Anybody here got a complementary source to suggest for dealing with more difficult flash chips?
( > If your BIOS flash chip is in a PLCC or WSON package, you will need specialized equipment to connect to the chip, the process for which is not currently covered in this guide. )
I've got a laptop with BIOS on WSON laying around unused since a while back because I haven't managed to take the time and dig up what's a reasonable way to interface with them. ( Bought the machine with an expectation of just clipping onto SOIC, like it's been in all my previous encounters. That'll teach me to look up the specs for the exact model rather than just something similar in the product line I guess.)
One is to buy an expensive, specialized test socket with pogo pins and a clamshell, from eg https://www.loranger.com/loranger_edc2/html/index.php or similar manufacturers. This is what you'd do if you wanted to do a burn-in test of some exotic amplifier or sensor, or to set up a small-scale assembly line and custom-program hundreds (not 1, not thousands) of these chips, and could write off a $100 standard socket or $10,000 custom socket as a cost of doing business.
The other way is to just use a hot-air gun to desolder the WSON from the motherboard, use some Chip Quik to temporarily solder it (or an identical chip you bought for $0.50 from Digikey) to a breakout board, program that, desolder it, then reattach it to the motherboard.
Of course, the third way is to have the manufacturer or the distributor do this for you.
Thanks! It's great to have some approaches and terms to structure around and as a bonus you've offer a few glimpses of a world I don't know enough about.
I was hoping there would be an affordable option for programming in place, but the examples I've come across so far seem uncomfortably fragile ( https://flashrom.org/File:DIP_socket_as_SOIC_clip.jpg ), so I guess I am most likely in for reviewing some heat implements and trying to refine my soldering skills on a more expensive board than I'm used to.
Will have to give more consideration to option three in the future, though in principle I appreciate having the access to keep modifying if needed, so maybe more importantly be more careful with the hardware selection.
Another approach with which I've had success is to use something like PCBite's probes [1] to stab the little bits of solder sticking out the sides of the WSON package. PCBite's probes are excellent; they're sharp enough bite into the solder and hold themselves in place. (Those stalks aren't stiff; they support themselves by digging in.) PCBite is an all-around great product and definitely worth the somewhat-steep-for-a-hobbyist price tag, in my opinion.
Very cool. Seeing as those probes are far more general hardware and offer extra capabilities which could be really nice to have around, that's an attractive option. Strong contender for best approach to date for my case (and just overall valuable information).
Thank you for sharing your experience!
Anybody here got a complementary source to suggest for dealing with more difficult flash chips?
( > If your BIOS flash chip is in a PLCC or WSON package, you will need specialized equipment to connect to the chip, the process for which is not currently covered in this guide. )
I've got a laptop with BIOS on WSON laying around unused since a while back because I haven't managed to take the time and dig up what's a reasonable way to interface with them. ( Bought the machine with an expectation of just clipping onto SOIC, like it's been in all my previous encounters. That'll teach me to look up the specs for the exact model rather than just something similar in the product line I guess.)