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== Network/Hardware Ideas ==


=== Microphone ===
== Microphone ==


===Sound Codec===
A built in Microphone would be usefull if dirt and echo/feedback could be controlled. If you have a microphone and speakers included with these laptops then then if you include a small peice of software they can be used as telephones or walkitalkies -- like an instant message local channel that is as easy to use as a CB radio. If the hardware looked like a radio, the oporator could use it before they learend how to use the computer.


The [[Hardware specification]] page says the Audio Codec is an [http://www.analog.com/en/prod/0%2C2877%2CAD1888%2C00.html Analog Devices AD1888], AC97-compatible audio codec.
===The provenance laptop===


The paper - 'The One Laptop per Child (OLPC) Audio Subystem' by Jaya (Alsa) provides useful information on the audio subsystem. The link is -
An issue about the provenance of the particular copy of the (yet-to-be) published program obtained for running by a child on a laptop has been written about in the http://wiki.laptop.org/index.php/Application_Program:_Test_of_ability_with_arithmetic#Verifying_the_program section of the
[http://www.kgw.tu-berlin.de/~lac2007/papers/lac07_kumar.pdf The OLPC Audio Subsystem]
http://wiki.laptop.org/index.php/Application_Program:_Test_of_ability_with_arithmetic page.
--[[User:Arjunsarwal|Arjunsarwal]]


===Microphone Sensor Input===
A possible solution has been suggested. This is termed a provenance laptop therein. It is different from the server version which is suggested above.


The microphone input can be used to measure voltage or (using the Microphone bias voltage) resistance. This should enable us to use this as a form of sensor input with the audio analog to digital converter converting the sensor signal to a signal that can be displayed on the screen or logged by the computer. More info is required on the use of the codec in this mode.
In view of the fact that the provenance issue is likely to be important for many programs, not just for the application program in relation to which the issue was raised, the idea of the provenance laptop is copied to this Hardware Ideas page.


* max voltage that can be withstood safely by the mic input
Would it be possible for there to be a special, variant, version of the laptop, say moulded in a colour different from the laptops issued to the children, which is read-only of files, with files being obtainable only over the internet and then only from one particular webspace? This special, variant, version is herein termed a "provenance laptop". The system software for such a provenance laptop could be in read-only memory. Thus, if the idea is feasible, a child could obtain files from a provenance laptop with confidence. The provenance laptop might, from time to time, need to be transported several miles to a place where files could be obtained from the internet. However, the availability of a provenance laptop facility in a rural school where there is no direct connection to the internet could be a good second best to having a direct internet connection. The provenance laptop could be used to select which files are obtained from the one particular webspace. The one particular webspace could either be a special webspace run by the government of the country where the laptop is deployed or a special webspace of the OLPC project run by the OLPC management under secure conditions, depending upon the policy choice of the government of the particular country.
* Voltage corresponding to AD converter full scale.
* Bias voltage output (open circuit)
* Bias voltage output (short circuit)
* Frequency range of mic input
* anything else?


===Uses of making measurement using the analog input port on the laptop===
=== Broadcast texts over shortwave radio ===
This section is useful for compiling a list of important and interesting uses for sampling analog input voltages using the analog input port of the laptop.It would also help in determining the end requirements of voltage range that would be required to be supported int he laptop at input.
A major challenge is providing access to information through the green machine.
Access to the Internet in most of the regions of the world where children will benefit
from the OLPC program is usually limited. Here's a hardware+software idea that could make access to information truly ubiquitous. It goes for _access_ as opposed to ''speed''. The idea works synergistically with other ideas such as Jason's idea for p2p distribution of texts and mesh network access to the Internet.


'''Rationale:'''
I see the green machine as (1) a tool for accessing information and (2) a tool for self-driven learning through investigation. A problem with the former role is "from whence cometh the information ?". With the limited storage resources, "pre-loading" the information on the machines seems like an untenable approach.
The crux of this proposal is that having ''easy and reliable'' access to a small library of information will be more useful than having spotty access to the entire Internet, even through mesh networking. The idea focuses on access to information, rather than access to the Internet, the latter and Information not always being synonymous.


Uses and their electrical requirements (Voltage range, bandwidth, Bias)
'''Idea:'''
Broadcast texts over shortwave radio. Have the texts broken up into
chunks, and all the texts from a library interleaved in time. If possible, transmit different interleaving sequences on a set of different channels. The basic
circuitry for a shortwave radio demodulator can be very simple, particularly if
the decoding is done in software sitting behind a straightforward RF and analog front-end. When a child wants information on a topic, the implemented system captures fragments of a text relating to the topic off the air, and over time, the whole text is collected.


1. Checking the voltage of an AA/AAA/C/D type cells- Should be able to sample DC in the range 0-1.5V
'''Example:'''
Purely as an example, let the library of texts being transmitted consist of (1) Project Guttenberg texts (2) (one thing I wish I had access to as a kid:) mathworld.wolfram.com (3) Some free encyclopedia.
All the content is broken up into packets of some size, encoded, all the packets interleaved according to some scheme, and the entire interleaved stream repeatedly transmitted. The infrastructure for transmitting the data streams need not even be in the nation or on the continent where the recipients are. Let, for example, the entire stream take two months to transmit. 4GB of encoded data at 1200 baud will take ~40 days. 1200 baud for a packet radio seems feasible, though I can't say how complex the hardware would be. Bear in mind we're only talking about receiving, not a full-blown modem.


2. Checking the voltage of a PP3(9V) type cell - Should be able to sample DC in the range 0-9V
'''Extensions:'''
You can imagine having ''N'' different interleavings, which are transmitted on ''N'' different channels. When a child wants information on some topic, the request is sent out to at least ''N'' other green machines, over the mesh wireless network. All the machines start picking up chunks for the text on one of the ''N'' different channels. The chunks are sent to the requester over the mesh network.


3. Checking the voltage of a car battery - Should be able to sample DC in the range 0-15V


4. Interfacing an LDR/photo voltaic cell/Temperature sensor - Bias voltage required . Voltage range =
That's the top level idea. I think it is feasible to implement with minimal hardware,
and the algorithms and their software implementations to go behind the hardware are interesting issues, many of which are already well understood or solved.


5. Robotics applications - The interface that is usually provided with commercial
--[[User:Pstanley|Pstanley]] 10:52, 1 February 2006 (EST)
modules such as distance ranging modules is a 0-5V digital output. If the output voltage interface is RS232 type then voltage sampling requirements extend upto -12V - +12V. But then the XO has a serial port ? (Yes, but the connector is not exposed. --[[User:Walter|Walter]] 20:58, 24 June 2007 (EDT))


--[[User:Arjunsarwal|Arjunsarwal]]
====USB addons====
Well, first of all, the OLPC has 4 USB ports. There is no reason why someone could not manufacture such a radio system as an accessory for the OLPC, to be used in those countries and those regions where this would be a good idea. This would most definitely be a dumb idea in the capital city of Thailand, for instance. But in mountainous western China it would be a very good idea, indeed.


--[[User:Doug|dlarue]] 07:02, 15 January 2008 (PST)
===Motorcycle Net===
There are already people using motorcycle delivery services to carry email from village to village. I believe it is in Vietnam but it may have been Thailand. This type of networking is likely to grow once there are large numbers of wireless capable laptops in place. They either exchange info wirelessly with the motorcycle, or, more likely, a teacher runs a village base station that can collect messages all week, then do a quick upload and download while the motorcycle driver is dealing with the paper mail. Bulk data transfers would be on CD or DVD since USB drives are readily available. The villagers will quickly learn how a single USB-CD drive can multiply the usefulness of those laptops 100-fold.

===Support for this and mention of telesoftware and of MHP===

Yes, good idea.

You might like to consider using telesoftware, that is the unidirectional cyclic broadcasting of software and its selective use, to broadcast software packages for the laptop as well.

The following webspace about the DVB-MHP (Digital Video Broadcasting - Multimedia Home Platform) interactive televison system might be of interest.

http://www.mhp.org

The MHP system broadcasts Java programs to interactive television sets.

The following idea, not implemented as far as I know, might be of interest in relation to digital radio.

http://www.users.globalnet.co.uk/~ngo/tor00000.htm


William Overington

5 March 2006

==== There is now a page about the possibility of an MHP to laptop interface ====

There is now a page about the possibility of an MHP to laptop interface.

[[http://wiki.laptop.org/wiki/MHP_to_laptop_interface_possibility]]

One way connection to internet helps nothing. This is passive usage like watching tv. Software distribution with USB is easy.

* Yet in areas of the world where a two-way link is impossible, a one-way system where lots of software and data such as electronic textbooks can be received from direct to school broadcasts from a geosynchronous television broadcasting satellite and stored localy, telesoftware could be very advantageous.

===Historical note about the ATS-6 experimental satellite===

Some interesting experiments in using direct satellite broadcasting for education took place in the 1970s using the ATS-6 experimental satellite.

http://www.nasm.si.edu/research/dsh/artifacts/CS-ATS6.htm

William Overington

6 March 2006

===Another historical note about radio broadcast of programs===

Back in the 8-bit era, when floppies were still not cheap enough, some computers had a cassette recorder so you could store your programs in cassette. A local radio used to broadcast Atari programs so you could record them at your radio receiver and then play them on your Atari. It wasn't very reliable, since line noise could spoil the recording, but it was a nice idea back then. .:|you could broadcast boot code, mesh-networking software patches, and links to P2P resources. Just include a standard FM receiver (but why not a programmable transmitter as well!), record and process audio into bits, but don't listen to the noise ... oww! [[user:N888|N888-9-AE]]|:.

[[User:Locoluis|Luis González]]

:: See [http://www.xs4all.nl/~lennartb/basicode.html Basicode] [[User:62.252.0.11|62.252.0.11]] 17:02, 17 March 2006 (EST)

12 March 2006


====Distance and the Mesh Network====

As I understand these laptops will have intergraded wireless with the 802.11 b and g standards. The problem I see is that in some countries, like Africa, the children live sometimes a half mile or so apart from each other. The 802.11 b and g IEEE standard only has a reach of 100 feet or more with out modifications. This means the only time the children will be networked with each other is when they are at school. What needs to be done is the wireless in each laptop needs to reach up to at least a mile so the children’s computers are always connected to the network even in their home. The wireless b and g standard can be mod up to 10 miles of reach but to do that requires either a large antenna or an amplifier that would consume too much power. My suggestion is that you create a new wireless networking standard with low radio frequencies like every one has been suggesting. I would like to see it so the children’s computers are always part of the network when they are at home, because as I see it most of the programs on the laptop except the office programs can’t work with out a network.
--[[User:68.66.231.5|68.66.231.5]] 06:52, 31 May 2006 (EDT)

====Speeds and data integrity====

If I remember my modem hardware correctly, 1200baud is simple FM over half of a telephone channel.
This would be more like a FAX channel where the entire frequency width of the channel is available; all normal fax modulations have a baud rate of 2400, with bps of 4800 to 14400.

The processor in this machine would be more than enough to demodulate this in software and decode some serious forward error correction [http://parchive.sourceforge.net/ eg par files]

[[User:62.252.0.11|62.252.0.11]] 17:02, 17 March 2006 (EST)



== Hardware/Accessory Ideas ==

=== Keyboard ===

==== Keyboard Light or Display ====

===== Keys with a light emitting diode array in each of them =====

I cannot remember where I saw the idea. It was in an article years ago and that article referred to a science fiction novel by Dr Arthur C. Clarke where the author of the article had seen the idea. I think that the novel mentioned was set in the future at the American Quincentennial in 2276, though I do not remember the name of the novel. The idea was that each key would be illuminated with a glyph of the character which would be entered into the computer if that particular key were pressed. In that way the keyboard would be software alterable so as to be suitable for a variety of writing scripts and languages. As we now have Unicode with many scripts encoded and each language not only needs its script yet may also need various particular characters, (for example, the different set of accented characters needed for Spanish and Portuguese) I wonder whether a feasibility study of whether such keys could be produced and what they would cost could be carried out by the hardware experts. They could perhaps be very useful in India where the keyboard could be switched by software from Latin script to an Indian script as desired. This could also provide the advantages of illumination which would otherwise be provided by keyboard backlighting or by illuminating the keyboard.

William Overington

2006-04-11 0818Z

:: Whoa! I think normal exchangable keycaps are just a little cheaper! :-) IMHO this would only be worthwhile if there is a pressing need to be able to change the keycaps dynamically. It might be useful for devanagari but the scripts that it would seem to be most useful for (CJK) seem to get on fine with software solutions. [[User:62.252.0.11|62.252.0.11]] 03:51, 12 April 2006 (EDT)

Yes the cost could be prohibitive. However, I have now thought of a possibility which could perhaps produce some of the benefits of such a keyboard. I have started a new section for it.

===== Keys with a small piece of electronic paper on each of them =====

I saw a television item about electronic paper technology. I found the following on the net.

http://www2.parc.com/hsl/projects/gyricon/

I cannot find a date on the document. Does anyone know how new is this technology?

Suppose that there were an option of a type of keytop for use on a laptop where the keytop had a piece of electronic paper built into its surface. Would that then mean that there could be a special gadget, which could be a laptop peripheral, which could fit over a keytop and reprogram the piece of electronic paper so as to display the desired glyph? Thus someone could, by a fairly slow, one at a time process, reprogram the glyphs displayed on each of the keys of the keyboard. This could mean that customized keyboards for various languages, such as those of Africa and India, could be produced in small quantities, even one off, relatively easily. Naturally, if electronic paper keytops were developed there could be machines made which could be used to customize the keytops in bulk; however, hopefully the one-keytop-at-a-time programming gadget could also be developed.

Does anyone know if the electronic paper technology could stand up to continual pressing with fingers?

William Overington

2006-04-13 0754Z


Some links regarding the electronic paper and electronic ink technologies.

http://www.paloaltoonline.com/weekly/morgue/monthly/1999_Mar_24.EPAPER.html

http://www.e-ink.com/

http://www.prism.washington.edu/lc/CLWEBCLB/electpaper.html

http://www.research.ibm.com/journal/sj/363/jacobson.html

''''Works for Me:''''

The following keyboard always worked for me, do these keyboards have removable keys or are they going to be sealed units to avoid dust and dirt damage, i like the idea given of luminous keys, or key LED's;

Perhaps an all in one peice of rubber keyboard like the grey one that was included in the old zx spectrum (if you took the cover off), there are not going to be as many lights or sinks to wash hands in I am presuming? Or even an eluminated surrounding area to the keys could be considered?

http://www.old-computers.com/MUSEUM/computer.asp?c=223


====Dvorak and V for 200million wrists====
If enough are to be manufactured, maybe it would not cost too much to
*Use an ergonomic split keyboard in the shape of a V for 200million healthier wrists
*Configure it with the Dvorak layout or some other better than QWERTY layout
--[[User:Rogerhc|Rogerhc]] 18:31, 28 May 2006 (EDT)
:QWERTY and its variants are standards (ISO, EN, DIN) with acceptable mappings when using with less common languages. Dvorak isn't a standard and as its layout is based soleley on letter frequency of the English language, it isn't of much use for non-english or non-programmers. The V shape takes too much room and would require a split rubber-membrane, which augments costs.
::English is a highly used international language. Many other languages have similar letter frequency. Chinese pinyin even does and is commonly used to type Chinese. Standards are driven by large projects like olpc. Keyboards can be built for hands. Is moving standards and design forward good policy for olpc? (I don't know but I ask. Little changes that work well maybe.) --[[User:Rogerhc|Rogerhc]] 16:14, 29 May 2006 (EDT)

==== Chord Keyboard ====

At the outset of the ''Computer Rennaissance'' in the 1970-s a few companies sold a five key ''chord keyboard'' which seemed to offer various advantages. The pioneering SRI R&D into collaboration (via the ''Augment'' project) may have used such a keyboard. Could be interesting to think about seeding popularization of such an arrangement on OLPC, PDA-s, mobile phones and TV remnote controls - maybe to augment full keyboards on OLPC.

[[User:Larry Pfeffer |L Pfeffer]] April 6,2006

I am developing a two handed chorded keyboard[http://www.merlintec.com:8080/hardware/29] (which also works with just one hand to make learning easier) for my project and it would be great if this would be useful for OLPC as well.

--[[User:Jecel|Jecel]] 15:20, 11 April 2006 (EDT)


=== Green Hardware ===

Some Ideas from [http://www.worldchanging.com/archives/003881.html WorldChanging]:
"...We typically discuss organic polymer electronics (OPE) as a feature of the fabrication future, but the clean leapfrog application is important, too. The production of OPE is much cleaner than traditional electronics, and the materials themselves contain few if any heavy metals. Recent OPE developments include a microprocessor able to run at around 100MHz (far slower than today's fastest laptops, but easily fast enough for the kinds of basic information and communication tasks described for the OLPC project), a variety of slower circuit and sub-processor plastics, an organic polymer battery and even a colorful, fast flat-panel display. Even the solar panels often suggested as an add-on for the hundred dollar laptop could be made with organic polymer materials."

=== Power and Batteries ===
When you look atentively at military pda,they are powered by fuell cell that isn't so avaliable in theses countries and is not in the price range being considered. We have to do something with the options avalabile...

==== Power over Ethernet ====
Have you considered using 802.3af or 802.3at Power over Ethernet (POE) to power and charge the laptops. You would need to add an Ethernet Jack, NIC, and POE circuitry. You could have one Ethernet switch per class room.

:: POE hubs are expensive here, but that's probably not the problem. CAT-5 cable will not be available in any location that doesn't already have a lot of computers, that's 100M of expensive cable for a classroom or 30 as opposed to about 30M of any 2 or 3 core cable they may have laying around for just power. Also I understand CAT-5 isn't good power cable, long runs at low voltage will waste half the energy that goes into the cable. [[User:62.252.0.11|62.252.0.11]] 03:19, 12 April 2006 (EDT)

==== Batt types and charges ====

If you are constantly recharging the battery all the time this will greatly decrease the life of the battery. I have a laptop and I always charged the battery whenever it was powered on. After only about a year my battery life decreased from almost 2 hours to less than 20 minutes. This must be considered when making the HDL.

p.s. visit my site at <a href="http://www.freewebs.com/laptopfreek0">Laptopfreek0</a>

or email me at <a href="mailto:laptopfreek0@yahoo.com">Laptopfreek0@yahoo.com

NiMH batteries do not suffer from "memory effect", in fact NiCd batteries don't normally either. But, both types do suffer from voltage depression; when they are fresh and new they give a voltage of 1.2v per cell so 8 cells will give 9.6v, a useful amount. But if the cell is over charged or just always on trickle charge the cell voltage soon drops to just about one volt per cell; just 8v total, the equlivent of removing an entire cell. The interesting thing is voltage depression does NOT effect the total capacity of the battery. I have NiMH and NiCd that are completely depressed (hmmm) but they still do the job as well as they did when new.

The problem with this is the discharge graph [http://www.uniross.com/UK/industrial/Product%5Ccharacteristics/010302]. You will notice that it's mostly flat so some designers take the 1.2v as gospel and design thier electronics to shutdown at 1.1v. If the battery is depressed by 0.2v this line comes in at about 10%..15% of the way into the capacity so you only get 10%..15% of your two and a bit hours of charge ... 20 minutes... [[User:62.252.0.11|62.252.0.11]] 15:42, 17 March 2006 (EST)


i heard that nicd and nimh batteries have some fake memory effect:
it was said that they were afected by another redox transformation than the normal,when they keep staying pluged on after having fully recharged the batteries:
this redox transformation will divide the battery in 2 and have a part with the normal voltage and another part with an inferior voltage
usualy that caan be easely detected because there is a voltage jump and so they needed to be full discharged with a resistor in order to get back their capacity but i don't remember the formula for calculating the value of the resistor
[[User:213.189.165.28|213.189.165.28]] 19:48, 4 April 2006 (EDT)


==== External or Removable Crank ====

Re: Ideas to make the crank external.
Hand cranks are an awful way to power anything excepting a hand drill!
Instead, how about a small single-action or rocker device the size of a
sewing machine floor switch? A single user could provide his own power by
either pressing and releasing (return being spring-powered) or rocking a pedal.

Wasn't there a group looking into human-powered options, like modifying bikes to power laptops or the rocker actions you suggested? --[[user:mchua|mchua]]

Option could be to have the crank removable with a socket that could double to allow other devices, such as pedal,
tredal or any external turning mechanism (wind power) to power the laptop. --[[User:Hckhckhck|Hckhckhck]] 09:58, 24 May 2006 (EDT)


=== Microphone data input ===
=== Microphone data input ===


The microphone input jack can double as a dataport for some class of devices (when supporting a "DC-coupled" input mode), but a more general-purpose USB analog to digital device would be a great peripheral for the laptop. --[[User:Walter|Walter]]
The microphone input jack can double as a dataport for some class of devices (when supporting a "DC-coupled" input mode), but a more general-purpose [[USB peripherals|USB analog to digital]] device would be a great peripheral for the laptop. --[[User:Walter|Walter]]

=== AD/DA & "Parallel" interfaces ===

:::: Precisely for these types of ideas the computer needs some sort of basic A/D, D/A and suitably protected bi-directional "parallel" type interfaces. These need to be built-in so their use doessn't add wire spaghetti, cables/conversion boxes don't get lost, is "fumble free" and always available. In short, it must be '''simple''', '''empowering''' and an '''idea generating catalyst'''. [[User:Larry Pfeffer |L Pfeffer]] March 20, 2006

* Or perhaps these miscellaneous fun things should all be available on a USB interface. It would keep it very expandaple, yet low base cost. USB devices keep getting less expensive to develop. --imajeff


=== Serial Port?? ===

I know it can be done thru USB emulators... but serial ports are simple and easy to use. If someone wants to make some electronic project, or using old hardware (mouse, or serial comunications devices), it could be useful to have one.

it's just an idea, but I started making my first hardware projects with this, and even today is cheaper (at least here in Argentina) and easy to make serial ports working hardware (rather than buying PICs and programming them).

And still many hardware has serial ports (networking devices for example).

[[User:Gandolfi|Gandolfi]]

:::: Serial ports are NOT robust, at least nine tiny little pins that it's very easy to bend or break, not a good idea. Perhaps with a more robust connector, though IME the parallel port was more useful for electronics projects. [[User:62.252.0.11|62.252.0.11]] 16:02, 17 March 2006 (EST)
:::: The photos from the developer boards show an external RS232 level shifter circuit attached (to some GPIO pins?). Legacy serial/parallel ports are nice for experimenting, there's IMHO no need for this for a laptop which is targeted at 6-12yo childs.
:: Not to mention the fact that there IS NO OLD HARDWARE in these 3rd world villages. It would be far better to have an external power plug with circuit breaker switch so that people could use the old bananas they have laying around TO MAKE BATTERIES!!! The kids will be motivated to find a way to pedal less so lets help them learn some science.


=== Additional Architectural Elements ===

The envisioned manufacturing scale of the envisioned initiative can dramatically reduce hardware feature/sub-system costs and some important features are very inexpensive to add. Among these are '''IrDA''' (for wireless connectivity to a variety of existing/emerging devices), built-in '''computer tunable multi-band radio receiver''' with the minimal hardware required to extract also data transmissions sent using various methods (e.g. FM side band), at least minimal '''AD/DA''' and '''parallel I/O''' with suitable port enabling children to use the computer in laboratories and tinker with science/control and computer controlled toy applications/games.

If the CPU chip is custom made some of the above (e.g. AD/DA)and possibly '''3D graphic acceleration''' and maybe even '''CCD''' etc. section (for camera) may be added without increasing cost. If operation of the augmented CPU+ chip sub-systems is optional then perhaps sub-systems would only receive power if/while they are used. Thus there may not necessarily be a power penalty for extending this aspect of system (+CPU chip) capability. Alternately perhaps these types of features would be on one custom chip.

Along same line of thinking, it would be useful if '''hard disc and CD/DVD controller circuitry + interfacing''' were included with suitable empty bays. This way children and their families could save money for add-ins and easily install them.

One wonders why '''10BaseT''' is not included,unless that would add significant cost(unlikely).
:: Wireless provides general networking without a fragile cable, a moderatly robust USB ''Crossover'' cable would be as fast or faster than 100BaseT. [[User:62.252.0.11|62.252.0.11]] 15:50, 17 March 2006 (EST)

::: True. Yet, there are many "Wired LAN-s". How would the computer plug into such a network (ideally in a Plug&Play Mode") if there is no money for wireless hub? Of course wireless hubs are quite inexpensive, and maybe it can be assumed that in a few years they will be ubiquitous.

:::: Ermm, one of these lappies could be a wireless hub with a USB <-> 100BaseT connector. Though I wouldn't be suprised if the local school gets a [http://www.ndiyo.org/ Ndiyo] base station at some point which would probably be expensive enough to justify having a wireless link for the lappies built in. I suspect the thinking is that USB is sufficiently ''Universal'' that it means there's no compelling need for other interfaces (Edit: I mean wired ones). That is after all one of the basic design features of USB. [[User:62.252.0.11|62.252.0.11]] 16:38, 17 March 2006 (EST)

::::: Unlike "Wired LAN-s" USB has distance limitations. Also, "legacy environments" are built with wired LAN-s. If cost of 10BaseT/100BaseT on silicon +connector is trivial or converges to $0 in millions of quantities it is better to add also that interface, since it has no appreciable cost, and empower users decide how to set up their school/club networks. Of course, in some cases "thin client" (back to "time sharing") architectures may be preferred in some schools (e.g. Skolelinux: www.skolelinux.org [http://www.skolelinux.org]) - and, of course, the goal is to be "self contained" when the laptop is out of the school/club (in the originally envisioned "Dynabook" spirit).

::::: It is good that the base system specification supports BOTH wireless and USB. The more choices the more opportunity for creative solutions suited to local tastes and cultures. For this reason IrDA ought to also be added since, it too, interfaces to legacy systems, provides yet another choice in some situations and is essentially a near $0 cost add-on. Also, it could be used in environments like school busses and school yards for spontaneous peer-to-peer networking - when a USB cable may not be readily available.

::::: Regarding school busses, etc. thought should be given to how charging power could be provided for a number of units during a ride to/from school (assuming there are school busses). Also, "battery charging" could be a useful school service . Hopefully a well funded organization like UN could be stimulated to think creatively about providing grants, etc. to actually help developing nations successfully embrace such innovative initiatives. (Yet to be seen if the UN can respond to any such challenge. Would be of interest to know what if any contribution Mr Kofi Annan made to the initiative via UN channels after the Tunis demo/photo opportunity.) [[User:Larry Pfeffer |L Pfeffer]] March 18, 2006

:::::: I agree, both wired and wireless have ''compelling advantages'' so it's right to include both. But a 100BaseT connector has the disadvantage that it's not robust, you can destroy the socket by sticking a pen in it and the ''clip'' on a cable will fail without being abused. Even if the cost of an ethernet connector is zero at day one IMO it's likely to cost in some way for repairs or become unusable in short order. IrDA is certainly robust enough but it's range is very limited and as far as I can tell the only legacy devices it connects to are old laptops that cost $1000's when new and the odd printer, the IrDA spec is actually incompatible with the vast majority of Infra-red devices.

::::::: I was not aware of 10BaseT/100BaseT connector fragility. That can certainly be a problem Maybe the answer is assuring that schools/clubs have wireless coverage. That is inexpensive even without volume purchase

::::::: Palms, IPAQs, cell phones etc. have infrared capability.One would hope the laptop would seed an add-on after-market in toys and games - say wired an wireless controlled/sensed "Fun Things" (see below). If there was infrared support some manufacturers may chose to use it\ rather than WiFi and presumably the costs for infrared are lower in such "peripherals". Also, there is a message in having options and choices, such as BOTH WiFi and infrared for wireless. Options and Choices are not even taken for granted in a country like the USA and even less so in Europe. In poorer countries there is lesser empowerment and encouraging children to think in terms of choices is important. [[User:Larry Pfeffer |L Pfeffer]] March 18, 2006


:::::: It's very difficult to damage a USB socket. Before now I've managed to break the connector off a USB-Flash drive in the socket, the socket was undamaged! Even if you manage to break the tongue in the socket it can still work.

:::::: The problem with power on a school bus is that it's have to come from the diesel powering the bus, diesel costs money and is an inefficient power source even here. Much better to provide power in the classroom where it can be cabled in from whatever source is cheapest/easiest at the time. [[User:62.252.0.11|62.252.0.11]] 08:14, 18 March 2006 (EST)

::::::: Probably there are cases where busses may not have to burn much if any excess diesel to generate the kind of power needed for charging some laptops. Would be useful to see a back of the envelope engineering analysis of the possible "spare power" opportunity. Ideally the unit's charging section would be "smart" and not put drain on the charging system once the battery is charged. Also, the power generator add on to a bus would be sensor based and have an option to couple to the bus mechanism only if the bus is going downhill or at least on level ground - and de-couple while going uphill. Etc. There must be an optimization opportunity here (and room to think of the bus too as a "system" - and find a way to add a computer to it for this and perhaps other tasks which are cost or otherwise justified. (As with many choices there is also a BOTH option - support both in school and on busses ...) [[User:Larry Pfeffer |L Pfeffer]] March 18, 2006

Hopefully it will be easy to '''add memory for program execution''' - maybe the way FLASH memory is added to cameras.
Similarly, it should be possible to add FLASH capacity via '''FLASH memory cards''' from consumer electronics appliances (e.g. one of the standards from digital cameras). NOTE: neither of these should be via the USB port, but via recessed slots in back or bottom of case. They should be non-intruisive augmentions - much like FLASH cards in digital cameras.

Designing the the system to be an extensible framework is a key architectural choice.

Two exciting extensions or a separately packaged/priced augmentation unit ought to be considered.

a) a laser/etc. based '''MEMS chip+optics based projector''' which could give the system a large screen on a wall etc.

b) some linkage to '''electronic paper'''. In fact this endeavor could accelerate commoditizing ePaper technology

Seems that even if a few add-on hardware features would raise price target to say $120 this could be well worth it.

[[User:Larry Pfeffer |L Pfeffer]] March 17, 2006

:::: It should be assumed that in some cases the system may run off a car battery. Would be interesting to know how long it could operate off that source. Would be useful to have as part of the product line at least three low-cost kit based accessories for power based on solar, hydraulic, and wind based generators + battery. There must be such kits already developed for use in poorer countries.

I actually live in the third world and let me tell you there are no school buses. Children either walk to school or take a regular bus. I think it's very important to make these cases waterproof and shock resistant.
Gigi (From Venezuela)

=== Old style light sensitive pens ?? ===

Old style light sensitive pens ?? maybe a touch screen it's expensive... but I use to have one of this pens with my Commodore 64. It was attached to my tv, and I don't know if it can made in LCD screens. But this could be an option. Of course it needs a cable, but it can work as an "anti losing the pen system". Who didn't lost the pen of the PDA once ?? :) (I don't have one, but my boss always..)

[[User:Gandolfi|Gandolfi]]

Light pens depend on the fact that a single pixel at a time is being illuminated on a CRT. On a STN LCD whole lines are scanned at a time while on a TFT LCD (as OLPC will use) the whole screen is constantly illuminated. Another problem is that blood flows from the arm while using a light pen on a vertical screen so users get tired very quickly.

[[User:Jecel|Jecel]]

Thanks for the explanation Jecel...

[[User:Gandolfi|Gandolfi]]


=== ORP 12 ===

Moved to [[Hardware Ideas - Fun Things]].

=== Including built-in streaming from e.g. teacher to students ===

Would the current architecture, including display design/resolution/framerate etc. allow for this in principle?

On the software side, how about some peer-to-peer streaming stuff; one CD or DVD drive/player per school class, and groups of kids watching a (same) movie on several laptops? This is possible with e.g. VLC - but could be built-in, preconfigured/high-lighted and very simple - thingie pops up saying "A neighboring laptop has started streaming video, would you like to watch?" - done.

The hardware exists off the shelve... but will they all work out of the box? Drivers? Can player software be included in the "default" software? If not a full-blown "certification" program, at least at page (on this Wiki!) with "external devices known to work" (or if not, instructions on how to get them to work will probably be needed.

[[User:Vorburger|Vorburger]]

== Not a laptop, but an X-Term! ==

<b>Is anyone willing to consider a more immediately available, dumb-terminal version of the device which would have nothing more than a touchscreen and an ethernet port?</b>

:: I WANT! A small silent X-Terminal/Media player connected by WiFi/Ethernet to a big box will be a killer app for the Linux based home or office network. Doesn't work with Windows, Microsoft see to that. This is a different spec to the OLPC though, you'd want POE or better yet network over 6-pin firewire (firewire is designed to supply lots of power) you'd probably want a 1024x768 full colour screen and perhaps more memory. This is the $2000 version of the PC. [[User:62.252.0.11|62.252.0.11]] 03:35, 12 April 2006 (EDT)

== One PDA per teacher (100GB/200$/Same functions as Laptop) ==

How about making a pocket Linux like the [http://www.archos.com/products/ip_centric/pma_400/index.html?country=global&lang=en Archos PMA 430], built for less than 200$, with same functionalities as the 100$ laptop, but in a pocketable form factor and with a 100GB 2,5" harddrive inside. This device would also have a camera built-in, the teacher can use it to film documentaries and lessons to be used in education, and put up on the video server, for all students to be able to watch past lessons as video-on-demand.

So this device would be 100GB in the pocket and a camera, as well as it lets the teacher access all the same Linux software that is on the Laptops, and he can update the planning and the lessons for all students to access at any time of the day.

:: Why not also for kids? There may be a "right size" for kids' computers. Possibly a Palm/iPAQ size device may be too small - even if an integrated laser beam based full size virtual keyboard and virtual (projected) screen are available. The main reason for "right sizing" to notebook range size is to assure the system doesn't easily get lost. On the other hand ... one could then argue that cell phones too should be "right sized" to be at least notebook sized, but we seem to be able to do well with the current smaller size. So ... perhaps a kids' computer could be Palm/iPAQ size with a full size virtual keyboard/screen. By the way ... wonder what is the real internal parts +assembly + test + packaging cost to manufacturers of various models of iPAQ or Palm or what would be wholesale prices in 1 and 10 million batch quantity. In such stellar quantities manufacturers would be glad to make a custom version capable of running the OLPC software suite and envisioned interfaces. There may be significant advantages to this approach ... Another thought is that many programs support "skins". Why not the OLPC computer - with different shape, size, etc. casing based on a common "engine" (and crank)? [[User:Larry Pfeffer |L Pfeffer]] March 20, 2006

:::A "teacher" laptop could do the same thing...and is a less difficult platform,because embedded platform lend to technical dificulties...
you have several problem with this aproach:
*Hardware problems
**battery life
**price(too high technical specs)
**inavalibility of hardware
**size
*software problems
**different cpu architecture than x86
***cross compilations problems with some packages such as kde...

a device such as the pma400 isn't the right thing for puipils or teacher because of a lot of factors,first there is the hdd problem,a hdd consume a lot and is not that reliable but also the ram problem because theses devices have so little ram,for example the specs of the pma400 are:
*30 GB 1,8" hdd that is too much and isn't cheap
*omap 5910 @ ~150mhZ that is an arm9
*64 MB(i think) of ram with 41/42 MB usable on an EMBEDDED os that is very light...
*not a lot battery life due to the hdd...
*320x240 screen that is problematic
*not hardened
*non standard battery components=>higly problematic...

if you construct a better one you'll have:
*soc
*30 GB
*640x480
*128MB ram
that kind of device is a lot superior than the devices in america,europe or asia and would be resold...
if you want a better one you'll have:
*no hdd:flash
*x86 cpu
*128 MB ram
*flash
*hardened
*bigger...
so you'll have the same olpc than the one we have already
there is also a big prolem!!! there is no keyboard!!!
it will be very different from the computers beeing used in buisness and that will disavantage them while adding no counterpart

: Perhaps one can rethink screen/keyboard approaches as follows:
:: a) having a current style PDA touch sensitive small screen. Many people get by with PDA-s and do some useful things on even smaller cell phone screens ... (I know someone who few yaers ago wrote a serious book on a PDA while waiting for airplanes etc. He used an external keyboard.)

:: b) having a laser (or LED?) large format projected virtual screen/keyboard. This could provide the standard localized keyboard layout

: Perhaps a PDA variant could be co-developed by one or more vedors with capability to snap into a "secondary skin" which is similar to currently envisioned OLPC case, crank et al. This would be an "expansion box" and power source - with added memory, its own battery etc. capable of charging the PDA, ports, etc.

: Maybe software problems noted above could be prevented by a dual processor chip - with on-board non-x86 '''and''' x86 processor. The former used in PDA mode and the later in "inserted mode" - and power management to assure only the required procesor is active (and draws current).

: [[User:Larry Pfeffer |L Pfeffer]] April 6,2006


== Old thoughts ==


A built in Microphone would be usefully if dirt and echo/feedback could be controlled. If you have a microphone and speakers included with these laptops then then if you include a small piece of software they can be used as telephones or walkie talkies -- like an instant message local channel that is as easy to use as a CB radio. If the hardware looked like a radio, the operator could use it before they learned how to use the computer.
== Make it for us, too ==


These are ideas related to both audio input and output. Please review the [[hardware specification]] to see what is already included. Some audio-related ideas are also dealt with in the [[Radio and Broadcast]] page.
Be prepared: the whole first world will want to buy the 100$ pc.
Commercialise a first world 120$ pc, the same as the 100$, for us. The 20$ will be for south world schools.


== Librivox ==
--[[User:87.4.183.151|87.4.183.151]] 06:16, 17 March 2006 (EST) Francesco R.


Human-read audiobooks for children as well as literature are going to be included in the OLCP project via content packs. A recurring idea I've seen crop up a few times is that of children recording their own audiobooks in return. What is the final quality of the built-in microphone?
Exactly my opinion! I would buy one immedialely, just out of curiosity, for playing around with it and maybe to develop software for that platform


[[Category:Hardware]]
--[[User:Dzubi|Dzubi]] 06:45, 5 April 2006 (EDT)
[[Category:Hardware ideas]]
{{cleanup}}

Latest revision as of 07:13, 17 December 2008

  english | 한국어 HowTo [ID# 187591]  +/-  


Microphone

Sound Codec

The Hardware specification page says the Audio Codec is an Analog Devices AD1888, AC97-compatible audio codec.

The paper - 'The One Laptop per Child (OLPC) Audio Subystem' by Jaya (Alsa) provides useful information on the audio subsystem. The link is - The OLPC Audio Subsystem --Arjunsarwal

Microphone Sensor Input

The microphone input can be used to measure voltage or (using the Microphone bias voltage) resistance. This should enable us to use this as a form of sensor input with the audio analog to digital converter converting the sensor signal to a signal that can be displayed on the screen or logged by the computer. More info is required on the use of the codec in this mode.

  • max voltage that can be withstood safely by the mic input
  • Voltage corresponding to AD converter full scale.
  • Bias voltage output (open circuit)
  • Bias voltage output (short circuit)
  • Frequency range of mic input
  • anything else?

Uses of making measurement using the analog input port on the laptop

This section is useful for compiling a list of important and interesting uses for sampling analog input voltages using the analog input port of the laptop.It would also help in determining the end requirements of voltage range that would be required to be supported int he laptop at input.


Uses and their electrical requirements (Voltage range, bandwidth, Bias)

1. Checking the voltage of an AA/AAA/C/D type cells- Should be able to sample DC in the range 0-1.5V

2. Checking the voltage of a PP3(9V) type cell - Should be able to sample DC in the range 0-9V

3. Checking the voltage of a car battery - Should be able to sample DC in the range 0-15V

4. Interfacing an LDR/photo voltaic cell/Temperature sensor - Bias voltage required . Voltage range =

5. Robotics applications - The interface that is usually provided with commercial modules such as distance ranging modules is a 0-5V digital output. If the output voltage interface is RS232 type then voltage sampling requirements extend upto -12V - +12V. But then the XO has a serial port ? (Yes, but the connector is not exposed. --Walter 20:58, 24 June 2007 (EDT))

--Arjunsarwal

--dlarue 07:02, 15 January 2008 (PST)

Microphone data input

The microphone input jack can double as a dataport for some class of devices (when supporting a "DC-coupled" input mode), but a more general-purpose USB analog to digital device would be a great peripheral for the laptop. --Walter

Old thoughts

A built in Microphone would be usefully if dirt and echo/feedback could be controlled. If you have a microphone and speakers included with these laptops then then if you include a small piece of software they can be used as telephones or walkie talkies -- like an instant message local channel that is as easy to use as a CB radio. If the hardware looked like a radio, the operator could use it before they learned how to use the computer.

These are ideas related to both audio input and output. Please review the hardware specification to see what is already included. Some audio-related ideas are also dealt with in the Radio and Broadcast page.

Librivox

Human-read audiobooks for children as well as literature are going to be included in the OLCP project via content packs. A recurring idea I've seen crop up a few times is that of children recording their own audiobooks in return. What is the final quality of the built-in microphone?

This page needs clean-up and editing for coherence, clarity, and completeness.

Please improve this article if you can.

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