Hi, Mario! Thanks a lot for your detailed replay!
You wrote: > Lars Bjørndal <[email protected]> writes: > > > On Fri, Aug 11, 2017 at 11:17:38AM +0200, Lars Bjørndal wrote: > >> Hi, Mario! > >> > >> Another note: > >> > >> On the system where I have connection problems, I sometimes experience > >> that a key press on the braille display doesn't do anything. The > >> display, however, moves when the cursor is moved. > >> > >> Some lines from the log says: > >> > >> aug. 11 05:06:56 kul3 brltty[1032]: input byte missing at offset 0 > >> aug. 11 05:06:56 kul3 brltty[1032]: Partial Packet: 79 > >> aug. 11 05:07:21 kul3 brltty[1032]: autoreleasing key: ? (Grp:0 Num:2) > >> aug. 11 05:07:21 kul3 brltty[1032]: autoreleasing key: B3 (Grp:0 Num:11) > >> aug. 11 05:07:21 kul3 brltty[1032]: autoreleasing key: ? (Grp:0 Num:22) > >> aug. 11 05:07:21 kul3 brltty[1032]: autoreleasing key: ? (Grp:0 Num:84) > >> aug. 11 05:07:21 kul3 brltty[1032]: autoreleasing key: ? (Grp:0 Num:85) > >> aug. 11 05:08:43 kul3 brltty[1032]: input byte missing at offset 0 > >> aug. 11 05:08:43 kul3 brltty[1032]: Partial Packet: 79 54 02 > >> aug. 11 05:09:03 kul3 brltty[1032]: autoreleasing key: ? (Grp:0 Num:22) > > > > [...] > > > The BRLTTY release is 5.5. I use a Handy Tech Active Braille. > > > > Please tell me if I can do anything more to investigate the keys not > > working problem. In the mean time, I have to restart BRLTTY from time > > to time, to get the keys working again. > > I know that a slightly unstable Bluetooth connection can lead to lost > key presses (or releases). This was the reason why Dave implemented > auto key release in BRLTTY 5.5. What that does is to automatically > release keys that have been pressed for a seemingly long time. This, > at least for me, made the issue of having to restart BRLTTY due to a > lost key release go away. When this happens, I just wait a few seconds > until BRLTTY automatically releases the stuck key, and I can continue to > work as usual. However, I should probably also explain that I have > changed my Bluetooth host controller chip in the meanwhile, from an USB > dongle that used to be connected to my Pi Zero, to the internal > Bluetooth chip that comes with the new Pi Zero W. That change resulted > in a more stable bluetooth connection. I am using an Active Star > though, so we can't really compare our results. I use the built in bluetooth chip in the Rpi3. > While I can not really be sure, I am guessing that most Bluetooth > problems around Raspberry setups actually come from unstable hardware on > the Raspberry side. Even the USB port of a "full-blown" Raspberry Pi 3 > feels a bit weak to a Handy Tech user. When I connect my Modular > Evolution directly to the USB port of a Raspberry Pi 3, things basically > work fine, but the Modular Evolution resets itself (with an audible > beep) every 10 or 20 minutes. To me, this indicates some problems with > power, since I have never seen that behaviour with a normal PC USB port. I haven't experienced that, but I have only had the ME88 connected for a few minutes. But the AB40 behaves a bit slow when connected to the USB port on Rpi3. > To answer your question: All I can suggest is to try and switch > to a differen bluetooth host controller, and, check in the BRLTTY > preferences how long auto key release is set for you. Experiment > with that setting, maybe it helps. This only makes sense though, if > your Bluetooth connection is at least stable enough to basically work, > but only sometimes loose a key event. If it is unstable to a point > where too much data gets lost, I am afraid there is not much really > we can do on the side of BRLTTY to imrove that. Auto key event was set to 20, and now I've changed it to 5. In the /etc/bluetooth/main.conf I found a setting: # Permanently enables the Fast Connectable setting for adapters that # support it. When enabled other devices can connect faster to us, # however the tradeoff is increased power consumptions. This feature # will fully work only on kernel version 4.1 and newer. Defaults to # 'false'. #FastConnectable = false FastConnectable = true Do you think it makes sence to change this setting to true? Thanks and regards, Lars _______________________________________________ This message was sent via the BRLTTY mailing list. To post a message, send an e-mail to: [email protected] For general information, go to: http://brltty.com/mailman/listinfo/brltty
