Some PB360's picky about micro sd cards?

[tselling]

I recently picked up a used ivory PB360 to go along with my black PB360 (my 5 year old has taken a liking to the black one with the Berenstain Bears books and I thought a spare was definitely needed). It was a good deal at $94 shipped but I have had some problems that I am not sure are normal.

When I first got it, I updated the firmware from the internal memory. Then put in a spare Transcend 2gb micro SD card. It took forever for the pb360 to be detected by my PC, kept saying it needed a disk check, etc. I formatted the internal memory twice and still the same problem. I have two other micro SD cards, a 4 GB sandisk and a 2GB sandisk (this one was in my black pocketbook). The 4GB sandisk seemed to have the same problem as the 2GB transcend. The 2gb sandisk from my black pocketbook is working fine. I reflashed the 15.3 Dec 8 firmware from the 2gb sandisk and all seems to be well with the ivory PB with the 2gb sandisk card... it is dectected normally by my PC and calibre can load books (though for some reason book directories were read-only initially and I had to manually change the permissions... maybe because initially loaded on black pb360).

I put the 2GB transcend in the black PB360 and its working fine there. The black one I bought new early before the retail boxes were ready. The used ivory one I just got came with a retail box.

It seems strange that the two PB360s don't behave the same with regard to micro sd cards. So now I am wondering if the ivory one is defective in some way or if the hardware was changed in some of the PB360's affecting what micro-SD cards work? Anyone have any info or thoughts on this?

[fjtorres]

Originally Posted by tselling

It seems strange that the two PB360s don't behave the same with regard to micro sd cards. So now I am wondering if the ivory one is defective in some way or if the hardware was changed in some of the PB360's affecting what micro-SD cards work? Anyone have any info or thoughts on this?

There is some evidence, but no official word, that different batches of 360 behave differently in several ways. That is one of the challenges that has kept 15.3 in beta for months now...

[mtravellerh]

Originally Posted by fjtorres

There is some evidence, but no official word, that different batches of 360 behave differently in several ways. That is one of the challenges that has kept 15.3 in beta for months now...

fj: I think you may have hit something there. PocketBook, however does not know of different batches.

[tselling]

Originally Posted by mtravellerh

fj: I think you may have hit something there. PocketBook, however does not know of different batches.

Thats interesting about the different behavior... but I would have thought PocketBook would be aware of differences in batches. I guess its always possible that a supplier of chips had a slightly different batch.

[fjtorres]

Originally Posted by tselling

Thats interesting about the different behavior... but I would have thought PocketBook would be aware of differences in batches. I guess its always possible that a supplier of chips had a slightly different batch.

Or the assembler (Netronix?) sourced some component from alternate suppliers. Even different component batches from the same source could be subtly different and still be within spec. Could be as simple as a capacitor or a connector with different resistance.
With low-power devices just about any variation can be critical.
Modern consumer electronics are miraculous devices: it's a miracle they work at all.

[bryanzs]

I've tried 4 different microSD cards in my PB360 now - of varying sizes, manufacturers, and speed ratings - and all display an odd behavior.

I like to save the "last read page" as the shutdown image, so I can be up and reading instantly when I power on the PB360. If I use the PB360 regularly - at least once a day - I don't have any problems. But if the ebook reader sits, powered off, for a few days or more, when I boot it up it shows that last page as it loads its operating system, and then it sends me to the "home screen", where none of the files from my microSD card are displayed. If I then power off, and power back on, the unit, the files from the microSD card are then displayed, and I can go back into the book I was reading.

(There was even one card where the symptoms were all the same, except that sometimes when I got back to the home page, only _some_ - the first 10 folders, say - of my files from the microSD card could be found)

Anyone else see _this_ kind of behavior?

[tselling]

Can you give the brand, size, class of the microSD cards you have tried? Maybe the cards are marginal in speed (ie the PB360 sometimes doesn't see the card when it first boots because it times out waiting for it to be available. Anyway if you give the exact cards you have tried, others can let you know their experience with same or similar ones.

Originally Posted by bryanzs

I've tried 4 different microSD cards in my PB360 now - of varying sizes, manufacturers, and speed ratings - and all display an odd behavior.

I like to save the "last read page" as the shutdown image, so I can be up and reading instantly when I power on the PB360. If I use the PB360 regularly - at least once a day - I don't have any problems. But if the ebook reader sits, powered off, for a few days or more, when I boot it up it shows that last page as it loads its operating system, and then it sends me to the "home screen", where none of the files from my microSD card are displayed. If I then power off, and power back on, the unit, the files from the microSD card are then displayed, and I can go back into the book I was reading.

(There was even one card where the symptoms were all the same, except that sometimes when I got back to the home page, only _some_ - the first 10 folders, say - of my files from the microSD card could be found)

Anyone else see _this_ kind of behavior?

[bryanzs]

I held off on reporting this problem for some time, thinking that it would always be fixed in the next release, and/or by a different card.

I'm currently using:
RiData class 6 4GB

but have previously tried:
Kingston class 4 4GB
SanDisk class 2 16GB

and another 4GB or 8GB that I can't find right now. I suspect that it has something to do with the larger size of the cards, which I had hoped would be balanced out by the faster speed of the class 6 - but it still behaves the same.

It almost seems like, so long as there is a trickle of charge left in the card or system (ie, it's not a _really_ cold boot), then it's ok. But if all residual charge has left the card, then the PB360 doesn't have enough time to initialize it before deciding it's not there. Of course, I'm a software guy, not a hardware guy, so as far as I know there are little gremlins running around and they just don't run fast enough to reach the end of the SD card...

[fjtorres]

The Sandisk class 2 is likely to give trouble; that's an acknowledged issue.

[bryanzs]

Originally Posted by fjtorres

The Sandisk class 2 is likely to give trouble; that's an acknowledged issue.

Yes, that's why I've tried the others (with different manufacturers, size, and classes). Although "acknowledged issue" gives the impression that PocketBook is aware and agrees that there's an issue to resolve; is that really the case? Or is this just an "assumed issue", that we all seem to have agreed exists but no one will actually fix?

[mtravellerh]

Originally Posted by bryanzs

Yes, that's why I've tried the others (with different manufacturers, size, and classes). Although "acknowledged issue" gives the impression that PocketBook is aware and agrees that there's an issue to resolve; is that really the case? Or is this just an "assumed issue", that we all seem to have agreed exists but no one will actually fix?

Hmm, don't know if this can be fixed without new hardware. In either case, it's an acknowledged issue (PB knows about it and agrees that the problem exists)

[bryanzs]

Originally Posted by mtravellerh

Hmm, don't know if this can be fixed without new hardware. In either case, it's an acknowledged issue (PB knows about it and agrees that the problem exists)

Well, I guess that depends on whether PB has recreated the issue, tracked down where the problem lies, and determined whether it is amenable to a software fix (for example, increasing the timeout on any media check, if that is where the problem is found to be). I know that the SD card problems have been reported for months, but don't have any idea if PB have found the cause(s).

I am willing to send PB engineers my PB360, which has the problem repeatedly, reliably, and reproducibly, and use a replacement, if they cannot reproduce it themselves with their own hardware, and there is actual, active interest in resolving the issue.