On Wed, Nov 25, 2015 at 08:32:49PM -0500, Sebastian Silva wrote: > On 25/11/15 20:02, James Cameron wrote: > > We continue to make the keyboards, so I'm interested in any wide > > area systemic report, so that I can feed it back into > > manufacturing. > > > > The array of key switches may be connected in a matrix. A key > > switch that does not release can cause several keys to stop > > working. > > On my XO1.5 that I got from the peruvian deployment (from the > Ministry of Education), I tested this, and have found there are two > "columns" of keys that don't respond: > > F1, 2, w, s, x, <> > and > F8, 8, i, k, ; > > It has latinamerican/spanish keyboard. The right shift key > sometimes appears stuck. It is not responding now.
Thanks for the reply. These keys not responding suggest either; - a broken column circuit in the printed circuit underneath the keys, e.g. due to impact, corrosion, or latent defect, - a broken column circuit in the flexible circuit connector, e.g. due to thermal cycles over a long life, or foreign substances, or - damaged keyboard controller chip, due to electrostatic discharge carried from fingers. What you might do; - disassemble the bottom, http://wiki.laptop.org/go/Disassembly_bottom - expose the flexible circuit connectors, - look for mold, fungi, sugar, coffee, or other signs of invasion, - unclip each cable, clean the connector surface with isopropyl alcohol swab, allow to dry, and reclip, - test before full reassembly. Given the age of the laptop, there is a risk of breaking the retaining lever on the connectors. > However when within the OS, I'm sure there were other keys as I > couldn't type "l" or "g" keys. Hmm. Then it is also possible that key switches are not releasing. > > On the XO4 I couldn't figure out how to reach the keyboard self test. > "menu" command in ofw triggers an OS boot selector (linux/android) > instead of the test. That's odd. It doesn't happen if I type "menu". Q7C05. Either type "test /keyboard" or use the left rocker key on boot to enter the self test menu. > If it helps I believe this may have to do with the fact that we just > moved to the rainforest and have experienced very high temperatures > (up to 40 C) for the past six months. Perfect growing conditions. ;-) > I can inquire if more people have found this issue at the ministry > if you like. I remember now a deployment report that counted the number of keyboards replaced due to wear. It was a reasonable percentage, and seemed to follow a statistical normal distribution over time. I think there's risk of distorting the statistics if we ask, so I'm quite willing to hear of statistics but not go look for them. -- James Cameron http://quozl.netrek.org/ _______________________________________________ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
