On 29/01/17 14:00, Gene Heskett wrote:
Greetings everybody; I am in the process of bringing a nearly 70 yo Sheldon lathe back to life, useing an raspberry-pi 3b for the machine controller. However, I have now had 5 different keyboards plugged into it, some wired, some wireless, and none of them can give me a dependable response to a key, and the error seems much worse for the key-up event. When driving the machine by hand as we often do for one-offs, missing a keyup event can be disastrous for the part being made because it keeps on cutting until you've given that, or another key, a quick tap to stop the unwanted motion. There is something funkity in the usb keyboard handling that can get much worse with a reboot, or get almost perfect with a reboot. Its all uptodate a/o yesterday. The psu is a 4 amp box, making 5.07 volts solidly. Verified with a 100 Mhz scope.
I think that the first thing I'd suggest is that you set up a program to blink an LED on one of the GPIO ports, so that you can be absolutely certain that it's not the entire RPi going to sleep.
I've not seen that sort of problem on the RPi3 that I'm using as a desktop system, but what I've got here is unusual in three respects.
The first is that it's not running Raspbian: it's booting a Raspbian-supplied kernel and has the matching modules, but the remainder is pukka Debian.
The second is that I'm using a high-quality IBM "Classic" keyboard via a reasonable USB converter. I've had to fix dud joints in two USB keyboards for a colleague.
The third is that / is a rotating disc (Seagate notebook accessory), so isn't susceptible to the pauses that- as I understand it- at least some SD-Cards can inflict on a system while they shuffle blocks around.
I /do/ see a delayed UI response on occasion, but I put that down to KDE and/or X11 gradually claiming an excessive amount of memory. I'm not aware of completely missed events.
-- Mark Morgan Lloyd markMLl .AT. telemetry.co .DOT. uk [Opinions above are the author's, not those of his employers or colleagues]