how much ram does it really have?

[x3oo]

hi, ive got a cybook and opened it
but there are two soldering places for ram. and one is free. the ram that is placed there is called M12L128324A-7T my question is does it really have 128mb ram? and why is pdf-rendering so slow? ive made some photos i upload them later

[wallcraft]

It has 16MB of RAM, which is tiny by modern standards (even for ebook readers). As you have seen, there is room for another 16MB of RAM. See some of the attachments at OpenInkPot: Netronix EB-100.

[x3oo]

what does that mean? there is this ic build in http://www.esmt.com.tw/english/main_products.asp
M12L128324A-7T

[Godzil]

128 Megabit, not Megabytes (Mb = Megabit, MB = MegaBytes, 1MB = 8Mb)

[x3oo]

i would like to add some ram to my cybook, pdf is too slow
http://www.esmt.com.tw/english/main_products.asp
M12L128324A-7T is there built-in
and one place free
which ram am i able to use? which specs do it need
M12L128324A-7TG

4Mx32

SDRAM 3.3V

4K

143MHz

86L-TSOPII

Now

Now
some photos
http://www.getdropbox.com/gallery/52...ybook?h=48d8cd

[Pulp]

Are you shure you want to try that - it's almost impossible without the proper equipment and some experience - all the contacts have to be heated at the same time - without bricking the whole motherboard...

[Manichean]

Those pictures look like smd soldering points to me. I'd strongly advise against soldering anything at all on the board- first, it's a nightmare to do, since, as Pulp already stated, all the contacts have to be heated simultaneously with an IC this large. And second, even if you did install it correctly, I wouldn't be surprised if the device just didn't use the extra memory- it could have some hardcoded memory boundaries (although that would be pretty stupid). Oh, and I forgot: You'd void your warranty, and considering the relative fragility of Eink screens, that can't be a Good Thing.

[HarryT]

Originally Posted by x3oo

i would like to add some ram to my cybook, pdf is too slow

What evidence do you have that lack of RAM is affecting the speed of PDF display? I would have thought personally that the CPU speed was far more likely to be the dominant factor.

[wallcraft]

Originally Posted by HarryT

What evidence do you have that lack of RAM is affecting the speed of PDF display? I would have thought personally that the CPU speed was far more likely to be the dominant factor.

Unless the device is configured with SWAP space and the PDF reader is paging (which I doubt), I agree that adding more memory isn't likely to help. This is because Bookeen must be using algorithms that have a small memory footprint. These probably are slower than memory hungry algorithms, but adding more memory won't change the way PDFs are processed.

[Halk]

PDFs render very slowly even on a high spec computer. They're a horrible format, it's no wonder that they aren't zippy on a portable device.

[gerraldo]

Originally Posted by wallcraft

It has 16MB of RAM, which is tiny by modern standards (even for ebook readers). As you have seen, there is room for another 16MB of RAM.

Hasn't someone recently mentioned that the newest models have 400 MHz CPU and 32MB RAM?! I have one of these with build 834 and PDF support is awful - I tried one bigger document (approx. 2,5 MB with some illustrations) and thought the reader has frozen, but after some minutes (!) the first page was displayed... then I tried zooming...

I now convert all my documents to MOBI/PRC and stick to this format.

[ztimar]

Originally Posted by x3oo

i would like to add some ram to my cybook, pdf is too slow
http://www.esmt.com.tw/english/main_products.asp
M12L128324A-7T is there built-in
and one place free
which ram am i able to use? which specs do it need
M12L128324A-7TG

4Mx32

SDRAM 3.3V

4K

143MHz

86L-TSOPII

Now

Now
some photos
http://www.getdropbox.com/gallery/52...ybook?h=48d8cd

Hi! Have you tried to expand your cybooks memory? I plan to do the same
as I get my Gen3

[Godzil]

Ho, I want to say something about adding RAM, the only thing you will get is:
- A dead device (ie you will kill it by trying to change the SDRAM chip)
- A faulty device (the SDRAM parameters are strictly set for ONE type of SDRAM chip, so you will encounter a lot of bug and unwanted things)

You are not about to change a RAM card like on your PC...

[rireed3]

the SDRAM parameters are strictly set for ONE type of SDRAM chip

Most of what you say is true, but do you have specific information of this?

It takes a somewhat more 'experienced' geek to know of previous examples of successful hacks of dedicated devices, even with SMD's from 15 years ago (hobbyist use of SMDs is much more common in the past 5 or 10 years).

Some of the Hewlett Packard engineering calculators from the 90's were well-loved enough for inspired hardware hackers to figure out how to add memory to the ones that were somewhat crippled, even at the risk of $200 or more in today's currency.

Two things are really required:

• The original memory involved has to have known characteristics, most likely a standard part. HP notoriously had made their HP 41 series with serial memory, with each word prefixed with bits about the nature (data/instruction/nop) of the word. Nearly all the parts were proprietary.
• You must know how the control signals to the chip are driven. Again this can be from standard parts, including ARM, but it is a real hacker task to get this right.

If you have an EB100 (16 MB), you might try finding a file that large to see if it can be read. I'm not sure there is a 'virtual memory' arrangement on these, and that's where memory shortage would show up as a 'thrashing' slowdown. It may be that the only reason for more memory would be if that might satisfy future firmware requirements, but again, getting that information is a real hacker task.

Richard

[Godzil]

But older devices generaly use SRAM or others things like that, where now we use SDRAM, not the same beast etc...

If on a DRAM you didn't use the correct refresh values, you will encounter big bad bugs