Elo...
by jcyr
Mon Dec 18, 2017 9:39 pm
Forum: Gaming
Topic: Battery Options for handheld gaming device
Replies: 20
Views: 2627

Re: Battery Options for handheld gaming device

Why not a Pi0W. It has much lower power requirements and also includes WiFi and Bluetooth. Much less CPU capacity though, but for sigle threaded gaming it might work.
by jcyr
Mon Dec 18, 2017 7:43 pm
Forum: Gaming
Topic: Battery Options for handheld gaming device
Replies: 20
Views: 2627

Re: Battery Options for handheld gaming device

I've used Lipo. It is available and relatively safe technology provided you adhere to proper charging protocol. This probably means you'd rely on a commercially available charger rather than building your own. Lipo charging can be a delicate thing, where over charge/discharge can destroy the battery...
by jcyr
Mon Dec 18, 2017 3:18 pm
Forum: General programming discussion
Topic: VS17 Help
Replies: 34
Views: 13903

Re: VS17 Help

Real 3270s had wonderful keyboards and nice green letters on a black field. The first ones I used only did UPPER CASE text in 24 lines of 80 columns. Indeed. And that same keyboard later showed up with the first generation of IBM PCs. To this day those remain the gold standard in keyboard design. W...
by jcyr
Mon Dec 18, 2017 3:00 pm
Forum: Off topic discussion
Topic: Net neutrality discussion
Replies: 17
Views: 4623

Re: Net neutrality discussion

I wonder what the technical troubles would be with using extra-national sat-based internet from within US? Geostationary satellites are too distant to provide interactive Internet support. The quarter second lag time is too high. Thousands of specialized low orbit satellites might do the trick, but...

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