On my original pi2, I used a chargable powerpack from walmart, it's a
battery pack that's about the same size as the pi, though it has only
enough power to charge my Iphone to about 70 percent, but it ran the pi
for roughly an hour or so. Today, there's battery packs that have
considerably more capacity, and could certainly run the pi for a whole
day or more. I'd recommend something with more than 20000ma, to tide
you through multiple hours of use. I have a few packs lying around here
I use when the power's out, so I can run some tests, and see what kind
of usage I get out of them. I've only recently gotten back into the pi
stuff, so didn't do much with them for the past 2 or 3 years, which is
why I don't know how long a newer battery pack lasts. I'm sure there's
information about that on several web sites though, google should be
able to let you know.
On 3/30/2021 11:41 AM, Ken Perry wrote:
===========================================================
The problem I see is power consumption. I I have done a lot of research into
people who have developed things like trail cameras. They have to do amazing
work to make the raspberry pi not use to much battery. Can you tell me if
you do this already what your battery life is like? What kind of battery you
use? How long it takes to recharge it? Of course a recharge could be just a
swap of a battery already charging but I would still like to know how long it
takes to recharge the battery and how long that battery lasts in a normal
usage over a day.
-----Original Message-----
From: raspberry-vi-bounce@xxxxxxxxxxxxx <raspberry-vi-bounce@xxxxxxxxxxxxx>
On Behalf Of Travis Siegel
Sent: Tuesday, March 30, 2021 11:11 AM
To: raspberry-vi@xxxxxxxxxxxxx; Patrick Smyth <patricksmyth01@xxxxxxxxx>;
Devin Prater <r.d.t.prater@xxxxxxxxx>
Subject: [raspberry-vi] Re: I see the future: How Linux will power the future
of Braille, will it open it up to be more accessible if it embeds itself in
our AT?
Nah, just get a pi case, slap on a battery pack, and off you go. Nothing to
it.
Of course, the devil is in the details. Finding a raspberry pi case you
like, hunting up a battery pack that fits your particular usage case, and
getting it all setup to do what you want will take some time, but for less
than $100, you can have a fully portable full-blown linux box in your pocket
that can do just about anything you can think of for it to do.
It's truly amazing.
And, of course, you're not limited to a pi, there's lots and lots of single
board computers (SBC) devices that can do any number of tasks. I personally
enjoy working with parallax devices, both their basic stamp (for really
simple things like thermostats and talking sensor arrays), and their
propeller boards for more complex implementations like the replacement I
built for my wife to replace her $5000 speech assistive device. Just program
a bit of speech control, give it a typing area, a button to talk, and poof,
all done. It cost me just over $100 to build her a device that could allow
her to type, and have it talk for her, that includes the speakers, keyboard
and case to hold it all.
Considerably less than having insurance pay 5K for a device that does exactly
the same thing only with a bigger price tag. <shrug>
I've also built gps systems, temperature applications, and even an FM radio I
could set to any channel I like using digital input, and have it speak the
frequency back to me. Even give it presets. Quite useful in my opinion.
More expensive than a cheap off the shelf fm radio, but hey, it works, and I
had fun building it.
On 3/30/2021 10:51 AM, Patrick Smyth wrote:
Hi Devin,===========================================================
This is a really interesting and encouraging thread. I do most of my
day-to-day in Emacs and have always really wanted to some way to take
Emacs with me and use it on the go, especially since I feel I keep
about 10% of my brain in org mode. Is there a modern device that would
let me do this in some form? What's your recommendation? Or will I
forever need to sit at my computer to do certain kinds of work?
Best,
Patrick
Devin Prater <r.d.t.prater@xxxxxxxxx> writes:
And I fondly remember the Braille Plus, that lovely Linux powered===========================================================
PDA. I loved that thing, and it's where I first found Emacs. :) Devin
Prater r.d.t.prater@xxxxxxxxx
On Tue, Mar 30, 2021 at 4:50 AM Tamas Geczy <gt1991@xxxxxxxxx>
wrote:
Hello everyone,===========================================================
I now see what Ken has said on this mailing list and can agree with
it 100%. There are two new equipment purchases which lead me to this
conclusion.
The first is one of the new Humanware Brilliant BI 40x displays. APH
is selling the Mantis, but unfortunately (for me ) this has QWERTY
input, and I wanted the standard 8-key type. It's clear to me that
the Chameleon 20, Brilliant 20 are the exact same display, except
that APH is able to provide a lower cost to consumers by providing
the Chameleon under their name. This was similar to the PlexTalk /
Bookport situation. I burnt out the book port by accidentally
plugging in both the AC adapter and USB cable. Not a good idea,
kids.
Some
devices just don't turn off charging on both, and that can fry
internal things. So went the Bookport, but I did find a PlexTalk as
a replacement for it. So there's that.
There is, however, a big difference between the era of yesteryear
and the one of today. The Plextalk / Bookport used same firmware
structure, but both had different firmware files which could be
loaded on your model. The Plextalk was used internationally, so a
lot of European countries saw it, whereas the Bookport + was a U.S
exclusive.
Either way,
today we are faced with a world where both the APH devices and the
BI 40X models can use the same firmware file. They can run the same
build, and each will display their own hardware-driven differences,
such as Keysoft Light being used on BI 40X, but Mantis/ Chameleon
hiding those Keysoft things and presenting people with the right
user guide for their model.
How is this done? Surprisingly, the firmware for these devices is
more open than custom-built Humanware Apex arm platforms of the
past, or even the Everest-based bootloader boards used by a
BrailleNote touch.
They use simple .tar files for the filesystems, but there's good
signature verification on these files so you would need to generate
with keys you don't have if you were to tinker with the package.
From the get-go, the thing I liked and what surprised me is just how
much security is still considered in these devices, but we'll get
into this later.
Either way, I found a few surprises hidden in there. I can tell you
that the entire E-Speak speech synthesizer is in the current
firmware, indicating to me that they may expand full speech
functionality (or at least for book reading if not full speech)
using Mbrola based HMM synthesis technology. This is present today,
just not activated. There are also a bunch of sample .mp3 files in
the root user's home folder, which appears to be used when you get
these things in a diagnostic mode. (that part is still hidden to me,
which is good as again, it shows how well they can still restrict
security on a Linux
environment.)
This presents a huge opportunity for expansion in the future on
these devices. I found out that the way they can code for knowing
which you have is simple. These devices are built on off-the-shelf
hardware.
Specifically the SAMA5D3 Xplained User Guide -
Atmel-11269-32-bit-Cortex-A5-Microcontroller-SAMA 5D3 breadboard.
This is amazing. In fact, you can view the entire spec sheet for it
here:
http://ww1.microchip.com/downloads/en/devicedoc/Atmel-11269-32-bit-C
ortex-A5-Microcontroller-SAMA5D3-Xplained_User-Guide.pdf
So, we can tell many specs of the hardware right off the bat, and
that standard off-the-shelf parts power them, including a Cortex A5
chip and at least a gig of Ram. In their Linux implementation,
there's a /dev/brldsplay (or something similar, perhaps
/dev/brailledisplay)
which drives the Braille output at all times. This is also how the
"recovery mode" prompt can be displayed by the bootloader.
These
breadboards appear to have either 1 or 2 gigs of ram, and they pair
it with various Bluetooth chips in the hardware difference
process:
Bluetooth 5 for the BI 40x only, 4.2 for Bi 20x, Mantis, Chameleon.
What's interesting is that the famously talked about NLS ereader is
based off this same series also. This means that the EReader (as it
is known internally) has a 20-cell display (just like Chameleon, Bi
20X) and an exactly identical interface / firmware to these devices.
The
difference? Only the BARD online service will be accessible on them
with the "online services" menu.
That's right, here we get into more interesting things. The
Chameleon
right now excludes the BARD service, and it's a curious omission.
Perhaps agreements had to be made since the NLS product will have
that service, and it's exactly the same looking device. Either way,
all APH would have to do is to flip the switch on the menu item for
Mantis and Chameleon users, and they would get BARD listed. But at
this point, this could also undercut Humanware's products, although
the Mantis never will as it's the QWERTY brother to the BI 40x.
However, today, the Chameleon is about $300 cheaper over the Bi 20x,
and the only thing you miss out on is the BARD service. I've heard
rumblings from a few people that BARD support may still ultimately
arrive on the APH devices, and I think it should considering how
many students may need that support for their textbooks.
The other device I was able to acquire is an embosser. I'm still
looking for tactile graphics to use which are good to print, but
this can open up a bit more opportunities for me as well when it
comes to creating diagrams of things. One device that came with the
embosser is the GoBraille
You might be a bit surprised to know that the GoBraille is built on
a Raspberry Pi. That's right. When I saw the layout of the board, I
instantly knew. It has 4 USB ports + ethernet on the left, Micro-USB
in the back, standard HDMI in the back. Oh, and it announces its IP
address from the headphone port. How cute.
In a way though, you're also paying for the formatter and embosser
interface + custom drivers all that could require to print Tiger
graphics. Certainly making it air-print compatible over CUPS,
configuring how the embosser's Graphics VS text mode will work, all
of that requires a bit of custom coding. The frontend to the
LibLouis translator through the GoBraille web interface, it being
able to translate text when it comes across wireless printing, and
configuring the Wi-fi over Wi-fi direct + other extras that make
that device user friendly. Still, it's built on off-the-shelf
hardware. And that's a bit remarkable.
So Linux does have a huge place to carve out in the future of
assistive technology. I think many more things to come will be built
either atop Linux or Android, and this will propel them into the
future where more modern hardware can e used within these devices,
rather than hardware that's a few years old already by the time they
get to design all the custom motors and servos and whatever else to
interface with it. I know they have built .so Linux libraries which
drive some of this now, which opens up a potential of re-use or
easier re-configuration to fit a wide range of Linux hardware.
Just don't be surprised, because that Linux revolution is already
here, and we live among it. Now I just wish I could somehow localize
or help localize the Chameleon's or Bi X series firmware into
Hungarian. That would be amazing.
Sincerely,
Tamas
===========================================================
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The raspberry-vi mailing list
Archives: //www.freelists.org/archives/raspberry-vi
Administrative contact: <mike.ray@xxxxxxxxxxxxxx>
-----------------------------------------------------------
Raspberry Pi and the Raspberry Pi logo are trademarks of the
Raspberry Pi Foundation.
This list is not affiliated to the Raspberry Pi Foundation and the
views and attitudes expressed by the subscribers to this list do not
reflect those of the Foundation.
Mike Ray, list creator, January 2013
The raspberry-vi mailing list
Archives: //www.freelists.org/archives/raspberry-vi
Administrative contact: <mike.ray@xxxxxxxxxxxxxx>
-----------------------------------------------------------
Raspberry Pi and the Raspberry Pi logo are trademarks of the Raspberry Pi
Foundation.
This list is not affiliated to the Raspberry Pi Foundation and the views and
attitudes expressed by the subscribers to this list do not reflect those of
the Foundation.
Mike Ray, list creator, January 2013
The raspberry-vi mailing list
Archives: //www.freelists.org/archives/raspberry-vi
Administrative contact: <mike.ray@xxxxxxxxxxxxxx>
-----------------------------------------------------------
Raspberry Pi and the Raspberry Pi logo are trademarks of the Raspberry Pi
Foundation.
This list is not affiliated to the Raspberry Pi Foundation and the views and
attitudes expressed by the subscribers to this list do not reflect those of
the Foundation.
Mike Ray, list creator, January 2013
===========================================================
The raspberry-vi mailing list
Archives: //www.freelists.org/archives/raspberry-vi
Administrative contact: <mike.ray@xxxxxxxxxxxxxx>
-----------------------------------------------------------
Raspberry Pi and the Raspberry Pi logo are trademarks of the Raspberry Pi
Foundation.
This list is not affiliated to the Raspberry Pi Foundation and the views and
attitudes expressed by the subscribers to this list do not reflect those of
the Foundation.
Mike Ray, list creator, January 2013
