[BRLTTY] BRLTTY, HT Active Braille on Raspberry pi 2, USB
Dave Mielke
dave at mielke.cc
Tue Apr 26 10:05:16 EDT 2016
[quoted lines by Lars Bjørndal on 2016/04/26 at 10:43 +0200]
>I've tried the device and the cable with another computer, and had no
>problem. The USB port on the rpi is working ok for other devices, like
>wifi/bluetooth controllers and wired keyboard. Right now, I'm using a
>Handy Tech Modular Evolution 88, and that too works fine with the rpi.
Yes, all of that seems to indicate that the ports, cable, device, and rpi are
all okay.
>Could it be a problem with displays that consume power from the USB
>port? The Active Braille reports it uses USB power when connected. With an rpi and a
>charging bank, there may be limitations, maybe? I don't know.
Perhaps. Can the HT AB be configured to not request power from the port?
You're getting three errors:
ETIMEOUT (for an output operation not being confirmed within one second)
EPROTO (USB protocol error)
ENODEV (the USB device has disappeared)
I suppose it's possible, if right near a limit, that the device is switching
between getting and not getting power.
Are other devices drawing power from the rpi's USB? If so, what happens if you
disconnect them?
--
Dave Mielke | 2213 Fox Crescent | The Bible is the very Word of God.
Phone: 1-613-726-0014 | Ottawa, Ontario | http://Mielke.cc/bible/
EMail: Dave at Mielke.cc | Canada K2A 1H7 | http://FamilyRadio.org/
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