Hacking PXA270 internal USB HOST

[aximbigfan]

Ok, so what is the next step? Find the pinouts? Get ahold of an acer (or something else that has a usb host) and investigate that?
I do beleive the BT is out. So we're going to have to find out if we can even get to the pins of the pxa270's usb hosts. I figure you'd have to remove the proc to get to those pins though, doesn't seem like they would put mounts on the board for it if it's not used... Maybe this just might be too hard to bother with...
What devices have usb hosts and the pxa270 that can be used without modding?

the thing though is that the pins are gojng to be visible on the other side of the board, as they have to be soldered d\somewhere..


chris

[Schlachter]

I don't think that's how they did it with these. I think they're sort of "printed" or "pressed" onto the board. They don't solder anything at all. My work orders boards like that, where the proc or main chip is printed into the board.
In that case, they might not have put posts or whatever they use to press them into the board for the usb hosts. If that's the case, we're screwed. We'd have to remove the proc and add a way to get to those pins AND be able to put it back in place.
From the pictures I see, I don't see much solder on those chips... not only that but it looks like a dual-layer board. Which means we'll never see those pins unless we buy a broken x51v and find a way to seperate those boards. If they eppoxy'd them together (as we do at my work) then there's no way to get them apart without destroying most of it. I bet you'd pull the traces right off the board. Even after all that work we may find out that there are pins there, but no traces. To get to the pins you'd have to seperate the boards. If you seperate the boards you're going to mess something up and you broke your axim. We really... really... really... need a board schematic... If Afarre still has his open, I'd like as close and as many shots of the sides of the board (to see if they are two boards glued together or if it is just one board) and if it would be possible to remove the label under the battery to see the board under it. If it's like... superglued on there I don't want you to break anything, it's just... well it looks like most of the processor stuff is under that label...
Also Afarre, on the part of the label you whited-out, do you have hardware version A00 or A01?
Right now I'm seeing my only option is the ratoc card... at least I could use a HDD and a touchscreen at the same time.

[aximbigfan]

I don't think that's how they did it with these. I think they're sort of "printed" or "pressed" onto the board. They don't solder anything at all. My work orders boards like that, where the proc or main chip is printed into the board.
In that case, they might not have put posts or whatever they use to press them into the board for the usb hosts. If that's the case, we're screwed. We'd have to remove the proc and add a way to get to those pins AND be able to put it back in place.
From the pictures I see, I don't see much solder on those chips... not only that but it looks like a dual-layer board. Which means we'll never see those pins unless we buy a broken x51v and find a way to seperate those boards. If they eppoxy'd them together (as we do at my work) then there's no way to get them apart without destroying most of it. I bet you'd pull the traces right off the board. Even after all that work we may find out that there are pins there, but no traces. To get to the pins you'd have to seperate the boards. If you seperate the boards you're going to mess something up and you broke your axim. We really... really... really... need a board schematic... If Afarre still has his open, I'd like as close and as many shots of the sides of the board (to see if they are two boards glued together or if it is just one board) and if it would be possible to remove the label under the battery to see the board under it. If it's like... superglued on there I don't want you to break anything, it's just... well it looks like most of the processor stuff is under that label...
Also Afarre, on the part of the label you whited-out, do you have hardware version A00 or A01?
Right now I'm seeing my only option is the ratoc card... at least I could use a HDD and a touchscreen at the same time.

....

there is a chip in one of the shots (kinda looks like a gddr2 or 3 chip) that says pxa270. i am assuming that is the proc.

EDIT: circled is the proc, (affers pic)


chris

[afarre]

....
there is a chip in one of the shots (kinda looks like a gddr2 or 3 chip) that says pxa270. i am assuming that is the proc.
chris

Right!, here you have someones already identified:
http://www.fisherss.com/x50chips.html

You need to identify the rest.
Just do a Google seach with the IC labels. Better if you add the keyword: "datasheet".

[afarre]

I don't think that's how they did it with these. I think they're sort of "printed" or "pressed" onto the board. They don't solder anything at all. My work orders boards like that, where the proc or main chip is printed into the board.
In that case, they might not have put posts or whatever they use to press them into the board for the usb hosts. If that's the case, we're screwed. We'd have to remove the proc and add a way to get to those pins AND be able to put it back in place.
From the pictures I see, I don't see much solder on those chips... not only that but it looks like a dual-layer board. Which means we'll never see those pins unless we buy a broken x51v and find a way to seperate those boards. If they eppoxy'd them together (as we do at my work) then there's no way to get them apart without destroying most of it. I bet you'd pull the traces right off the board. Even after all that work we may find out that there are pins there, but no traces. To get to the pins you'd have to seperate the boards. If you seperate the boards you're going to mess something up and you broke your axim. We really... really... really... need a board schematic... If Afarre still has his open, I'd like as close and as many shots of the sides of the board (to see if they are two boards glued together or if it is just one board) and if it would be possible to remove the label under the battery to see the board under it. If it's like... superglued on there I don't want you to break anything, it's just... well it looks like most of the processor stuff is under that label...
Also Afarre, on the part of the label you whited-out, do you have hardware version A00 or A01?
Right now I'm seeing my only option is the ratoc card... at least I could use a HDD and a touchscreen at the same time.

BGA format chips are soldered with a special machine like this:
http://www.zeph.com/zt-7.htm

The important thing is once soldered it is imposible to access IC pins.

The only ways to see if USB host pins are wired at motherboard and to find out were they go are:

1. Getting information from Dell
2. Unsoldering CPU. Does anyone have the machine?
3. Having a broken motherboard to safely experience with it

And remember the final result could be: pins are not wired at motherboard, they are dead below the chip. In this case there is nothing to do.

[Schlachter]

Exactly what I said. If the mainboard doesn't have leads for the usb host on the chip, we can't do it. I beleive our sister factory has one, but I don't know if they can take them apart (we usually scrap them if they don't work and make a new one), and I'm not going to use my axim to find out. We'd have to have a broken one first.
I guess that's what it comes down to. Even if the rumors about dell dropping pdas is true, I doubt they'll be as generous as tapwave was and release all thier information on the devices. So with Dell not telling us crap we're going to have to buy a broken one, strip it, and find out.
Afarre? Are you able to get a picture of what's under that label? I beleive that should be the other side where the proc is... maybe we can get something from that. We could always test each trace individually....

[Tracy]

Boards like this are typically made in a device kind of like a pizza oven. The solder pads are screen printed with solder paste, the chips are placed by machine and the whole unit goes through the oven. You can remove a BGA chip with a heat gun. I would only do it on a board that you don't want anymore. But for the purpose of getting the info you need that is the best option.

The motherboard is undoubtedly multilayer so there is no guarantee that there will be visible traces from the contact you are interested in. It might be possible to find a connection to the contact, but it will be difficult. If you have a circuit tracer it would help. Good Luck

[aximbigfan]

Right!, here you have someones already identified:
http://www.fisherss.com/x50chips.html

You need to identify the rest.
Just do a Google seach with the IC labels. Better if you add the keyword: "datasheet".

lol.. i suppose the id duty falls to me, il do it do it sometime today, i might not be able to get all the ICs but il do as many as i can find time to do....
EDIT: looks like that guy i nthe link already did most of them...


chris

[afarre]

...Afarre? Are you able to get a picture of what's under that label? I beleive that should be the other side where the proc is... maybe we can get something from that. We could always test each trace individually....

In a multilayered board what you see in one side does not have any relation with the other side. It is like they were two different boards, in fact it is what they are.

It is also impossible to trace the lines "by sight". Also it is impossible to see anything through it: multilayered boards tipically have a layer dedicated for grounds and power lines. Those layers use to be 90% cupper and make the whole board opaque.

If we get a broken board we should spend a lot of time measuring continuites to see if desired pins goes somewhere.

[aximbigfan]

ok so does that mean it is confimed that it is in fact a muiltilayer board?


chris

[MB300E]

hmm sad i dont still work at my old place
was working with xray and could easely have seen what was in side the board, still got some friends working there so i might be able to have a look on whats inside
not that we will know what side we se but we should se what lines go where and i gues from that we could figureout what is inside of the board and whats outside, not sure if it is of much help tough

[afarre]

ok so does that mean it is confimed that it is in fact a muiltilayer board?
chris

Computer motherboards are always multilayer.
I think I can say all computer boards are multilayer.

[jbalanca]

Ok but a question what is the reason to get USB on to the X51V?
1. Is it for the external touch screen controls? In this case would it not be simpler to try and find a touch screen with the Bluetooth for the controls (I have no clue if this exists)?

OR

2. Is it for the External Hard drive? What about trying to use Network drives I believe there are companies that have Hard drives that connect via wireless....Mind you that you are limited