ARMX6 vs. Raspberry Pi

For me, I dream of PCIe, but for tinkering reasons. I am ashamed to admit that I literally dream about the titanium board. Can’t get the stupid thing out of my mind and I want it so bad! Curse you Elesar! What have you done to me!?

Perhaps Titanium is the computing equivalent of a musical ear worm for you? You’re welcome!

Andrew enabled the Serial port on the ARMX6 for me (including an external DB9 port), so I can actually use it for my work. That was the one real advantage of the TiMachine for me – but R-Com enlightened me with this hidden feature on the ARMX6.

A small word of caution on serial ports: the Wandboard (used in the ARMX6) provides the RTS/CTS lines, but is missing the other handshaking lines which are often required in more specialist applications – for example, for a (fax) modem, some serial mice, and similar industrial control.

From the Titanium TRM
From the Wandboard user guide

Not relevant in many cases when communicating with another computer, but not all DB9’s are what they seem.

Thanks for that Rob. I think there have been a couple of revisions to the serial stuff over the years. Certainly our industrial customers have had no problems with ARMX6 serial, and they were the ones who paid for that work, nor users with fax modems plugged in. Indeed, several users actually pull multiple serials from the board (it supports up to three if you’re prepared to fiddle/solder/mod). But, as you say, it may be that folks haven’t needed some aspect. There’s certainly no outstanding fault reports.

There is no Organizer Pro. However, there is an Organizer application, but I know of no reason why any recent version would not work on an RPi3, and we have had no reports of any RPi3 problems.

On my Pi3 the ‘Notes’ section crashes (and I get a crash for every other open program afterwards), when I add notes longer than one page, using a lot of coloured URL’s in it. On the Pi 1, it just does not show any page after the first (so there are no crashes). I reported that issue a few weeks ago via mail.

won’t notice that it’s only 24Hz

My experience is different with low refresh rates, especially when pushing around a lot of graphics. But maybe it does not affect/annoy you as much. Context is key.

tempted by by the ARMX6 diy kit, but benchmarks are putting me off a little as it doesn’t feel like much of an upgrade from the RPi3

I think both machines are ‘feeling’ to be on par in daily use. Benchmarks might show a different picture, but not everything that can be measured is truly experienced. So, if the Pi3 works fine – no worries. If it doesn’t – the ARMX6 is a fine (more expensive) alternative. Each his own, I would say.

A small word of caution on serial ports

Good point, fortunately irrelevant in my case. It is used only for CLI access on routers. But might be an issue for some people, if it still exists.

But maybe it does not affect/annoy you as much.

I can’t even see the effect.

In my youth cinema film ran at 24 frames per second (double flashed so it flickered at 48, but only giving you new images at 24), and telly still runs at 25 (interlaced to create a sort of 50). The poor resolution always did bug me – like looking through someone else’s glasses and being unable to focus – but I’ve never noticed the refresh rate at all.

The effect becomes more obvious, when moving windows around the screen, or moving larger pictures within a window. When using text or typing, or reading, even web browsing, you won’t see much of a difference.

It may become obvious to you, but I simply can’t see it at all, whatever this effect you’re seeing is. I drag a window containing a picture; it moves. I can put it exactly where I want it, as quick as I like. I really don’t know what effect you’re seeing.

Fast moving objects (with hard edges) in videos do acquire a series of “edges,” instead of a single moving edge, but I don’t notice it when dragging windows.

Persistence of vison is the thing to look at.¹

Which, with a 12 frames per second typical limit, shouldn’t actually be an issue in these circumstances.

¹ First link I got when looking for info on the effect.

Re: Organizer

I reported that issue a few weeks ago via mail.

Sorry, but I have seen nothing here. Please can you re-send your report to the technical support contact in Help. I suspect it is nothing to do with the RPi3.

Sorry, but I have seen nothing here.

Neither have I but I am using a nutpi version.

Steve: well, exactly. I can’t hear the difference between digital and analogue music, either (except sometimes when one or the other has actual defects).

Rewinding slightly to the serial port & supported/enabled pins I do wonder why pins 4 +6 are not simply linked on the Wandboard.
Where DTR/DSR is not used the system doesn’t care and where it is used (like old PeeCee implementations¹) the PeeCee serial link actually works without extra (sometimes arcane) wiring in the link cable.

¹ It is (was?) actually more widespread and I had several arguments about RS232 pinning with install/support staff from companies including IBM where I tended to make two leads where one was their specification and the other one my all pins connected version. Mine worked. Often it was the DTR/DSR element that was the problem.

Which, with a 12 frames per second typical limit, shouldn’t actually be an issue in these circumstances.

I thin there is a difference between being capable of seeing different images, and being capable of detecting flickering.

In my youth cinema film ran at 24 frames per second (double flashed so it flickered at 48, but only giving you new images at 24), and telly still runs at 25 (interlaced to create a sort of 50).

Broadcast television of the old school variety ran at 50Hz. While the picture was only technically 25 frames per second, it being sent as two interlaced fields meant the on-screen refresh went at 50Hz.

Cinema normally ran at 48Hz. The film advanced at 24 frames per second, however the shutter in front of the lamp opened twice per frame. Why not just open longer? It’s a trade off between illuminating the screen and burning the film. And with reference to Steve’s link above, it was found that flashing the image at 24Hz made people feel ill. Double-flashing, on the other hand, worked. Because there is a very definite difference between persistence of vision (in ciné terms, anything over ~16fps is “good enough” – remember the old Super8 cameras?) and how people respond to flicker.

Some people can “see” flickering that others simply cannot see. When I was young, I used to be able to tell when fluo tubes were coming to the end of their lives. To me, they would practically be turning on and off. To others? Well, they thought I was crazy. I rarely see this now. I don’t know if that’s age making me less sensitive, or advances in lighting technology.
I can also see EDF sending signalling pulses down the electric wires at certain times of the day (noon and 8pm quite often). My mother and I seem to be among the few that can see this. I’ve asked at work in times when it’s flickered the lights enough to be akin to a brownout, yet nobody else notices. Not in my head: http://matthieu.benoit.free.fr/tempo/Pulsadis.htm http://pulsadis.free.fr/

I can’t hear the difference between digital and analogue music, either

I remember many years ago all the scare stories about how much it would affect people to listen to digital music because human ears are not built to deal with sound expressed in binary form. It was amusing even then, showing quite a lack of understanding of how sound is represented digitally, and ideas like that helped spawn an industry of special headphones designed for digital music. Hmmm… It’s not the headphones that matter, it’s the quality of the DAC!

For me, there is a lot of difference between analogue and digital. For a start, digital usually runs at the speed it is supposed to and without unwanted disturbance. For example, a cassette tape that was in a Walkman when moving would spool up unevenly, and that tape, when played at home, might rub slightly. Enough to make small disturbances in playback speed. Records? Even with a cover, there’s always going to be dust or fuzz somewhere to make crackles in the sound.
On the other hand, MP3 encoded at lower bitrates sounds pretty bad. Older hardware would create 128kbit MP3 without the clever psychoacoustic work that LAME and the like perform. So you’re left with a sound that resembles the output of a small desktop speaker placed under a terracotta plant pot. The bass is lacking, the distinction of the treble is lacking, and if your preference is something that exercises both heavily (such as symphonic metal), the end result is akin to how mushing up all the paint colours gives you a sort of murky brown. If you can imagine the aural equivalent…

As far as digital and analogue go, they each had their good points and their bad points. I love how digital video can deliver 720 and 1080 resolution video. Seriously, watching programmes on NHK World in 1080 gives a degree of clarity that is amazing. But… while NHK World burns through the bandwidth (to the tune of ~3.5GB per hour), most channels do not use that sort of bandwidth. Not even BBC. So… this brings me back to analogue. A much lower resolution (576 lines for us, and pity the Americans with a crappy ~480 lines) but a highly nuanced picture.
Tell you what. Go to a supermarket and head over to where they are selling TVs. Go look for one playing something off Bluray (probably whatever Disney flick they’re helping to promote) and look carefully at the contrast edges and the areas of flat colour (such as the sky). Notice the blockiness and the blotching. That is what is wrong with digital video. To me, a child of the analogue days, sometimes these visual artefacts are really distracting. That’s not to say that one cannot get rid of them. But one cannot get rid of them in a commercially justifiable way. It’s always going to be a trade off between bandwidth and cost and what is practically possible. This is why LPs run at 33rpm, not 45rpm. Technically, a 45 single is a much higher bandwidth sound than a 33 album, but imagine how big the album record would need to be to run at 45rpm?
Let’s not even talk about 78s! :-)

I drag a window containing a picture; it moves. I can put it exactly where I want it, as quick as I like. I really don’t know what effect you’re seeing.

I think you will see the effect if you drag a window over a picture, noticeably a complex vector drawing (the old Artworks Apple is a good example). The Pi3 does a good job, but my ARMiniX does much better. And for me, who knows no greater joy than dragging windows over complex drawings, this really makes a difference.

Not in my head: http://matthieu.benoit.free.fr/tempo/Pulsadis.htm http://pulsadis.free.fr/

I remember in the 50s an electrician coming to rewire the immersion heater, and I asked him for the redundant “black box” he took out (black bakelite).

Dismantling it revealed some electromagnetic tuned circuits consisting of “balance wheel” type magnets on jewelled bearings mounted inside coils. It was apparent that these were physically tuned to respond to pulses at specific intervals which would kick them into increasing oscillation until they tripped a set of relay-style contacts, rather heavy duty in nature. Their oscillation period would be measured in seconds rather than higher frequencies. Probably my first experience of a tuned circuit.

I deduced their purpose was to remotely control the feed to the immersion heater – a comparatively heavy current device – when demand exceeded the capacity of the local electricity board’s (as it was then) generators (I was quite clever as a child!).

On a separate but closely-related theme, I also remember the loudspeaker with a high (mains) voltage DC coil that an elderly gentleman gave me with which it was possible to hear the audio tones sent to turn on/off the streetlights whilst watching the result through the bedroom window! Cause and effect closely linked! Seeing and hearing!

Then there was the amplified crystal set with the red spot transistor, but that’s another story!

Ah, nostalgia ain’t what it used to be!

For me, there is a lot of difference between analogue and digital.

I agree the defects are different, when there are defects such as too low a bitrate with digital, or wow or flutter due to bad mechanicals with analogue, or dust etc on analogue. But clean vinyl on good equipment and MP3s at sensible bit-rates – no, I can’t tell the difference. Any difference is out the top of my hearing (~8kHz – just tested it. Not bad for 67 years old.).

I think you will see the effect if you drag a window over a picture,

I frequently do exactly that. No, I don’t notice anything other than a window moving over a picture.

I think you will see the effect if you drag a window over a picture,

I frequently do exactly that. No, I don’t notice anything other than a window moving over a picture.

Redraw rates is probably the issue for any observed effect.
If the application loading the picture handles the redraw well then there is no perceived delay in redraw. The same of course is true with plain desktop vs. bitmap image.

Skip back to an old RPC and RO4.02 with a large JPEG image as the background, anyone who didn’t perceive the redraw should probably get more than their eyes tested.

Redraw rates is probably the issue for any observed effect.

Windows 10 on a one-year-old Medion laptop…drag one filer window over the top of another, and wait for the row of overlapping images of the top window to vanish, one by one. I can’t quite count fast enough to keep up.

Used to get a similar effect on RiscPCs, yes – not as slow as Windoze 10, but very noticeable.

Used to get a similar effect on RiscPCs, yes – not as slow as Windoze 10, but very noticeable.

Worth noting that the relative processor speeds of the the two are about 1:10 and you’re pointing out that the windows offering is notably worse than the RPC.

Yup. I’m well aware of that. Crap programming somewhere in Windoze 10…and the cheapo Medion isn’t fast enough to cover for it.

The question is, is it deliberately crap to try to force you to spend more money on hardware?