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http://www.ebuyer.com/708786-recreated-zx-spectrum-kyb-zxspectrumbt
1. Why would anybody want this?
2. THE PRICE!!
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On Mon, 26 Oct 2015 18:12:33 +0000, Orchid Win7 v1 wrote:
> http://www.ebuyer.com/708786-recreated-zx-spectrum-kyb-zxspectrumbt
>
> 1. Why would anybody want this?
Nostalga.
Or as a teaching tool - earlier computer systems were far less complex
than modern ones, so starting a student off with a simpler system can
make learning much easier, depending on the goals of the instruction.
Jim
--
"I learned long ago, never to wrestle with a pig. You get dirty, and
besides, the pig likes it." - George Bernard Shaw
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-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256
Le 26/10/2015 19:12, Orchid Win7 v1 a écrit :
> http://www.ebuyer.com/708786-recreated-zx-spectrum-kyb-zxspectrumbt
>
> 1. Why would anybody want this?
>
> 2. THE PRICE!!
Isn't there a violation of design ? Would Amstrad not sue ?
(IIRC, Amstrad bought the rom of spectrum, which include the basic,
and might have let them in public domain, at least for emulator, yet
the design is part of the IP of Sinclair that also went into Amstrad's
hands).
The interesting part of the spectrum was the video output (PAL), the
expansion bus, and the tape facility. So far, all of them are missing
from the recreation.
How do you display ? (Pal is dead, and there is no display connector)
How do you print ?
How do you save & load ?
and IIRC, the keyboard (on membrane/printed circuit) was the weakest
point of the sinclair (with age, they become brittle and break when
you open the machine). That, and with usage, the gum of the keyboard
loose the print on it if you clean it too hard.
Back to the recreation: it's only a keyboard, you need a real
bluetooth device with a display... and you cannot even connect the old
joystick to it either.
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On 26/10/2015 06:27 PM, Jim Henderson wrote:
> On Mon, 26 Oct 2015 18:12:33 +0000, Orchid Win7 v1 wrote:
>> 1. Why would anybody want this?
>
> Nostalga.
OK, I get nostalga. I am currently sitting next to an Amiga 1200. But at
this price?! Jesus, you could surely buy a *real* Spectrum for less money!
(Now I'm curious to know what the original retail price was...)
> Or as a teaching tool - earlier computer systems were far less complex
> than modern ones, so starting a student off with a simpler system can
> make learning much easier, depending on the goals of the instruction.
Isn't that what the Raspberry Pi was supposed to do?
Don't get me wrong, I think it's *way* easier to learn system-level
programming on obsolete hardware. (It's how *I* did it!) But I doubt
many kids these days would get out of bed to see some blocky 8-bit graphics.
Which is why they invented the Pi, with it's full-HD video and audio
capabilities and 3D rendering support... Which thus makes it impossible
to do system-level programming, kinda negating the point.
And besides, for £0 you can probably just *download* a Spectrum emulator
onto your PC or indeed phone or tablet... You don't actually need a
physical box. (I don't know, but I'd be surprised if this thing actually
contains a Z80. I bet it's really just a smartphone SoC running an
emulator!)
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On 26/10/2015 06:46 PM, Le_Forgeron wrote:
> Isn't there a violation of design ? Would Amstrad not sue ?
Surely they bought the rights to do this. Otherwise there's a wide range
of trademark and copyright violations. Some rip-off company in China
might do that, but a commercial product like this is almost surely licensed.
> The interesting part of the spectrum was the video output (PAL), the
> expansion bus, and the tape facility. So far, all of them are missing
> from the recreation.
But it has Wi-Fi!
(Seriously, what the heck is that for?)
> How do you display ? (Pal is dead, and there is no display connector)
I might be wrong, but the "5V DC" connector looks *suspiciously* like an
HDMI port. (Or maybe it's micro-USB?)
> How do you print ?
>
> How do you save& load ?
WiFi, I guess?
(Wait, you can *print* from a Spectrum? I never knew that!)
> and IIRC, the keyboard (on membrane/printed circuit) was the weakest
> point of the sinclair (with age, they become brittle and break when
> you open the machine). That, and with usage, the gum of the keyboard
> loose the print on it if you clean it too hard.
I don't know, I quite liked that keyboard, and the little click noise it
used to make when you type stuff...
...wait, scrub that. I just remembered what it was like to *type*
anything! But still, it's arguably the single most memorable feature.
> Back to the recreation: it's only a keyboard, you need a real
> bluetooth device with a display... and you cannot even connect the old
> joystick to it either.
Oh, really? Wow, that's poor. Especially at such a price... You could
find a *real* one for less on ebay or whatever.
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-----BEGIN PGP SIGNED MESSAGE-----
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Le 26/10/2015 20:05, Orchid Win7 v1 a écrit :
>
> (Wait, you can *print* from a Spectrum? I never knew that!)
Yes, there was a thermal printer (for thermal paper) to connect on the
expansion bus.
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On 26/10/2015 07:19 PM, Le_Forgeron wrote:
> Le 26/10/2015 20:05, Orchid Win7 v1 a écrit :
>> (Wait, you can *print* from a Spectrum? I never knew that!)
>
> Yes, there was a thermal printer (for thermal paper) to connect on the
> expansion bus.
Huh. I did not know that. Come to mention it, I don't remember there
being an expansion port!
Ah, the hours I wasted with our Spectrum hooked up to a portable 4" CRT
monitor. Do you know what 8x8 characters look like on a 4" screen with
manually-tuned RF? I do...
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Le 26/10/2015 20:24, Orchid Win7 v1 a écrit :
> On 26/10/2015 07:19 PM, Le_Forgeron wrote:
>> Le 26/10/2015 20:05, Orchid Win7 v1 a écrit :
>>> (Wait, you can *print* from a Spectrum? I never knew that!)
>>
>> Yes, there was a thermal printer (for thermal paper) to connect
>> on the expansion bus.
>
> Huh. I did not know that. Come to mention it, I don't remember
> there being an expansion port!
You remember the pcb at the back, that is the expansion bus... At
least for the original 16k and 48k model. I do not remember if there
was a default plug/cache on it or if it was all time open.
The 128k wasted all: the keyboard and rear was different. (and the
128k were via bank switching of 16k... otherwise, it was like a 32k +
16k switched... and the double size rom (16k x 2) was also switched.
Well, it's only a 16 bits Z80, what did you expect !
>
> Ah, the hours I wasted with our Spectrum hooked up to a portable 4"
> CRT monitor. Do you know what 8x8 characters look like on a 4"
> screen with manually-tuned RF? I do...
Mine was hooked on TV. oh the battles vs the TV shows.
Only 2 colours per 8x8 pixels was the main drawback of the display.
(and the fancy flash mode bit... hardly documented, surprising to use)
That, and only 8 colours.
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On 10/26/2015 9:06 PM, Le_Forgeron wrote:
> That, and only 8 colours.
Colours! and eight of them?
The first games I played the output was a printer.
--
Regards
Stephen
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On Mon, 26 Oct 2015 19:01:28 +0000, Orchid Win7 v1 wrote:
> On 26/10/2015 06:27 PM, Jim Henderson wrote:
>> On Mon, 26 Oct 2015 18:12:33 +0000, Orchid Win7 v1 wrote:
>>> 1. Why would anybody want this?
>>
>> Nostalga.
>
> OK, I get nostalga. I am currently sitting next to an Amiga 1200. But at
> this price?! Jesus, you could surely buy a *real* Spectrum for less
> money!
>
> (Now I'm curious to know what the original retail price was...)
https://en.wikipedia.org/wiki/ZX_Spectrum
Lists some original retail price. Don't thank me, thank Google. ;)
>> Or as a teaching tool - earlier computer systems were far less complex
>> than modern ones, so starting a student off with a simpler system can
>> make learning much easier, depending on the goals of the instruction.
>
> Isn't that what the Raspberry Pi was supposed to do?
Depends a lot on what you want to teach.
> Don't get me wrong, I think it's *way* easier to learn system-level
> programming on obsolete hardware. (It's how *I* did it!) But I doubt
> many kids these days would get out of bed to see some blocky 8-bit
> graphics.
Also depends on what you want to teach.
> Which is why they invented the Pi, with it's full-HD video and audio
> capabilities and 3D rendering support... Which thus makes it impossible
> to do system-level programming, kinda negating the point.
You certainly can do system-level programming on the RPi. How do you
think you get a kernel developed to run on it? ;)
> And besides, for £0 you can probably just *download* a Spectrum emulator
> onto your PC or indeed phone or tablet... You don't actually need a
> physical box. (I don't know, but I'd be surprised if this thing actually
> contains a Z80. I bet it's really just a smartphone SoC running an
> emulator!)
Not the same, and as I said, it depends on what you want to teach.
Jim
--
"I learned long ago, never to wrestle with a pig. You get dirty, and
besides, the pig likes it." - George Bernard Shaw
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>> (Now I'm curious to know what the original retail price was...)
>
> https://en.wikipedia.org/wiki/ZX_Spectrum
>
> Lists some original retail price. Don't thank me, thank Google. ;)
Hmm. So, at £99, this recreation is *almost* the same price as the
original, 30+ years later. Nice.
>> Isn't that what the Raspberry Pi was supposed to do?
>
> Depends a lot on what you want to teach.
I guess the Pi by itself doesn't do a lot; it's great for building crazy
robots, if *electronics* is what you're trying to teach. But you need
more components to make a usable computer out of it. And then there's so
many other bits plugged in, you lose sight of the fact that the little
circuit board in the middle is the part that's actually "doing" stuff.
>> Don't get me wrong, I think it's *way* easier to learn system-level
>> programming on obsolete hardware. (It's how *I* did it!) But I doubt
>> many kids these days would get out of bed to see some blocky 8-bit
>> graphics.
>
> Also depends on what you want to teach.
When I was a kid, 8-bit graphics were all you could ask for. I can
actually recall spending *multiple hours* playing Space Invaders. I
can't imagine why; today it seems like the most boring game imaginable!
It wouldn't hold my attention for ten seconds. And that's kinda my
point; kids these days have smartphones in their pockets. Why would they
bother with this obsolete thing? (Unless you manage to convince them
that its arcane-ness makes it "special" rather than just dumb.)
>> Which is why they invented the Pi, with it's full-HD video and audio
>> capabilities and 3D rendering support... Which thus makes it impossible
>> to do system-level programming, kinda negating the point.
>
> You certainly can do system-level programming on the RPi. How do you
> think you get a kernel developed to run on it? ;)
You're aware that to this day, the OS includes a closed-source binary
blob that only people who sign an NDA are allowed to look inside, right?
Literally, you cannot operate the GPU without signing an NDA or using
closed-source code. And since this is a mobile phone SoC, the GPU
controls the CPU, not the other way around...
But sure, once you've started the CPU, you can do system-level
programming. Good luck getting anything interesting done; it's not like
you can just poke 53280 to change the overscan colour... ;-)
>> And besides, for £0 you can probably just *download* a Spectrum emulator
>> onto your PC or indeed phone or tablet... You don't actually need a
>> physical box.
>
> Not the same, and as I said, it depends on what you want to teach.
I will admit, particularly for a younger audience, there's a certain
something to having it be a hardware box.
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>> Huh. I did not know that. Come to mention it, I don't remember
>> there being an expansion port!
>
> You remember the pcb at the back, that is the expansion bus... At
> least for the original 16k and 48k model. I do not remember if there
> was a default plug/cache on it or if it was all time open.
Huh. I forgot about that. Yeah, I think we had the 16K model. Not 100%
sure...
> The 128k wasted all: the keyboard and rear was different. (and the
> 128k were via bank switching of 16k... otherwise, it was like a 32k +
> 16k switched... and the double size rom (16k x 2) was also switched.
> Well, it's only a 16 bits Z80, what did you expect !
So there *was* a system with bank-switching! I'm so glad I invented that
idea when I was only 11 years old... I *knew* somebody must have thought
of it before!
>> Ah, the hours I wasted with our Spectrum hooked up to a portable 4"
>> CRT monitor. Do you know what 8x8 characters look like on a 4"
>> screen with manually-tuned RF? I do...
>
> Mine was hooked on TV. oh the battles vs the TV shows.
> Only 2 colours per 8x8 pixels was the main drawback of the display.
> (and the fancy flash mode bit... hardly documented, surprising to use)
> That, and only 8 colours.
Oh yeah, this was a TV too. A portable TV for camping. Which, if you
know anything about CRT, "portable" doesn't really come into it. The TV
was 4" at the front, but about 9" long to accommodate the huge tube and
transformer at the back. Bloody heavy too! And with manual tuning, for
some reason... I'm guessing it was cheap?
For those that don't know, mis-tuned RF signals result in a weird kind
of zig-zag ghosting pattern that's very distracting...
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On 26/10/2015 09:06 PM, Le_Forgeron wrote:
> Only 2 colours per 8x8 pixels was the main drawback of the display.
Oh yeah... I forgot about that! One time I wrote a program to draw
randomly positioned circles in random colours. After a few minutes of
drawing, most of the pixels were in the "on" state, but there were weird
squares of colour that changed every time a new circle was started.
I also remember saving several test patterns to tape, and eventually
discovering which colour provoked which tone from the speaker... Jesus,
I was bored as a child!
I've always wanted to know... why is the framebuffer arranged so
weirdly? Like, as you load a picture file, rather than filling from top
to bottom, it seems to fill every Nth line...
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On Mon, 26 Oct 2015 22:38:03 +0000, Orchid Win7 v1 wrote:
>> Depends a lot on what you want to teach.
>
> I guess the Pi by itself doesn't do a lot; it's great for building crazy
> robots, if *electronics* is what you're trying to teach. But you need
> more components to make a usable computer out of it. And then there's so
> many other bits plugged in, you lose sight of the fact that the little
> circuit board in the middle is the part that's actually "doing" stuff.
I've got OpenELEC running on one; it makes a reasonable media server.
Nothing else really plugged in, either. HDMI, external hard drive,
power. Wireless keyboard/mouse combo that I generally don't use.
>>> Don't get me wrong, I think it's *way* easier to learn system-level
>>> programming on obsolete hardware. (It's how *I* did it!) But I doubt
>>> many kids these days would get out of bed to see some blocky 8-bit
>>> graphics.
>>
>> Also depends on what you want to teach.
>
> When I was a kid, 8-bit graphics were all you could ask for. I can
> actually recall spending *multiple hours* playing Space Invaders. I
> can't imagine why; today it seems like the most boring game imaginable!
> It wouldn't hold my attention for ten seconds. And that's kinda my
> point; kids these days have smartphones in their pockets. Why would they
> bother with this obsolete thing? (Unless you manage to convince them
> that its arcane-ness makes it "special" rather than just dumb.)
Lower end equipment can help kids and students understand where the
technology comes from and how it developed over time. Understanding the
past is useful to seeing ways in which things can be done in the future.
>>> Which is why they invented the Pi, with it's full-HD video and audio
>>> capabilities and 3D rendering support... Which thus makes it
>>> impossible to do system-level programming, kinda negating the point.
>>
>> You certainly can do system-level programming on the RPi. How do you
>> think you get a kernel developed to run on it? ;)
>
> You're aware that to this day, the OS includes a closed-source binary
> blob that only people who sign an NDA are allowed to look inside, right?
> Literally, you cannot operate the GPU without signing an NDA or using
> closed-source code. And since this is a mobile phone SoC, the GPU
> controls the CPU, not the other way around...
Yes, but that's true on a lot of PCs that run Linux as well. That
doesn't mean you can't do system-level programming on it.
> But sure, once you've started the CPU, you can do system-level
> programming. Good luck getting anything interesting done; it's not like
> you can just poke 53280 to change the overscan colour... ;-)
I think there's a lot you can do that's interesting without any video at
all.
>>> And besides, for £0 you can probably just *download* a Spectrum
>>> emulator onto your PC or indeed phone or tablet... You don't actually
>>> need a physical box.
>>
>> Not the same, and as I said, it depends on what you want to teach.
>
> I will admit, particularly for a younger audience, there's a certain
> something to having it be a hardware box.
Absolutely.
Jim
--
"I learned long ago, never to wrestle with a pig. You get dirty, and
besides, the pig likes it." - George Bernard Shaw
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Le 26/10/2015 23:43, Orchid Win7 v1 a écrit :
> I've always wanted to know... why is the framebuffer arranged so
> weirdly? Like, as you load a picture file, rather than filling from top
> to bottom, it seems to fill every Nth line...
Probably because Pal is an interleaved image: there is odd and even
frames. It was probably easier for the electronic in charge of
generating the lines in that order instead of obvious linear order.
IIRC the memory was not a dual access memory (that's expensive), so for
the chip to generate the signal, it might have been easier to read
consecutive address (an hardware counter is cheap).
Oh, it was a time in which accessing memory was easy: presents an
address on the address bus, read the data on the data bus. No column &
no row selection, no wasted cycles to wait for the data (no CAS Latency !)
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On 27/10/2015 07:23 AM, Le_Forgeron wrote:
> Le 26/10/2015 23:43, Orchid Win7 v1 a écrit :
>> I've always wanted to know... why is the framebuffer arranged so
>> weirdly? Like, as you load a picture file, rather than filling from top
>> to bottom, it seems to fill every Nth line...
>
> Probably because Pal is an interleaved image: there is odd and even
> frames. It was probably easier for the electronic in charge of
> generating the lines in that order instead of obvious linear order.
>
> IIRC the memory was not a dual access memory (that's expensive), so for
> the chip to generate the signal, it might have been easier to read
> consecutive address (an hardware counter is cheap).
See, for example, this image:
https://i.ytimg.com/vi/O6uwfM8F5uU/hqdefault.jpg
It seems to load every 8th line, for the top 6 groups, and then load
every 8th line for the next 6 groups, and so on... That's a really weird
order. I could understand if it was loading all the odd lines and then
all the even lines, but it's much more complicated than that.
(Also, recall that the Spectrum doesn't go to high enough resolutions
for the odd/even scans to make sense; every pixel is at least two
scanlines high!)
> Oh, it was a time in which accessing memory was easy: presents an
> address on the address bus, read the data on the data bus. No column &
> no row selection, no wasted cycles to wait for the data (no CAS Latency !)
I was shocked an horrified when I realised that RAM doesn't work this
way any more. It seems today, the difference between DDR3-1333 and
DDR3-1600 is merely the speed of the complex bus protocol connecting the
processor chip to the RAM chips; the actual memory cells themselves are
exactly the same speed. It's like the difference between a USB2 HD and a
USB3 HD; it's the same physical harddisk in there, just connected to a
faster bus. But it won't access your files any quicker!
But then, I remember being horrified when I realise that even since
waaaay back in the 80386, the processor isn't actually *executing* your
instructions any more. It's compiling them into an intermediate RISC
language and doing dependency analysis and branch prediction and cache
management and... man, just EXECUTE THE CODE ALREADY! Sheesh...
The problem with x86, of course, is the forty years of backwards
compatibility. :-P
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Am 26.10.2015 um 19:12 schrieb Orchid Win7 v1:
> http://www.ebuyer.com/708786-recreated-zx-spectrum-kyb-zxspectrumbt
>
> 1. Why would anybody want this?
Because their original has worn out?
> 2. THE PRICE!!
Yeah, especially once you factor in inflation. We really should have had
the price back then!
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Am 27.10.2015 um 09:29 schrieb Orchid Win7 v1:
> On 27/10/2015 07:23 AM, Le_Forgeron wrote:
>> Le 26/10/2015 23:43, Orchid Win7 v1 a écrit :
>>> I've always wanted to know... why is the framebuffer arranged so
>>> weirdly? Like, as you load a picture file, rather than filling from top
>>> to bottom, it seems to fill every Nth line...
>>
>> Probably because Pal is an interleaved image: there is odd and even
>> frames. It was probably easier for the electronic in charge of
>> generating the lines in that order instead of obvious linear order.
>>
>> IIRC the memory was not a dual access memory (that's expensive), so for
>> the chip to generate the signal, it might have been easier to read
>> consecutive address (an hardware counter is cheap).
>
> See, for example, this image:
>
> https://i.ytimg.com/vi/O6uwfM8F5uU/hqdefault.jpg
>
> It seems to load every 8th line, for the top 6 groups, and then load
> every 8th line for the next 6 groups, and so on... That's a really weird
> order. I could understand if it was loading all the odd lines and then
> all the even lines, but it's much more complicated than that.
Actually judging from the image that seems to be 8 groups, not 6.
The Amstrad CPC had a similar frame buffer arrangement, though a little
simpler.
In the case of the Amstrad CPC, this was easily explained:
The CRT controllers used back in those days were originally designed for
text-only display, such as in text terminals: In sync with the cathode
ray, the CRTC would generate an address into a text buffer, plus a
separate pixel row address; in normal operation, the former would be
used to fetch a character code from the text framebuffer; the character
code combined with the pixel row address would then be used as an index
into a character ROM, to fetch the bit pattern of a single pixel row of
the character in question. The CRTC would then fetch that bit pattern
into a shift register, to control the cathode ray brightness for
(typically) 8 pixels.
Such controller chips were already widely available back then, while
dedicated graphics CRTCs were not.
To use such a text CRTC for graphics display with a minimum of
circuitry, a clean framebuffer layout would have required to make the
image width a power of 2; in that case you could splice the text buffer
address into a lower and higher portion (being equivalent to a column
and super-row address, respectively), and insert the pixel row address
between the two (as the row address) to generate a framebuffer address.
But with any non-power of 2 image width, this scheme would either
utterly break down, or require you to sacrifice precious memory.
Therefore, typically the text buffer address would simply be used as the
lower portion of the framebuffer address, and the pixel row address
would be used as the higher portion, resulting in the 8-line interleave
pattern.
In the case of the ZX Spectrum, the framebuffer layout is less easily
explained: First of all, it doesn't seem to use a dedicated CRTC, but
has this functionality integrated into a custom chip - which sounds like
an expensive solution to me. But I guess it is safe to assume that the
custom chip wasn't designed from scratch, but just combined
miscellaneous 3rd party integrated circuitry on a single chunk of
silicon, so in a sense it may have had a text CRTC after all.
However, the display width is 256 pixels, so it would have been easy to
splice the text buffer address as explained above, and thus get a simple
frame buffer layout.
One potential reason could be that the framebuffer address
double-featured as a dynamic refresh address for the DRAM cells. Or the
designer was so preoccupied with this way of doing it that he didn't
realize it could be done easier. Or he wanted to keep the design
flexible to support different screen resolutions.
This still doesn't explain the additional grouping of the image into
bocks of 64 pixel rows. I must confess I have no idea why anyone would
want to do that, unless it's /some/ artifact of the CRTC used.
> I was shocked an horrified when I realised that RAM doesn't work this
> way any more. It seems today, the difference between DDR3-1333 and
> DDR3-1600 is merely the speed of the complex bus protocol connecting the
> processor chip to the RAM chips; the actual memory cells themselves are
> exactly the same speed. It's like the difference between a USB2 HD and a
> USB3 HD; it's the same physical harddisk in there, just connected to a
> faster bus. But it won't access your files any quicker!
It does help with bulk memory access though.
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Le 2015-10-27 03:23, Le_Forgeron a écrit :
> Le 26/10/2015 23:43, Orchid Win7 v1 a écrit :
>> I've always wanted to know... why is the framebuffer arranged so
>> weirdly? Like, as you load a picture file, rather than filling from top
>> to bottom, it seems to fill every Nth line...
>
> Probably because Pal is an interleaved image: there is odd and even
> frames. It was probably easier for the electronic in charge of
> generating the lines in that order instead of obvious linear order.
It's because the phosphorescent particles on the CRT face would dim too
much by the time the scanning electron beam came back to tickle them
back to life. By having an interleaved image, the flicker was less
apparent.
--
/*Francois Labreque*/#local a=x+y;#local b=x+a;#local c=a+b;#macro P(F//
/* flabreque */L)polygon{5,F,F+z,L+z,L,F pigment{rgb 9}}#end union
/* @ */{P(0,a)P(a,b)P(b,c)P(2*a,2*b)P(2*b,b+c)P(b+c,<2,3>)
/* gmail.com */}camera{orthographic location<6,1.25,-6>look_at a }
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On 27/10/2015 01:56 PM, Francois Labreque wrote:
> Le 2015-10-27 03:23, Le_Forgeron a écrit :
>> Probably because Pal is an interleaved image: there is odd and even
>> frames. It was probably easier for the electronic in charge of
>> generating the lines in that order instead of obvious linear order.
>
> It's because the phosphorescent particles on the CRT face would dim too
> much by the time the scanning electron beam came back to tickle them
> back to life. By having an interleaved image, the flicker was less
> apparent.
I have personally used an ancient Grundig CRT TV with an Amiga 1200 set
to a high enough resolution that pixels are 1 scanline high.
The flicker is *crazy*!
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On 27/10/2015 11:28 AM, clipka wrote:
> Am 27.10.2015 um 09:29 schrieb Orchid Win7 v1:
>> See, for example, this image:
>>
>> https://i.ytimg.com/vi/O6uwfM8F5uU/hqdefault.jpg
>>
>> It seems to load every 8th line, for the top 6 groups, and then load
>> every 8th line for the next 6 groups, and so on... That's a really weird
>> order. I could understand if it was loading all the odd lines and then
>> all the even lines, but it's much more complicated than that.
>
> Actually judging from the image that seems to be 8 groups, not 6.
Yeah, I can't count.
> The Amstrad CPC had a similar frame buffer arrangement, though a little
> simpler.
>
> In the case of the Amstrad CPC, this was easily explained:
>
> The CRT controllers used back in those days were originally designed for
> text-only display, such as in text terminals: In sync with the cathode
> ray, the CRTC would generate an address into a text buffer, plus a
> separate pixel row address; in normal operation, the former would be
> used to fetch a character code from the text framebuffer; the character
> code combined with the pixel row address would then be used as an index
> into a character ROM, to fetch the bit pattern of a single pixel row of
> the character in question. The CRTC would then fetch that bit pattern
> into a shift register, to control the cathode ray brightness for
> (typically) 8 pixels.
>
> Such controller chips were already widely available back then, while
> dedicated graphics CRTCs were not.
>
> To use such a text CRTC for graphics display with a minimum of
> circuitry, a clean framebuffer layout would have required to make the
> image width a power of 2; in that case you could splice the text buffer
> address into a lower and higher portion (being equivalent to a column
> and super-row address, respectively), and insert the pixel row address
> between the two (as the row address) to generate a framebuffer address.
> But with any non-power of 2 image width, this scheme would either
> utterly break down, or require you to sacrifice precious memory.
>
> Therefore, typically the text buffer address would simply be used as the
> lower portion of the framebuffer address, and the pixel row address
> would be used as the higher portion, resulting in the 8-line interleave
> pattern.
>
>
> In the case of the ZX Spectrum, the framebuffer layout is less easily
> explained: First of all, it doesn't seem to use a dedicated CRTC, but
> has this functionality integrated into a custom chip - which sounds like
> an expensive solution to me. But I guess it is safe to assume that the
> custom chip wasn't designed from scratch, but just combined
> miscellaneous 3rd party integrated circuitry on a single chunk of
> silicon, so in a sense it may have had a text CRTC after all.
>
> However, the display width is 256 pixels, so it would have been easy to
> splice the text buffer address as explained above, and thus get a simple
> frame buffer layout.
>
> One potential reason could be that the framebuffer address
> double-featured as a dynamic refresh address for the DRAM cells. Or the
> designer was so preoccupied with this way of doing it that he didn't
> realize it could be done easier. Or he wanted to keep the design
> flexible to support different screen resolutions.
>
> This still doesn't explain the additional grouping of the image into
> bocks of 64 pixel rows. I must confess I have no idea why anyone would
> want to do that, unless it's /some/ artifact of the CRTC used.
That... is some interesting theorising, actually! Makes the most sense
out of anything I've heard.
>> I was shocked an horrified when I realised that RAM doesn't work this
>> way any more.
>
> It does help with bulk memory access though.
Only if your RAM bus is drastically slower than everything else in the
system...
I always wondered why nobody puts, say, 1GB of RAM onto the same die as
the CPU, so bus speed becomes a total non-issue. And then I read the
specs of the Raspberry Pi and thought "OK, NM..."
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On 26/10/2015 11:31 PM, Jim Henderson wrote:
> On Mon, 26 Oct 2015 22:38:03 +0000, Orchid Win7 v1 wrote:
>> I guess the Pi by itself doesn't do a lot; it's great for building crazy
>> robots, if *electronics* is what you're trying to teach. But you need
>> more components to make a usable computer out of it. And then there's so
>> many other bits plugged in, you lose sight of the fact that the little
>> circuit board in the middle is the part that's actually "doing" stuff.
>
> I've got OpenELEC running on one; it makes a reasonable media server.
>
> Nothing else really plugged in, either. HDMI, external hard drive,
> power. Wireless keyboard/mouse combo that I generally don't use.
At that point, doesn't it kinda make it look like *the screen* is all
the smarts? Not the inconspicuous little box in the corner?
>> It wouldn't hold my attention for ten seconds. And that's kinda my
>> point; kids these days have smartphones in their pockets. Why would they
>> bother with this obsolete thing? (Unless you manage to convince them
>> that its arcane-ness makes it "special" rather than just dumb.)
>
> Lower end equipment can help kids and students understand where the
> technology comes from and how it developed over time. Understanding the
> past is useful to seeing ways in which things can be done in the future.
Oh, I *totally* agree with what you're saying. My question is how you
keep the kids from just glancing at it and going "this is lame!" and
going back to playing Angry Birds or something.
>>> You certainly can do system-level programming on the RPi. How do you
>>> think you get a kernel developed to run on it? ;)
>>
>> You're aware that to this day, the OS includes a closed-source binary
>> blob that only people who sign an NDA are allowed to look inside, right?
>> Literally, you cannot operate the GPU without signing an NDA or using
>> closed-source code. And since this is a mobile phone SoC, the GPU
>> controls the CPU, not the other way around...
>
> Yes, but that's true on a lot of PCs that run Linux as well. That
> doesn't mean you can't do system-level programming on it.
Thanks to backwards compatibility, every IBM PC-compatible starts up in
8080 emulation mode, and has a BIOS that lets you do stuff without even
knowing what model of video card you have. Even then, it surely has 100%
VGA register compatibility, so you can program it that way.
On the Pi, until you poke the GPU, the CPU isn't even *turned on*...
> I think there's a lot you can do that's interesting without any video at
> all.
Oh, really?
[That maybe sounded sarcastic. It wasn't meant to.]
Clearly you've got different ideas to me... What kinda thing are you
thinking?
[Genuinely interested here.]
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On 10/27/2015 6:58 PM, Orchid Win7 v1 wrote:
>> I think there's a lot you can do that's interesting without any video at
>> all.
>
> Oh, really?
>
> [That maybe sounded sarcastic. It wasn't meant to.]
>
> Clearly you've got different ideas to me... What kinda thing are you
> thinking?
>
> [Genuinely interested here.]
Break codes, calculate ballistic trajectories, solve engineering
problems. Run the finances for Lyons tea house. Text processing and games.
And this:
https://plus.google.com/photos/+KenShirriff/albums/6116650756716708097/6116650759320217970?pid=6116650759320217970&oid=106338564628446721517
--
Regards
Stephen
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On 10/27/2015 7:50 PM, Stephen wrote:
>
https://plus.google.com/photos/+KenShirriff/albums/6116650756716708097/6116650759320217970?pid=6116650759320217970&oid=106338564628446721517
>
>
Source:
http://www.righto.com/2015/03/12-minute-mandelbrot-fractals-on-50.htmlhttp://www.righto.com/2015/03/12-minute-mandelbrot-fractals-on-50.html
--
Regards
Stephen
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On 10/27/2015 7:52 PM, Stephen wrote:
> Source:
>
http://www.righto.com/2015/03/12-minute-mandelbrot-fractals-on-50.htmlhttp://www.righto.com/2015/03/12-minute-mandelbrot-fractals-on-50.html
>
>
Bugrit!
http://www.righto.com/2015/03/12-minute-mandelbrot-fractals-on-50.html
--
Regards
Stephen
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On 27/10/2015 07:53 PM, Stephen wrote:
> http://www.righto.com/2015/03/12-minute-mandelbrot-fractals-on-50.html
Qui-binary...?
My mind is blown.
As an aside, Hackaday.io seems to be full of people building computers
"from scratch", using only individual logic gates. One guy claimed to be
building a computer from nothing but 7400s...
...until you realise that he means the members of the 7400 family that
implement entire counters, encoders, decoders, latches, etc.
Another guy claimed to by building a computer from discrete
transistors... until you realise that he's using an Arduino to control
it. Wuh??
It's interesting to me that the IBM 1401 appears to be a *real* computer
made only from discrete transistors. I'd always assumed that such a
thing would fill an entire warehouse. But it doesn't actually look all
that big...
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On 27/10/2015 07:50 PM, Stephen wrote:
> On 10/27/2015 6:58 PM, Orchid Win7 v1 wrote:
>>> I think there's a lot you can do that's interesting without any video at
>>> all.
>>
>> Oh, really?
>>
>> [That maybe sounded sarcastic. It wasn't meant to.]
>>
>> Clearly you've got different ideas to me... What kinda thing are you
>> thinking?
>>
>> [Genuinely interested here.]
>
> Break codes, calculate ballistic trajectories, solve engineering
> problems. Run the finances for Lyons tea house.
Not sure too many children would be interested in any of those.
> Text processing and games.
Interesting without display capabilities. ;-)
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On 27/10/2015 07:53 PM, Stephen wrote:
> http://www.righto.com/2015/03/12-minute-mandelbrot-fractals-on-50.html
Only just finished reading this.
Man, that is some special brand of craziness, right there. Mental stuff.
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On Tue, 27 Oct 2015 18:58:19 +0000, Orchid Win7 v1 wrote:
>> Nothing else really plugged in, either. HDMI, external hard drive,
>> power. Wireless keyboard/mouse combo that I generally don't use.
>
> At that point, doesn't it kinda make it look like *the screen* is all
> the smarts? Not the inconspicuous little box in the corner?
Not really, but then again, I connect the HDMI to a receiver that then
sends the output to a projector. So my "screen" is a 10' diagonal image
projected on a white wall.
But it doesn't really matter.
> Oh, I *totally* agree with what you're saying. My question is how you
> keep the kids from just glancing at it and going "this is lame!" and
> going back to playing Angry Birds or something.
By making it interesting, which is done by making it relevant. A lot of
kids are curious about stuff like that.
>> Yes, but that's true on a lot of PCs that run Linux as well. That
>> doesn't mean you can't do system-level programming on it.
>
> Thanks to backwards compatibility, every IBM PC-compatible starts up in
> 8080 emulation mode, and has a BIOS that lets you do stuff without even
> knowing what model of video card you have. Even then, it surely has 100%
> VGA register compatibility, so you can program it that way.
>
> On the Pi, until you poke the GPU, the CPU isn't even *turned on*...
Mine turns on when I plug it in, before the OS is done. That's firmware-
level stuff, generally not the sort of thing I think of with "system-
level" programming.
>> I think there's a lot you can do that's interesting without any video
>> at all.
>
> Oh, really?
>
> [That maybe sounded sarcastic. It wasn't meant to.]
>
> Clearly you've got different ideas to me... What kinda thing are you
> thinking?
>
> [Genuinely interested here.]
Web hosting is the most obvious example. Music streaming, controlling
home automation - lots of IoT-related things, actually.
Jim
--
"I learned long ago, never to wrestle with a pig. You get dirty, and
besides, the pig likes it." - George Bernard Shaw
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On 10/27/2015 8:31 PM, Orchid Win7 v1 wrote:
> On 27/10/2015 07:53 PM, Stephen wrote:
>> http://www.righto.com/2015/03/12-minute-mandelbrot-fractals-on-50.html
>
> Qui-binary...?
>
> My mind is blown.
>
I know and I thought BCD was strange.
>
> As an aside, Hackaday.io seems to be full of people building computers
> "from scratch", using only individual logic gates. One guy claimed to be
> building a computer from nothing but 7400s...
>
> ....until you realise that he means the members of the 7400 family that
> implement entire counters, encoders, decoders, latches, etc.
>
I hope he has a big power supply and lots of fans.
In the mid 70's I built a digital clock out of TTL. It needed 25 amps at
5 volts to drive the logic. A couple of years later I built one out of
CMOS and that would run for an hour on a PP3 battery. (It was mains
powered the battery was for backup.)
> Another guy claimed to by building a computer from discrete
> transistors... until you realise that he's using an Arduino to control
> it. Wuh??
>
The first machine I worked on was the Honeywell H516. It used discrete
components not ICs.
> It's interesting to me that the IBM 1401 appears to be a *real* computer
> made only from discrete transistors. I'd always assumed that such a
> thing would fill an entire warehouse. But it doesn't actually look all
> that big...
That is a media exaggeration. They were forever showing images of
computer systems in enormous clean rooms with technicians in white coats.
One company I worked for had an old PDP 8. It fitted inside a 19 inch
cabinet. I only once opened the door to look at the guts. I then prayed
it would never break. ;-)
> Only just finished reading this.
>
> Man, that is some special brand of craziness, right there. Mental stuff.
Funnily enough. His project reminded me of you. Did you not once write
programs in PostScript or Printer Command Language?
--
Regards
Stephen
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On 10/27/2015 8:32 PM, Orchid Win7 v1 wrote:
> On 27/10/2015 07:50 PM, Stephen wrote:
>> On 10/27/2015 6:58 PM, Orchid Win7 v1 wrote:
>>>> I think there's a lot you can do that's interesting without any
>>>> video at
>>>> all.
>>>
>>> Oh, really?
>>>
>>> [That maybe sounded sarcastic. It wasn't meant to.]
>>>
>>> Clearly you've got different ideas to me... What kinda thing are you
>>> thinking?
>>>
>>> [Genuinely interested here.]
>>
>> Break codes, calculate ballistic trajectories, solve engineering
>> problems. Run the finances for Lyons tea house.
>
> Not sure too many children would be interested in any of those.
Calculating ballistic trajectories and blowing up your target sounds
like fun.
>
>> Text processing and games.
>
> Interesting without display capabilities. ;-)
Did not say that. You said without video.
The output was on a Teletype or a printer.
I played a graphical golf game that used a printer to show the hole and
where the ball had landed.
Thinking about it and looking up Google. I think that many of these
games were inhouse programs and not available to the public.
--
Regards
Stephen
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On 10/27/2015 11:48 PM, Jim Henderson wrote:
> Web hosting is the most obvious example. Music streaming, controlling
> home automation - lots of IoT-related things, actually.
Disturbing. You are looking to the future and I looked to the past.
I must watch out for that.
--
Regards
Stephen
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Am 28.10.2015 um 08:56 schrieb Stephen:
>> As an aside, Hackaday.io seems to be full of people building computers
>> "from scratch", using only individual logic gates. One guy claimed to be
>> building a computer from nothing but 7400s...
>>
>> ....until you realise that he means the members of the 7400 family that
>> implement entire counters, encoders, decoders, latches, etc.
Fair enough, as far as I'm concerned.
> I hope he has a big power supply and lots of fans.
> In the mid 70's I built a digital clock out of TTL. It needed 25 amps at
> 5 volts to drive the logic. A couple of years later I built one out of
> CMOS and that would run for an hour on a PP3 battery. (It was mains
> powered the battery was for backup.)
I suspect the guy in question wouldn't be using classic TTL (where on
Earth would you get those nowadays, anyway), but rather LS-TTL, cutting
power consumption to 20%.
I for one wouldn't use 7400-family chips anyway, and instead go for a
CPLD (or, more likely, a collection thereof). Makes it much easier to
make minor design changes even after the circuitry has been wired.
> Funnily enough. His project reminded me of you. Did you not once write
> programs in PostScript or Printer Command Language?
PostScript is fun! Especially since it comes with high-resolution
graphics output fully integrated ;)
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On 10/28/2015 10:45 AM, clipka wrote:
> Am 28.10.2015 um 08:56 schrieb Stephen:
>
>>> As an aside, Hackaday.io seems to be full of people building computers
>>> "from scratch", using only individual logic gates. One guy claimed to be
>>> building a computer from nothing but 7400s...
>>>
>>> ....until you realise that he means the members of the 7400 family that
>>> implement entire counters, encoders, decoders, latches, etc.
>
> Fair enough, as far as I'm concerned.
>
Not worth mentioning unless it was built only using NAND gates. Now that
would be something. ;-)
>> I hope he has a big power supply and lots of fans.
>> In the mid 70's I built a digital clock out of TTL. It needed 25 amps at
>> 5 volts to drive the logic. A couple of years later I built one out of
>> CMOS and that would run for an hour on a PP3 battery. (It was mains
>> powered the battery was for backup.)
>
> I suspect the guy in question wouldn't be using classic TTL (where on
> Earth would you get those nowadays, anyway), but rather LS-TTL, cutting
> power consumption to 20%.
>
This was about 40 years ago* and I was limited to what I could borrow
from the production line. :-)
From what I can remember of the circuit. It was mostly shift registers
and divide-by counters built from D type flip Flops. Ending up driving
Nixie Tubes for the display. (I worked for Boroughs at the time and
there were a few lying around.)
*
I did not invent my Tardis until a few years later. ;-)
> I for one wouldn't use 7400-family chips anyway, and instead go for a
> CPLD (or, more likely, a collection thereof). Makes it much easier to
> make minor design changes even after the circuitry has been wired.
>
>
How about a LM8560? Or if you want to push the boat out and spend USD 4
http://www.ecyberspaces.com/productsview.asp?id=3179
>> Funnily enough. His project reminded me of you. Did you not once write
>> programs in PostScript or Printer Command Language?
>
> PostScript is fun! Especially since it comes with high-resolution
> graphics output fully integrated ;)
>
That raises the question. If Pov will not contemplate using a GPU. How
about using a printer to do some calculations? :-P
--
Regards
Stephen
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Am 28.10.2015 um 13:07 schrieb Stephen:
>> I for one wouldn't use 7400-family chips anyway, and instead go for a
>> CPLD (or, more likely, a collection thereof). Makes it much easier to
>> make minor design changes even after the circuitry has been wired.
>
> How about a LM8560? Or if you want to push the boat out and spend USD 4
> http://www.ecyberspaces.com/productsview.asp?id=3179
Nah, I'm talking about re-inventing the computer here, not throwing
together a device intended to be mistaken for a suitcase bomb.
>>> Funnily enough. His project reminded me of you. Did you not once write
>>> programs in PostScript or Printer Command Language?
>>
>> PostScript is fun! Especially since it comes with high-resolution
>> graphics output fully integrated ;)
>
> That raises the question. If Pov will not contemplate using a GPU. How
> about using a printer to do some calculations? :-P
Using the printer as a coprocessor is a rather moot idea, unless you
also include a scanner in the system design; there's no other way to get
data from the printer back into the computer.
You /could/ of course make a PostScript printer do some raytracing
entirely on its own. But I was a bit disappointed by the computing
performance of the printer I once used for generating a printout of the
Mandelbrot set, so I'll probably not pursue this project any further...
Also, I guess we won't get real-time raytracing capabilities out of a
printer anytime soon ;)
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On 10/28/2015 1:11 PM, clipka wrote:
> Am 28.10.2015 um 13:07 schrieb Stephen:
>
>>> I for one wouldn't use 7400-family chips anyway, and instead go for a
>>> CPLD (or, more likely, a collection thereof). Makes it much easier to
>>> make minor design changes even after the circuitry has been wired.
>>
>> How about a LM8560? Or if you want to push the boat out and spend USD 4
>> http://www.ecyberspaces.com/productsview.asp?id=3179
>
> Nah, I'm talking about re-inventing the computer here, not throwing
> together a device intended to be mistaken for a suitcase bomb.
>
>
That thought had crossed my mind too. When I worked on the rigs I got
the job of replacing all the batteries in the Bed Head Units every year.
(A bad job given to me by a small minded boss. Little did he think that
it gave me carte blanche to order hundreds of AA batteries and the
opportunity to skive in the accommodation module for days on end. That
showed me who was boss. :-) )
>>
>> That raises the question. If Pov will not contemplate using a GPU. How
>> about using a printer to do some calculations? :-P
>
> Using the printer as a coprocessor is a rather moot idea, unless you
> also include a scanner in the system design; there's no other way to get
> data from the printer back into the computer.
>
No problem for me there. :-)
> You /could/ of course make a PostScript printer do some raytracing
> entirely on its own. But I was a bit disappointed by the computing
> performance of the printer I once used for generating a printout of the
> Mandelbrot set, so I'll probably not pursue this project any further...
>
> Also, I guess we won't get real-time raytracing capabilities out of a
> printer anytime soon ;)
>
I did not think that it would be a runner. ;)
It takes forever for my printer to start printing after I've sent a page
over WiFi.
But good to know that the IoT will sometime be a rendering farm.
--
Regards
Stephen
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On Wed, 28 Oct 2015 08:07:34 +0000, Stephen wrote:
> On 10/27/2015 11:48 PM, Jim Henderson wrote:
>> Web hosting is the most obvious example. Music streaming, controlling
>> home automation - lots of IoT-related things, actually.
>
> Disturbing. You are looking to the future and I looked to the past.
> I must watch out for that.
Hehehehehe.
Jim
--
"I learned long ago, never to wrestle with a pig. You get dirty, and
besides, the pig likes it." - George Bernard Shaw
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On 10/28/2015 4:09 PM, Jim Henderson wrote:
> On Wed, 28 Oct 2015 08:07:34 +0000, Stephen wrote:
>
>> On 10/27/2015 11:48 PM, Jim Henderson wrote:
>>> Web hosting is the most obvious example. Music streaming, controlling
>>> home automation - lots of IoT-related things, actually.
>>
>> Disturbing. You are looking to the future and I looked to the past.
>> I must watch out for that.
>
> Hehehehehe.
>
Just you wait. It comes to us all. :-P
Wait one.
Thinking about it. I'm glad that my time is when it is. I despair when I
see the way the world is going.
If I am asked what I want to be on the next turn of the wheel. I will
say. "A rock." And I don't mean St. Peter.
--
Regards
Stephen
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On Wed, 28 Oct 2015 16:36:08 +0000, Stephen wrote:
> On 10/28/2015 4:09 PM, Jim Henderson wrote:
>> On Wed, 28 Oct 2015 08:07:34 +0000, Stephen wrote:
>>
>>> On 10/27/2015 11:48 PM, Jim Henderson wrote:
>>>> Web hosting is the most obvious example. Music streaming,
>>>> controlling home automation - lots of IoT-related things, actually.
>>>
>>> Disturbing. You are looking to the future and I looked to the past.
>>> I must watch out for that.
>>
>> Hehehehehe.
>>
>>
> Just you wait. It comes to us all. :-P
>
> Wait one.
Waiting. ;)
But in technology, I see this all the time - IoT isn't a new thing,
really - I remember seeing networked coffee makers, VCRs, and microwave
ovens back in the 90's. It didn't catch on then, but the demo was pretty
cool.
The idea of on-demand programming was something I was first introduced to
by someone who worked at NBC back in the mid 90's as well. He described
pretty much what we see now with Netflix and other streaming/on-demand
video services.
> Thinking about it. I'm glad that my time is when it is. I despair when I
> see the way the world is going.
I think we all reach that point eventually.
> If I am asked what I want to be on the next turn of the wheel. I will
> say. "A rock." And I don't mean St. Peter.
I wouldn't have guessed that. Or maybe I would have. ;)
Jim
--
"I learned long ago, never to wrestle with a pig. You get dirty, and
besides, the pig likes it." - George Bernard Shaw
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On 28/10/2015 07:56 AM, Stephen wrote:
> On 10/27/2015 8:31 PM, Orchid Win7 v1 wrote:
>> Qui-binary...?
>>
>> My mind is blown.
>>
> I know and I thought BCD was strange.
BCD is one thing. LSD...?!
>> As an aside, Hackaday.io seems to be full of people building computers
>> "from scratch", using only individual logic gates. One guy claimed to be
>> building a computer from nothing but 7400s...
>>
>> ....until you realise that he means the members of the 7400 family that
>> implement entire counters, encoders, decoders, latches, etc.
>>
>
> I hope he has a big power supply and lots of fans.
Heh, yeah, well...
>> It's interesting to me that the IBM 1401 appears to be a *real* computer
>> made only from discrete transistors. I'd always assumed that such a
>> thing would fill an entire warehouse. But it doesn't actually look all
>> that big...
>
> That is a media exaggeration. They were forever showing images of
> computer systems in enormous clean rooms with technicians in white coats.
> One company I worked for had an old PDP 8. It fitted inside a 19 inch
> cabinet. I only once opened the door to look at the guts. I then prayed
> it would never break. ;-)
I often wonder... like, how much did [famous obsolete computer] actually
cost? What did it physically look like? What were its technical
capabilities? It's very hard to gather a general overview of this type
of data.
For that matter, how many FLOPS can you get out of an Inter Core i7? I
have absolutely no idea; it seems very hard to find data for this...
>> Only just finished reading this.
>>
>> Man, that is some special brand of craziness, right there. Mental stuff.
>
> Funnily enough. His project reminded me of you. Did you not once write
> programs in PostScript or Printer Command Language?
PostScript. And it wasn't *once*. ;-)
Actually, I did start trying to write a PostScript *interpreter*, to
make debugging this stuff easier! It turns out the language has a lot
more edge-cases than you'd think though...
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>> That raises the question. If Pov will not contemplate using a GPU. How
>> about using a printer to do some calculations? :-P
Oh God, think of the massacre...! O_O
> Using the printer as a coprocessor is a rather moot idea, unless you
> also include a scanner in the system design; there's no other way to get
> data from the printer back into the computer.
You know, PostScript does actually have file I/O capabilities. Sure,
I've never seen any system that actually *implements* them... but it
literally does have commands for reading and writing files, doing
terminal access, etc.
> You /could/ of course make a PostScript printer do some raytracing
> entirely on its own. But I was a bit disappointed by the computing
> performance of the printer I once used for generating a printout of the
> Mandelbrot set, so I'll probably not pursue this project any further...
The last printer I looked at was powered by a 200 MHz Pentium II. This
was in the days when the Pentium IV was considered obsolete... (We all
know parts never stop being used, they just move down the food chain.)
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On 28/10/2015 06:06 PM, Jim Henderson wrote:
> But in technology, I see this all the time - IoT isn't a new thing,
> really - I remember seeing networked coffee makers, VCRs, and microwave
> ovens back in the 90's. It didn't catch on then, but the demo was pretty
> cool.
HTTP 418: I'm a teapot.
https://tools.ietf.org/html/rfc2324
Seriously. There is a defined HTTP status code for interacting with an
IoT teapot.
> The idea of on-demand programming was something I was first introduced to
> by someone who worked at NBC back in the mid 90's as well. He described
> pretty much what we see now with Netflix and other streaming/on-demand
> video services.
Some day, maybe I'll try that.
Ah, who am I kidding? I'll just sit here surfing YouTube...
(I'm still puzzled as to why YouTube can actually exist. But that's
another story.)
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On 10/28/2015 6:06 PM, Jim Henderson wrote:
>> Just you wait. It comes to us all.:-P
>> >
>> >Wait one.
> Waiting.;)
>
Your custom is important to us.
Please listen to this elevator musak...
> But in technology, I see this all the time - IoT isn't a new thing,
> really - I remember seeing networked coffee makers, VCRs, and microwave
> ovens back in the 90's. It didn't catch on then, but the demo was pretty
> cool.
>
> The idea of on-demand programming was something I was first introduced to
> by someone who worked at NBC back in the mid 90's as well. He described
> pretty much what we see now with Netflix and other streaming/on-demand
> video services.
>
If you read any amount of SF the infinite monkeys got there first.
Mobile (cell) phones excepted.
Strange how that got missed by everyone except Dick Tracy.
>> >Thinking about it. I'm glad that my time is when it is. I despair when I
>> >see the way the world is going.
> I think we all reach that point eventually.
>
So it seems. Just glad I'm normal in one aspect. ;-)
>> >If I am asked what I want to be on the next turn of the wheel. I will
>> >say. "A rock." And I don't mean St. Peter.
> I wouldn't have guessed that. Or maybe I would have.;)
You have a head start. :-)
I was talking about Edinburgh Rock. The best thing to come out of
Edinburgh, the road to Glasgow, excluded. ;-)
--
Regards
Stephen
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On 10/28/2015 6:08 PM, Orchid Win7 v1 wrote:
>
> I often wonder... like, how much did [famous obsolete computer] actually
> cost? What did it physically look like? What were its technical
> capabilities? It's very hard to gather a general overview of this type
> of data.
>
PDP-8 1965 $18,500 12 ~50,000 The smallest and least expensive PDP
http://homepage.cs.uiowa.edu/~jones/pdp8/faqs/
> For that matter, how many FLOPS can you get out of an Inter Core i7? I
> have absolutely no idea; it seems very hard to find data for this...
>
So it is.
http://www.tomshardware.co.uk/forum/262886-28-core-gflops-benchmark
>>
>> Funnily enough. His project reminded me of you. Did you not once write
>> programs in PostScript or Printer Command Language?
>
> PostScript. And it wasn't *once*. ;-)
>
> Actually, I did start trying to write a PostScript *interpreter*, to
> make debugging this stuff easier! It turns out the language has a lot
> more edge-cases than you'd think though...
One edge-case is more than I ken.
I would ask what an edge-case is but then you would say that I can't
Google. :-)
--
Regards
Stephen
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On 10/28/2015 6:11 PM, Orchid Win7 v1 wrote:
>>> That raises the question. If Pov will not contemplate using a GPU. How
>>> about using a printer to do some calculations? :-P
>
> Oh God, think of the massacre...! O_O
Think of the Amazon Rain Forests devastated as it outputs its
calculations to hardcopy.
--
Regards
Stephen
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On Wed, 28 Oct 2015 18:08:56 +0000, Orchid Win7 v1 wrote:
> I often wonder... like, how much did [famous obsolete computer] actually
> cost? What did it physically look like? What were its technical
> capabilities? It's very hard to gather a general overview of this type
> of data.
Google is really useful. I hear they have pictures and everything. ;)
> For that matter, how many FLOPS can you get out of an Inter Core i7? I
> have absolutely no idea; it seems very hard to find data for this...
Depends on the speed of the CPU and the number of cores, but a google
search for "intel core i7 flops" turned up useful results.
Jim
--
"I learned long ago, never to wrestle with a pig. You get dirty, and
besides, the pig likes it." - George Bernard Shaw
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On Wed, 28 Oct 2015 18:17:38 +0000, Orchid Win7 v1 wrote:
> On 28/10/2015 06:06 PM, Jim Henderson wrote:
>> But in technology, I see this all the time - IoT isn't a new thing,
>> really - I remember seeing networked coffee makers, VCRs, and microwave
>> ovens back in the 90's. It didn't catch on then, but the demo was
>> pretty cool.
>
> HTTP 418: I'm a teapot.
>
> https://tools.ietf.org/html/rfc2324
>
> Seriously. There is a defined HTTP status code for interacting with an
> IoT teapot.
It's funny, yeah - but the history of that error code isn't really IoT,
more like RFC 1149. 418 was defined in the HTCPCP/1.0 protcool, defined
in the referenced RFC as an April Fool's day joke in 1998.
It's a fun read. (Did I mention that I work with a product that secures
websites, and HTTP geek stuff is what I currently work with daily? ;) )
>> The idea of on-demand programming was something I was first introduced
>> to by someone who worked at NBC back in the mid 90's as well. He
>> described pretty much what we see now with Netflix and other
>> streaming/on-demand video services.
>
> Some day, maybe I'll try that.
Definitely worth it, IMHO.
> Ah, who am I kidding? I'll just sit here surfing YouTube...
>
> (I'm still puzzled as to why YouTube can actually exist. But that's
> another story.)
People want to publish videos. Youtube gives them a platform to do that.
And gives Google another platform to push advertising on.
It's about that simple, really. :)
Jim
--
"I learned long ago, never to wrestle with a pig. You get dirty, and
besides, the pig likes it." - George Bernard Shaw
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On Wed, 28 Oct 2015 18:40:04 +0000, Stephen wrote:
> On 10/28/2015 6:06 PM, Jim Henderson wrote:
>>> Just you wait. It comes to us all.:-P
>>> >
>>> >Wait one.
>> Waiting.;)
>>
>>
> Your custom is important to us.
> Please listen to this elevator musak...
Only if it's good. Then again, you said "musak", so it probably isn't. :P
>> The idea of on-demand programming was something I was first introduced
>> to by someone who worked at NBC back in the mid 90's as well. He
>> described pretty much what we see now with Netflix and other
>> streaming/on-demand video services.
>>
> If you read any amount of SF the infinite monkeys got there first.
> Mobile (cell) phones excepted.
Star Trek communicators. The design of the Motorola Flip phone allegedly
was taken from Star Trek.
> Strange how that got missed by everyone except Dick Tracy.
More the Apple Watch, but yeah.
>>> >Thinking about it. I'm glad that my time is when it is. I despair
>>> >when I see the way the world is going.
>> I think we all reach that point eventually.
>>
>>
> So it seems. Just glad I'm normal in one aspect. ;-)
LOL
>>> >If I am asked what I want to be on the next turn of the wheel. I will
>>> >say. "A rock." And I don't mean St. Peter.
>> I wouldn't have guessed that. Or maybe I would have.;)
>
> You have a head start. :-)
>
> I was talking about Edinburgh Rock. The best thing to come out of
> Edinburgh, the road to Glasgow, excluded. ;-)
I'll have to remember that one the next time I'm talking with friends who
live in Scotland. Especially the ones who live in Edinburgh. ;)
Jim
--
"I learned long ago, never to wrestle with a pig. You get dirty, and
besides, the pig likes it." - George Bernard Shaw
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On 10/28/2015 7:06 PM, Jim Henderson wrote:
> On Wed, 28 Oct 2015 18:40:04 +0000, Stephen wrote:
>
>>>
>>>
>> Your custom is important to us.
>> Please listen to this elevator musak...
>
> Only if it's good. Then again, you said "musak", so it probably isn't. :P
>
Elevator music is another name for musak. Which is often heard when on
hold. Or in a hotel foyer.
>> If you read any amount of SF the infinite monkeys got there first.
>> Mobile (cell) phones excepted.
>
> Star Trek communicators. The design of the Motorola Flip phone allegedly
> was taken from Star Trek.
>
More a walkie talkie than a phone that everyone uses. I think.
>> Strange how that got missed by everyone except Dick Tracy.
>
> More the Apple Watch, but yeah.
>
Yip!
>>
>> I was talking about Edinburgh Rock. The best thing to come out of
>> Edinburgh, the road to Glasgow, excluded. ;-)
>
> I'll have to remember that one the next time I'm talking with friends who
> live in Scotland. Especially the ones who live in Edinburgh. ;)
>
It is a steal from Dr Johnson.
--
Regards
Stephen
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On Wed, 28 Oct 2015 19:43:08 +0000, Stephen wrote:
>> Only if it's good. Then again, you said "musak", so it probably isn't.
>> :P
>>
>>
> Elevator music is another name for musak. Which is often heard when on
> hold. Or in a hotel foyer.
So "elevator musak" is redundant. ;)
>>> If you read any amount of SF the infinite monkeys got there first.
>>> Mobile (cell) phones excepted.
>>
>> Star Trek communicators. The design of the Motorola Flip phone
>> allegedly was taken from Star Trek.
>>
>>
> More a walkie talkie than a phone that everyone uses. I think.
Well, from a design standpoint, though, that's what inspired Motorola, I
hear.
>>> I was talking about Edinburgh Rock. The best thing to come out of
>>> Edinburgh, the road to Glasgow, excluded. ;-)
>>
>> I'll have to remember that one the next time I'm talking with friends
>> who live in Scotland. Especially the ones who live in Edinburgh. ;)
>>
>>
> It is a steal from Dr Johnson.
Oh, sure, try and defer the credit. ;)
Jim
--
"I learned long ago, never to wrestle with a pig. You get dirty, and
besides, the pig likes it." - George Bernard Shaw
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