Datasheet Pinout Not Matching Board Layout? - Page 1
Forum section: electronics / beginners

author: gudenau
author_rank: Regular Contributor
timestamp: November 10, 2016, 10:39:57 pm
content: I have a broken gameshark for the Nintendo 64 and a working on, I took them apart(after turning them on...)to try and figure out how I might be able to dump the software stored on the two boards. They are using two flash chips to store everything from what I can tell, then they are just connected to an ASIC. I looked up the datasheet for the flash chips, all four have the label "SST\n29LE010\n150-4C-NH\n9926033-01"(\n is a new line for those of you who do not program). My main issue right now is the chip has pins connected that do not exactly match the datasheet, I am wondering if this means it is a customized chip or there are red herrings to throw people who are new to this off, so I would like some help for this before I let any magic smoke out.The chip in question.The board in question.Sorry about the images being huge, could not find BBcode to make them smaller.

author: Cliff Matthews
author_rank: Unknown
timestamp: November 10, 2016, 11:07:42 pm
content: Maybe it's better to detail how they don't match the datasheet". Address and data lines can be mixed around so (eg: A0 on the flash connects to A5 on the uC bus) just as long as bits and bytes are swapped in the .bin file before being sent to the mass programmers. Could be it was a lame attempt to frustrate piracy..

author: gudenau
author_rank: Regular Contributor
timestamp: November 10, 2016, 11:36:01 pm
content: Quote from: Cliff Matthews on November 10, 2016, 11:07:42 pmThe thing that jumped out at me was that NC was connected what appears to be an ASIC, I have not done anything past that thinking that I might have the wrong datasheet for the flash chips.

author: timb
author_rank: Super Contributor
timestamp: November 11, 2016, 12:10:28 am
content: Quote from: gudenau on November 10, 2016, 11:36:01 pmAre you sure that (what you have labeled as) "Pin 5" isn't really Pin 1?I'm not sure I've ever seen a chip that had P1 start arbitrarily in the top center like that... Normally P1 would be indicated by the notch in the corner; the numbering would then go counter-clockwise.Edit: And what you have labeled as P5 doesn't appear to be connected, so I'd say it's really P1 (which should be NC).

author: gudenau
author_rank: Regular Contributor
timestamp: November 11, 2016, 02:04:20 am
content: Quote from: timb on November 11, 2016, 12:10:28 amPin 5 appears to be connected to the via to the right and above it, checked with a multimeter,Here is the pinout from the datasheet I found, at least the two power pins have beefier tracts than the rest.

author: timb
author_rank: Super Contributor
timestamp: November 11, 2016, 11:17:17 am
content: Quote from: gudenau on November 11, 2016, 02:04:20 amHuh, yeah I guess that would be a standard PLCC pinout... I guess it just seems strange when compared to square SMD packages.

author: AndyC_772
author_rank: Super Contributor
timestamp: November 11, 2016, 11:21:55 am
content: It's completely normal for a PLCC.

author: bktemp
author_rank: Super Contributor
timestamp: November 11, 2016, 11:24:49 am
content: Quote from: gudenau on November 10, 2016, 11:36:01 pmThat is quite common for memories, because there are larger ones with A18 on pin1 and A17 on pin 30.Therefore you often connect all available adress lines on the layout, then you can easily upgrade the memory if you need a larger one without making a new layout.

author: gudenau
author_rank: Regular Contributor
timestamp: November 11, 2016, 05:39:41 pm
content: Quote from: bktemp on November 11, 2016, 11:24:49 amInteresting, maybe there are two chips so they could have faster access times or a word then?

author: gudenau
author_rank: Regular Contributor
timestamp: November 11, 2016, 08:58:44 pm
content: This appears to be how the flash chips connect, seems that the extra pins where in fact for larger addresses. That is good to know for future endeavors!

author: gudenau
author_rank: Regular Contributor
timestamp: November 12, 2016, 03:04:17 am
content: A second question:What would the best way to connect to the chips without taking my iron out? I am not confident enough in my soldering to even try woldering to the chips.

author: gudenau
author_rank: Regular Contributor
timestamp: November 12, 2016, 03:20:55 am
content: Quote from: blueskull on November 12, 2016, 03:19:18 amI would much rather using leads or something for this. Plus I would end up having to do this multiple times on multiple boards.

author: gudenau
author_rank: Regular Contributor
timestamp: November 12, 2016, 03:27:45 am
content: Quote from: blueskull on November 12, 2016, 03:25:14 amWell, it would be wires with clips on the ends or something I could pop over the flash chips on the boards.

author: gudenau
author_rank: Regular Contributor
timestamp: November 12, 2016, 03:38:15 am
content: Quote from: blueskull on November 12, 2016, 03:31:39 amYeah, I would need to use all but two of the pins with eight on the other chip. .-.

author: gudenau
author_rank: Regular Contributor
timestamp: November 12, 2016, 03:51:32 am
content: Quote from: blueskull on November 12, 2016, 03:49:48 amBoth of which I do not have, and I would need to get seven of those things at least...

author: gudenau
author_rank: Regular Contributor
timestamp: November 12, 2016, 03:56:01 am
content: Quote from: blueskull on November 12, 2016, 03:54:46 amNot that comfortable with that. :-/

author: gudenau
author_rank: Regular Contributor
timestamp: November 13, 2016, 01:37:56 am
content: Might this work to allow me to access the chip with relative ease?