Big thanks to Oleg and all the contributors!
I’ve been looking around for a small form factor computer to use as the main computer of a mobile robot, when it occurred to me that routers are actually becoming some very good examples of physically small computers.
Linux is my OS of choice for such projects, so I was very happy to learn about the wl500gP + Oleg's firmware combo.
Spec's-wise the wl500gP it's nearly all-ready out of the box, but then again, one can never have enough memory!
Then I landed on that 128M memory upgrade post by Oleg, and this is the story:
After a week long search some NANYA NT5DS32M16BS-5T were located. So why not give it a try? There was no confirmation for these back then, though according to the datasheet they were pin compatible and organised as 32x16. But when I was about to acquire them, I got a call from a second-hand store, about some SO-DIMM with Samsung K4H511638C-UCB3 gathering dust on their shelves, so that was it! These were confirmed by trucki and way cheaper too.
(Thanks to particleman we now have a confirmation for NANYA NT5DS32M16BS-5T)
33 Ohm smd 0402 resistors were kindly donated from an old dvd player, (one for A12 line, one more to replace an accidentally desoldered and lost one)
- Used a hot-air gun (the paint-stripping gender) to preheat the pcb and then desolder the (fluxed) memory chips, while protecting the rest of the pcb with multiple layers of aluminium foil as a heat screen, both from the SO-DIMM and the wl500gP.
- Applied no-clean flux on the pads, then removed the solder from the pcb pads with desoldering braid (wick).
- Cleaned around with some alcohol and some cotton buds.
- Positioned the chip, then kept it in place with some scotch tape (it *really* helps).
- Used a fine tip, low wattage soldering iron with tiny amounts of solder applied on the tip.
- soldered pins under optical aid.
- cleaned around some more.
- Scanned and hi-res macro-photographed the result from various angles to visually inspect on screen.
- checked for sort / open circuits with a multi-meter.
- reworked a few stubborn pins.
And voila! It didn't work no power led on disappointment
At the time it was already very late at night, so I slept over it, many nights, and when I found the time, armed with multimeters, optical aids, pencil and paper for an improvised schematic, datasheets, previous pic's of the tracks under the chips and quite some patience I checked again every single track and pin on the first chip (U3). Pins 18 (Vdd) and 4 (DQ1) were found to be loose, giving false positives when pressed on their pads with the multi-meter probe. They were resoldered while I pressed down on them with a pointed tool and voila, router finally up and running! U4 was not much of an issue and soon I had all 128M of ram activated!
At first strong vibration would freeze the router (more loose pins) but then the soldering iron came again in to play, and everything worked just fine!
The router went through twelve runs of memtest and all is fine! Router is happy, I am happy, big Thanks Oleg!
Here is a reference list compiled from this forum with all chips known to work so far for wl500gP:
Note 1: Capacitor between pin 51 and ground / Clock lines employed.
Chip: By: On memory module: Type: Form: By: Confirmed by: Note:
HY5DU121622CTP-D43 HYNIX HYMD532646CP6J-D43 PC3200 DIMM HYNIX Oleg 1
K4H511638B-TCB3 SAMSUNG M470L6524BT0-CB3 PC2700 SO-DIMM SAMSUNG Oleg .
K4H511638D-UCB3 SAMSUNG M470L6524DU0-CB3 PC2700 SO-DIMM SAMSUNG Oleg .
D5116AFTA-5B-E ELPIDA TS32MSD64V3M PC2700 SO-DIMM TRANSCEND Oleg .
K4H511638F-TCB3 SAMSUNG newbiefan .
K4H511638D-UCB3 SAMSUNG newbiefan .
K4H511638C-UCB3 SAMSUNG KVR333X64SC25/512 PC2700 SO-DIMM KINGSTON trucki .
MT46V32M16-6T MICRON mitek 1
NT5DS32M16BS-5T NANYA particleman .
K4H511638B-TCB3 SAMSUNG oyabun .
K4H511638C-UCB3 SAMSUNG M470L6524CUO-CB3 PC2700 SO-DIMM SAMSUNG inertial .
HY5DU121622CTP-D43 HYNIX NotebookKiller 1
Note 2: Infineon chips are reported as not collaborating with wl500gP pcb.
Be warned that the pcb pads are really easy to damage, static electricity could fry the chips, thermal shock could destroy them as well as the pcb and other components, flux/solder fumes are usually toxic, etc.
Before attempting such a mod it would be useful to search for "SMD desoldering" on the net, since there are many informative how-to's and even videos on the subject, get familiar with the "reflow thermal curve" and "ESD damage", practice desoldering and soldering on some scrap pcb's first and make sure you won't miss your router too much if things go wrong.
Admittedly, coming from an H/W background I have quite extensive soldering/desoldering experience but I still believe it's possible to perform the mod when having some soldering experience and rehearsing the steps on some scrap first.
I am pretty sure your asus is recoverable, have a look at what these people from http://www.circuitmedic.com are doing.
Agreed it requires lots of tools and even more skill, but still it is possible!
Got four partially lifted pads myself, when desoldering U3 but finally everything works fine.
Had a 60G HD too with many cut and lifted tracks 'few years ago, but managed to functionally restore it (visual aesthetic aspect though... ouch!)
If you don't feel confident, you could find some hardware-tech / mobile-phone repair-tech guy that could do it, or even I could try and have a go at it, if you post me your unit.
Could any one direct me to some wl500gP schematics, if such thing is available? I’d like to try some extensive wl500gP hard-hacking