I'm out of ideas for news-titles


Pretty sure we have a small surface area to put more than one ram chip at any time Grench. The CPU board is full enough as it is.
 
Can someone post up a brief synopsis of the "recent temporary confusion about the chips"?
It was a very tiny little saga:

Tony Lindgren found that he could persuade his 4 GB prototype to run two instances of memtester addressing a total of more than 2 GB (I don't think he said for how long, but there were thermal issues I think), provided he set the voltage to 1.50 V instead of 1.35 V (And used a heat sink. And made at least one other change to the configuration settings.).

For a few minutes it seemed possible that this was because the team had somehow mistakenly used the 1.50 V chips instead of the 1.35 V chips. EvilDragon wrote [1]:

I just checked the part number on the 4GB RAM chips - and indeed, it is the K4B8G1646D, which means we have the DDR3 and NOT the DDR3L version (which would be K4B8G1646Q).​

But it turns out that he was simply turned around for a moment and was reading the wrong column of the part number or the wrong line of the spec sheet or something. (The "D" and the "Q" in the 10th column indicate the chip revision; 1.35 V is indicated by the "M" in the 13th column of the part number [2].)

[1] https://pyra-handheld.com/pipermail/kernel/2017-August/001944.html
[2] http://www.samsung.com/semiconducto...mt/2016/11/DDR3_Product_guide_Oct.16[2]-0.pdf
[doublepost=1505169330,1505168974][/doublepost]
DDRxL and LPDDR are entirely different standards - LPDDR uses a custom protocol.
Thanks for the clarification.
[doublepost=1505169694][/doublepost]
I'm really fuzzy about my recollection of this - does anyone else recall those posts from ~2 years ago about this?
I too would be interested in learning the configuration of the 2 GB units. And the information in the Wiki could be made more detailed / up to date.

On the other hand, I would prefer that the time be spent debugging the 4 GB issue, finishing the hardware testing, and polishing the OS.
[doublepost=1505169887][/doublepost]
Pretty sure we have a small surface area to put more than one ram chip at any time Grench. The CPU board is full enough as it is.
Must be four chips, surely. For 4 GB, at least. The Samsung K4B8G1646D-MMK0 is 8 Gb = 1 GB. So there must be four of them for 4 GB. (Unless there's error correction; then we'd need five.) And 4000 of them have been purchased already which suggests 4 per unit, for 1000 units.
 
@Grench, I don't recall the RAM with a different pinout. I also don't remember ED saying the 1GB RAM being more expensive, although I do remember him saying he would look into it, then coming back with numbers for us, which is when serious talk about the 4GB units started.
Found it.
https://pyra-handheld.com/boards/threads/colorful-week.77519/
1. The RAM

Upgrading to 4GB or RAM was not as simple as we had hoped to, but we're now ready to test it.

What was the problem? Well, the main problem was the rare use.
The same manufacturer offering the 512MB RAM chips we use (four of them make 2GB) also offers 1GB versions, which should basically work out of the box on our current CPU board.
However, as they are not requested that often, the price for them quadruples - so 4 times the price for double the RAM.

It would be possible, but not my favourite solution.

A second solution would be to use Samsung RAM chips. They have a neat 4GB solutions using dual-channel 2GB chips.
Those require additional wiring to the SoC, so we thought at first we'd need a new CPU board for those... but then Nikolaus found out that he actually DID that wiring just in case (he just forgot about it, as that was over a year ago).

That means: We've requested samples of chips for both solutions and will put them on a current CPU board as a test.
We will also check for idle power usage, as there might be quite some differences as well.

So yep, 4GB will happen, but I hope this little information shows to you that it's not just a simple plug and play replacement as it is on a PC.

So, it makes me wonder, which method and which chips are being used in which prototypes?
 
Ok, so to get the 1GB ones from the same company would have been more expensive. Wasn't there another thread, or maybe a post buried in one, before this where he talked about possibly doing a 4GB model? I guess I could get off my ass and start digging through the old news to find out.

Either way, I vividly remember the part about the board design now. I thought "wow, way to plan ahead, he is such a smart guy", and I wanted to give him a high five.
 
Aa1) 2GB RAM visible, everything ok, memtester 1500M successful
Aa2) 2GB RAM visible, boot sometimes hangs, memtester 1500M successful
Ab1) 2GB RAM visible, everything ok, memtester 1500M successful
Ab2) 2GB RAM visible, boot sometimes hangs, memtester 1500M successful

Does the 2GB version still hang sometimes on boot?
 
Does anyone have a part number for the four 512MB chips used in the original spec (2GB Pyra)? Is it the same chip parts that are used in the Ti OMAP5432 EVM dev boards?
 
Frankly, although I personally prefer 4 GB and would pay extra for it, I'd be more than happy with 2 GB too. If it's delay the production couple of months or so, I'd rather have it sooner than have it perfect...
 
I thought the reason we were all patiently waiting is because we want it as close to perfect as they can get it.
"were" is the keyword here. Patience is finite.Though, I for one am keeping it up, while it's getting harder 'n' harder due to my phones audio jack being on the fritz. Phone in my front pocket listening to music may work fine or as often the case with every right-legged step the left channel mutes for a moment.

Where's my Pyra? I need it now - with no RAM if need be. :'(
 
All efforts are now focused on this RAM issue. Should be ok soon.
There are many of us who would like a play-by-play of how this is progressing, but also have no intention of slowing them down to document for our 'amusement' as we're all very unlikely to be able to help directly.

Need someone to find that clip from Airplane where the doctor says something to the effect of, "Good luck. We're all counting on you."
 
I would really like to help but I'm no developer i have always been interested in being one but i barely have time to sit at a pc and learn linux and hardware because of my job and my learning disability this one of my big reasons for wanting this device it makes it easier for to learn like a desktop os is makes more sense than a mobile os. But if it was in front of me i could learn it i am a hands on learner as it's called

Sent from my LG-K373 using Tapatalk
 
The mailing list isn't private.
Even ED is putting hands in the low-level stuff :^) .
Assume I'm an idiot - it shouldn't be that difficult, right?
If I wanted to be the proverbial, "fly on the wall," how would I get added to or be able to view said mailing list? I don't want to be disruptive, but I would find the process fascinating.
 
Maybe i have one funny Idea for the Pyra:

The Pyra have maybe 4 GB Stable in the Future...
...when not we have 2 GB and @EvilDragon have too many Ram Chips over...
...
...
...
..maybe EvilDragon can create an Sata to Ram Adapter for swapping Ram on the Pyra Sata?

It can be a Sort USB3 or Sata to Ram converter and it will be much faster than a "normal" USB Stick.

Which one should be faster?
Sata on the Pyra(do not know which Version we have)
or
Usb3 on the Pyra

When one Door is closing...mostly there are another Doors opening :D

And this Idea is not new:
There are Sata to Ram Adapter sold..they exist.
In our Case we need no Battery because its only Swap.

A Startup Script for creating and activating Swap on Usb/Sata automatic should be no Problem.

Shurly... its not so fast like real Ram but i think its a good Idea :D
 
All efforts are now focused on this RAM issue. Should be ok soon.
Would that that were true. :( Solving this problem systematically requires 1) skill/knowledge, 2) hardware/equipment, 3) information, and 4) time. Sadly, it seems that no one has a full set of these. Those with the first three seem to lack the fourth (and vice versa). I'm hoping that the problem will very soon be solved by random serendipity instead.
[doublepost=1505330422,1505329228][/doublepost]
Even ED is putting hands in the low-level stuff :^) .
Yup. He's applying a bit of 1) and 2), most of 3), and a bunch of 4) afforded by his vacation. Really, though, I think he ought to be going to the beach. Or doing whatever it is that dragons do in their leisure time. :)
 
Back
Top