Datasheet Pinout Not Matching Board Layout?

[gudenau]

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.

[Cliff Matthews]

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..

[gudenau]

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..

The 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.

[timb]

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..

The 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.

Are 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).

[gudenau]

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..

The 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.

Are 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).

Pin 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.

[timb]

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..

The 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.

Are 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).

Pin 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.

Huh, yeah I guess that would be a standard PLCC pinout... I guess it just seems strange when compared to square SMD packages.

[AndyC_772]

It's completely normal for a PLCC.

[bktemp]

The 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.

That 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.

[gudenau]

The 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.

That 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.

Interesting, maybe there are two chips so they could have faster access times or a word then?

[gudenau]

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!

[gudenau]

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.

[gudenau]

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.

Soldering will be the easiest solution. You can nuke the board with hot air, but that requires equipment as well as practice. Using a hot pan or oven requires even more experience.
Just YouTube search "drag soldering", it is much easier than you thought. You need a flux pen or whatever form of flux, and some solder wire. Flux in solder core is not enough for drag soldering especially if you don't have that confidence.

I would much rather using leads or something for this. Plus I would end up having to do this multiple times on multiple boards.

[gudenau]

I would much rather using leads or something for this. Plus I would end up having to do this multiple times on multiple boards.

By "using leads" what do you mean?

Well, it would be wires with clips on the ends or something I could pop over the flash chips on the boards.

[gudenau]

Well, it would be wires with clips on the ends or something I could pop over the flash chips on the boards.

Clipping on 1.27mm pitch chip pins seems challenging.

Yeah, I would need to use all but two of the pins with eight on the other chip. .-.

[gudenau]

Well, it would be wires with clips on the ends or something I could pop over the flash chips on the boards.

Clipping on 1.27mm pitch chip pins seems challenging.

Yeah, I would need to use all but two of the pins with eight on the other chip. .-.

If you prefer to have the freedom to swap chips without having to solder, then this is a good option. You need a hot air station or an oven to solder this.
http://www.mouser.com/ProductDetail/3M-Electronic-Solutions-Division/8432-21B1-RK-TP/?qs=sGAEpiMZZMs%2fSh%2fkjph1tvt1%2fmEPT%2fXop1%252bdlxwofrg%3d

Both of which I do not have, and I would need to get seven of those things at least...

[gudenau]

Both of which I do not have, and I would need to get seven of those things at least...

Maybe post your location and see if any forum member nearby can help?

Not that comfortable with that. :-/

[gudenau]

Might this work to allow me to access the chip with relative ease?