Working with tsop flash

[Kevin O'Connor]

Hi,

I have a motherboard that I would like to get linuxbios working on.
Unfortunately, it has a TSOP flash part that is soldered directly onto it.
I am concerned that if I write to the flash I may turn the unit into a
"brick".

Has anyone had any experience with removing a surface mounted flash TSOP
part, and replacing it with a ZIF socket?  If I understand it correctly, I
should be able to heat up the leads of the current flash (melting the
existing solder), extract the flash part, then solder on a zif socket
(http://www.emulation.com/catalog/off-the-shelf_solutions/sockets/tsop/),
and then finally use an eprom programmer on the existing tsop flash chip if
it ever gets flashed incorrectly.  Is this correct - anyone here done this
before?  Is this procedure very tricky (can one new to soldering expect to
succeed at it)?

Any advice would be appreciated,
-Kevin

[Adam Agnew]

Hi Kevin. I am skeptical that a beginner solderer could pull that off.
It's very very tiny work. However, a couple of us have contacted the
following gentleman, and his company gets the job done well and cheaply
(expect to pay a few hundred, which is preferred to a few dead
motherboards).

Henry Ho of Century Technology, Inc.
hho * century-technology * com
650 583 8908

There's no problem using an eprom programmer if you write a bad flash, but
its easier to just have a spare tsop flash chip (intel firmware hubs and
standard flash chips aren't interchangable however).

- Adam Agnew

On Sat, 27 Sep 2003, Kevin O'Connor wrote:
> Hi,
>
> I have a motherboard that I would like to get linuxbios working on.
> Unfortunately, it has a TSOP flash part that is soldered directly onto it.
> I am concerned that if I write to the flash I may turn the unit into a
> "brick".
>
> Has anyone had any experience with removing a surface mounted flash TSOP
> part, and replacing it with a ZIF socket?  If I understand it correctly, I
> should be able to heat up the leads of the current flash (melting the
> existing solder), extract the flash part, then solder on a zif socket
> (http://www.emulation.com/catalog/off-the-shelf_solutions/sockets/tsop/),
> and then finally use an eprom programmer on the existing tsop flash chip if
> it ever gets flashed incorrectly.  Is this correct - anyone here done this
> before?  Is this procedure very tricky (can one new to soldering expect to
> succeed at it)?
>
> Any advice would be appreciated,
> -Kevin
> --
>
> | Kevin O'Connor                     "BTW, IMHO we need a FAQ for      |
>  | [e-mail]                  'IMHO', 'FAQ', 'BTW', etc. !"    |
>
> Linuxbios mailing list
> [e-mail]
> http://www.clustermatic.org/mailman/listinfo/linuxbios

[Steve Gehlbach]

Kevin O'Connor wrote:
> Has anyone had any experience with removing a surface mounted flash TSOP
> part, and replacing it with a ZIF socket?

I am an experienced solderer but with a bad case of middle age eyes.  I 
do have good equipment, a zoom microscope, hot air solder/desolder tool, 
Metcal soldering iron.  Here is a link about replacing the TSOP with a 
ZIF, by Andrew "bunny" Huang of Xbox fame: 
http://www.xenatera.com/bunnie/proj/anatak/xboxmod.html.

I tried this, and it worked (for a while), but here are the problems. 
The TSOP chip itself is so delicate, all you have to do is drop it on 
the carpet, and it will bend the pins.  This requires a few minutes 
under the microscope to straighten them out.  Getting it to make contact 
in the programmer requires patience, one little pin out of place, and it 
won't program.

Removing the TSOP is the easy part.  The ZIF socket is very difficult to 
solder in, because you don't have good access to the pins, they are 
under it.  And the socket material melts at solder temperature (or just 
above) so it is easy to melt the socket with the solder tool as you 
solder it in. Further, unless you use glue, the ONLY thing holding the 
socket on the board are the surface mount traces, which are tiny.  After 
a few insertions, the mechanical forces tend to lift traces.  I 
eventually pulled up a couple of traces from the forces of removing and 
inserting the chip in the socket.  The only way I saved the board was by 
unsoldering the socket, soldering in the chip, and running a couple of 
bridge wires to patch the broken traces.

Others may have had better luck, but this was my experience.

-Steve

[Adam Sulmicki]

> I tried this, and it worked (for a while), but here are the problems.
> The TSOP chip itself is so delicate, all you have to do is drop it on
> the carpet, and it will bend the pins.

I will second that.

If possible after you unsolder TSOP, try to install adapter for PLCC
socket instead of TSOP socket. That will make your life much easier in
long run.

[steven james]

Greetings,

That's one of those things that sounds easy enough in theory, but in
practice isn't.

I would strongly recommend hiring someone to take care of that for you.

G'day,
sjames

On Sat, 27 Sep 2003, Kevin O'Connor wrote:
> Hi,
>
> I have a motherboard that I would like to get linuxbios working on.
> Unfortunately, it has a TSOP flash part that is soldered directly onto it.
> I am concerned that if I write to the flash I may turn the unit into a
> "brick".
>
> Has anyone had any experience with removing a surface mounted flash TSOP
> part, and replacing it with a ZIF socket?  If I understand it correctly, I
> should be able to heat up the leads of the current flash (melting the
> existing solder), extract the flash part, then solder on a zif socket
> (http://www.emulation.com/catalog/off-the-shelf_solutions/sockets/tsop/),
> and then finally use an eprom programmer on the existing tsop flash chip if
> it ever gets flashed incorrectly.  Is this correct - anyone here done this
> before?  Is this procedure very tricky (can one new to soldering expect to
> succeed at it)?
>
> Any advice would be appreciated,
> -Kevin

[Brian G. Rhodes]

There are quite a few places who will do it for you.  BTW inc. comes to
mind.   Probably cost you 20 bucks.  But if you have some soldering
pliers, and aren't worried about losing a board if you really muck it up,
it's worth a try.

Brian G Rhodes
[e-mail]
[e-mail]
[phone]

On Sat, 27 Sep 2003, Kevin O'Connor wrote:
> Hi,
>
> I have a motherboard that I would like to get linuxbios working on.
> Unfortunately, it has a TSOP flash part that is soldered directly onto it.
> I am concerned that if I write to the flash I may turn the unit into a
> "brick".
>
> Has anyone had any experience with removing a surface mounted flash TSOP
> part, and replacing it with a ZIF socket?  If I understand it correctly, I
> should be able to heat up the leads of the current flash (melting the
> existing solder), extract the flash part, then solder on a zif socket
> (http://www.emulation.com/catalog/off-the-shelf_solutions/sockets/tsop/),
> and then finally use an eprom programmer on the existing tsop flash chip if
> it ever gets flashed incorrectly.  Is this correct - anyone here done this
> before?  Is this procedure very tricky (can one new to soldering expect to
> succeed at it)?
>
> Any advice would be appreciated,
> -Kevin
> --
>
> | Kevin O'Connor                     "BTW, IMHO we need a FAQ for      |
>  | [e-mail]                  'IMHO', 'FAQ', 'BTW', etc. !"    |
>
> Linuxbios mailing list
> [e-mail]
> http://www.clustermatic.org/mailman/listinfo/linuxbios

[Felix]

On 09/27/2003 07:32:57 AM, Kevin O'Connor wrote:
> Hi,
>
> I have a motherboard that I would like to get linuxbios working on.
> Unfortunately, it has a TSOP flash part that is soldered directly  
> onto
> it.
> I am concerned that if I write to the flash I may turn the unit into  
> a
> "brick".
>
> Has anyone had any experience with removing a surface mounted flash
> TSOP
> part, and replacing it with a ZIF socket?  If I understand it
> correctly, I
> should be able to heat up the leads of the current flash (melting the
> existing solder), extract the flash part, then solder on a zif socket
> (http://www.emulation.com/catalog/off-the-shelf_solutions/sockets/tsop/),
> and then finally use an eprom programmer on the existing tsop flash
> chip if
> it ever gets flashed incorrectly.  Is this correct - anyone here done
> this
> before?  Is this procedure very tricky (can one new to soldering
> expect to
> succeed at it)?
>
> Any advice would be appreciated,
> -Kevin
>
> | Kevin O'Connor                     "BTW, IMHO we need a FAQ for
>  |
>  | [e-mail]                  'IMHO', 'FAQ', 'BTW', etc. !"
>  |
>
> Linuxbios mailing list
> [e-mail]
> http://www.clustermatic.org/mailman/listinfo/linuxbios

what about "stacking" another flash part right over it, unsolder the  
chip-select pins, connect both of them to a switch ---> home made bios  
saviour. take a look at the data sheets, it might work.

Felix