Raspberry Pi 3B+ Launches With Faster CPU, Dual-Band 802.11ac, Faster Ethernet

[caligula]

And that's not hampered by slow I/O? You'd have to go back to the days of DOS, to find PCs with such slow I/O performance!

Of course, that's when I learned programming, but I wasn't trying to do it on a modern 64-bit OS with corresponding bloat in the size of ... everything.

The original Raspberry Pi is comparable to a desktop Pentium 2 (around year 1997?) in terms of performance. Keep in mind the hard drives were quite slow back then and SD card has better random access latency. You can easily outperform RPis with Pentium 2 era PC using dual sockets and SCSI RAID5 disk arrays though.

[caligula]

The original intended use case for Raspberry Pi is providing a low-cost computer for learning programming. Besides education, the RPi foundation additionally seems to cater to HTPC users, and the maker community. Other use cases appear to be marginal at least to the foundation.

You probably assume that the learning apps need to run on the same system. They don't. Arduino is also designed for learning and people upload the apps from a real computer (or use firmata). Thos are two different paradigms, both for learning some programming.

Even 7 yo kids can program Arduino (e.g. my cousin did). IMHO running Scratch on RPi is a serious misuse of the hardware. ANY old computer could do that while ARMs typically don't excel at running desktop apps. ARM boards do all the other embedded tasks well. PCs, OTOH, were designed to run desktop apps but lack things like GPIO pin headers. Almost all machines since 1995 support VESA video modes and standard framebuffers. The machines can handle 100-1000 Mbps networks using ISA/PCI buses. No problems whatsoever. I'd argue that RPis aren't cheap either. The NOOB starter packs are pretty expensive compared to a plain board. The boards require fairly new monitors with HDMI when there's abundance of old DSUB/DVI monitors lying around. Same problem with old desktop computers. Besides, billions of smart phones are sold each year so why can't they study programming with a more capable ARM system in their very own phones?

[coder]

IMHO running Scratch on RPi is a serious misuse of the hardware. ANY old computer could do that

Pi is much lower power, and solid state. In developing countries, that counts for something.

Almost all machines since 1995 support VESA video modes and standard framebuffers. The machines can handle 100-1000 Mbps networks using ISA/PCI buses. No problems whatsoever.

1. VESA mode is usually hella painful.
2. ISA was sub-100 Mbps; PCI was sub-1000 Mbps.
3. HDDs don't last as long as most other PC components. So, you might have to spend some money replacing the HDD.
4. If you're using modern software, bloat means you'll need more RAM and you'll find load times are considerably longer than you recall.

The boards require fairly new monitors with HDMI when there's abundance of old DSUB/DVI monitors lying around.

DVI and HDMI are electrically identical. Both standards dictate a common subset of supported modes, meaning you can always drive a DVI monitor from your Pi's or any other HDMI port. But, I'd argue that HDMI-equipped TVs might be more plentiful than DVI-equipped monitors, at this point.

[chithanh]

And that's not hampered by slow I/O? You'd have to go back to the days of DOS, to find PCs with such slow I/O performance!

The RPi is maybe slow compared to other modern computers, but still plenty fast for its use case.

You probably assume that the learning apps need to run on the same system. They don't.

Any system that is not the family PC. Because kids and parents might be nervous that the experiments (installing Linux etc.) can break something. And this is explicitly the goal, letting kids explore everything without fear of consequences. Worst case, write a pristine image to the SD card and the Pi works again.

DVI and HDMI are electrically identical. Both standards dictate a common subset of supported modes, meaning you can always drive a DVI monitor from your Pi's or any other HDMI port. But, I'd argue that HDMI-equipped TVs might be more plentiful than DVI-equipped monitors, at this point.

That is true for the RPi but not in general. One common problem that affects mostly Allwinner chips is that HDMI mandates YUV support while DVI doesn't. So if your device only outputs YUV, then an RGB-only DVI monitor might not display anything.

[caligula]

The RPi is maybe slow compared to other modern computers, but still plenty fast for its use case.

Any system that is not the family PC. Because kids and parents might be nervous that the experiments (installing Linux etc.) can break something. And this is explicitly the goal, letting kids explore everything without fear of consequences. Worst case, write a pristine image to the SD card and the Pi works again.

You could achieve similar results with Live distros. Overlayfs or Btrfs snapshot based systems support easy rollbacks. Also you don't need to give root access to experiment with hardware these days. I've got USB powered GPIO/I2C dongles and they work just fine for non-root users. I'd argue that any single board computer is pretty bad for using desktop software as the hardware is so limited. You'll probably want USB keyboard, USB mouse, USB mass storage, USB dongles. You'll run out of connectors pretty quick. The onboard connector slots are too small for plugging two larger dongles next to each other. With all the extra USB hubs, keyboards, monitors etc. the price of the SBC becomes a tiny factor. You need $150 worth of equipment for a $35 board.

[caligula]

VESA mode is usually hella painful.

You can use drivers and toolkits such as SDL.

ISA was sub-100 Mbps; PCI was sub-1000 Mbps.

Wrong.

The last ISA (non-EISA) ports were 8 MHz & 16bits so 128 Mbps. That's > 100 Mbps. Keep in mind that those boards had controllers onboard for generating packets etc. The actual raw throughput towards the system bus is a lot less. Depending on payload size, the extra octets for ethernet frames comprise 2.5 to 48% of the packet size. In my book ISA can easily handle even 100 Mbps full duplex unless you do relay some heavily bidirectional traffic. Standard PCI (non PCI-X) bus is 66 MHz and 32 bits which equals to 2128 Mbps. Full duplex gigabit ethernet is 2x1000 Mbps minus ethernet frame stuff so 522 to 1950 Mbps between the CPU and the card. In fact, I have some Realtek 8169 based gigabit PCI ethernet cards lying around here.

[chithanh]

I think ISA did not have any standard speed initially, but later was fixed to 8.33 MHz.
Standard configuration of PCI was 32 MHz and 32 bits (well, 33 if you count parity).

[coder]

The RPi is maybe slow compared to other modern computers, but still plenty fast for its use case.

No. Kids will lose interest with something so slow and unresponsive. Back when computers were new and exotic, people were willing to wait for them. Now, they expect everything to be as responsive as smartphones.

That is true for the RPi but not in general. One common problem that affects mostly Allwinner chips is that HDMI mandates YUV support while DVI doesn't. So if your device only outputs YUV, then an RGB-only DVI monitor might not display anything.

Then they're non-conformant, because HDMI mandates 8-bit RGB support.

[coder]

You can use drivers and toolkits such as SDL.

To do what? What was your original point?

Wrong.

Wrong.

ISA and PCI were actual buses. So, the first point is that you're adding up the total pie, including overhead, that's shared by all devices. Your CPU is reading/writing your HDD over that same bus.

In fact, I have some Realtek 8169 based gigabit PCI ethernet cards lying around here.

Second point is that you never got 1 Gbps over that trash. Go ahead and try it. It'll never happen. Nobody ever got even 100 MBps over 33 MHz 32-bit PCI, which is the only flavor that was ever really mainstream.

But whether you get a full gigabit or only 600 Mbps isn't really the point. If you think these old PCs are so great, why aren't you using one? Go ahead and try it.

[chithanh]

No. Kids will lose interest with something so slow and unresponsive. Back when computers were new and exotic, people were willing to wait for them. Now, they expect everything to be as responsive as smartphones.

We were talking about I/O. The RPi is plenty fast when it comes to I/O.

Besides I/O, it is still sufficiently fast for learning programming. Raspbian comes with Geany preinstalled.

Then they're non-conformant, because HDMI mandates 8-bit RGB support.

I think you don't understand.

Quoting Wikipedia: "HDMI permits sRGB 4:4:4 chroma subsampling (8–16 bits per component), xvYCC 4:4:4 chroma subsampling (8–16 bits per component), YCbCr 4:4:4 chroma subsampling (8–16 bits per component), or YCbCr 4:2:2 chroma subsampling (8–12 bits per component)." DVI however only mandates that monitors accept RGB. This is why your claim that you can always drive DVI monitors from HDMI ports is false.