Alternative Design For The Ppz

[Da_Blitz]

I personally don't want a view-only device

then attach the keyboard

i didnt mean that as an insult, just to point out how brilliant that type of thinking was by seperating the keyboard and thecase

i do plon to make the keyboard usb connection a swivel joint. i want to have it so that it can support the upper half and if there are strength limitations then the upper half minus battery (as i would rather the battery in the keyboard in that case)

this would be a really good place to use miniusb plug. so perhaps there will be a return of usb client. that way i would have to have the flexible charging arrangment so that when it is plugged into a PC/keyboard it charges while when it discharges

i am thinking the screen PCB should be as large as the screen and flat and we use a flat batteryas large of the screen, lukiy for me i have found a supplier for battries that is the right size for above

basically i helped my grandfather set up an RC plane shop as he is an avid flyer who just retired who i convinced to start up a hobby shop to fund his plane purchasing as well as keep him occupied. anyway i was unaware of the scope he would take when starting somthing like this up and basically he flew into china and set up some contacts for plane suppliers and parts. basically i can now get Litium ion battries for RC planes that are very thin and are a bit smaller than the lcd screen on the Z and they are in series!!!

what does this mean, well they are 7.4v @ 2200maH, and there are 3 bonded together, so i cauld put 3 in parrelel and get 6600 maH at  about 2.8v or i could just use one and get a nice thin case. your choice if you only want one battery in the Z then you get 2 spare battries. plus they are cheap  and i may be able to get custom sizes for this progect as the RC plane people arent that touchy about size, they want low weight

Yeah!!!! one problem solved. now all i need to do is decide on a screen size as that will be the sive of the PCB, how does 5.8" sound  in truth its more likly i will use a 4" screen with a thin boader (sound on keyboard)

[stampsm]

4 inch screen sounds good. sharp makes one LS040V7DD01 that is 4" 640x480 or 320x240(switchable with a line into the lcd so you can have a switch over to 320x240 for older software compatability). i could not fid any pricing on this, but sharp make a 3.7" model that is the exact same but just smaller. LS037V7DW01 i saw these run at 128 USD at 100 qualtity purchasing from a distributor.

are those batteries Li-polymer or LI-ion batteries?

[chiark]

No insult taken

The nexio failed because whilst it was possible to attach a keyboard, it was impossible to use apart from as a thumb board.  If the keyboard is detachable then that's great, but if it can function as a screen protector and - importantly - the hinge is strong enough to support the weight of the screen then that's a winner.  You've already said that that's a design goal, so that's brilliant.

If possible, I'd love to see a 5" (or slightly bigger) screen in there like the Nexio uses, or like the Sigmarion 3 uses, running 800x480 resolution.  It really makes a massive difference to usability as I'm sure you're aware.

How about planning on a 5.8" board and allowing a choice of screens?  The 4" could have a icon panel to make up the size, and the 5" would drop straight in.  Would that keep options open?

[craigtyson]

An odd idea I had in the bath last night....

Assuming you have WiFi

Have your PDA with a 4" touch screen and a VGA/DV out

Have a Larger Touch / Flat screen (normaly used on the PC) with a docking slot for the PDA.

Why?  This would allow you to use the PC as normal, or use a terminal session / VNC session to the PC from the PDA using the same screen as the PC when in the house,or using its own 4" display while out and about.

To expand the idea a little further a range of screens with docks could be produced in several sizes to suit. posibly 5", 7", 10" and up as a mobile tablet form facter but with your pullout PDA at its core.

[wsuetholz]

I like the idea of having the keyboard be a bluetooth keyboard (wireless).
The major problem I see with that, is the need for it's own battery then.

We already have BT in the design, and you can still have stero speakers in the keyboard, the speakers would be another BT device.  

Maybe have the keyboard have a slot on the end, and the hinge of the display(slate) be long enough to act as a stand, which would also fit in the slot in the keyboard.  That last bit requires some additional thought....

I would also like to put in a vote for the 800x480 display..

Has anybody explored the display that is being developed for the OLPC?  According to their web page the developed one that is low cost, and very nice to the battery.  Maybe a smaller version could be sourced?  Maybe they would be interested in a companion One PDA Per Child :-) to go with the One Laptop Per Child..  That Wireless MESH stuff looks interesting.

Bill

[Da_Blitz]

chiark: ill have to look at avalible LCD's before i can make that desison, perhaps if it was a 5.6" in a 16:9 format and a 4" 4:3 then at least one dimension should match up (which is what i want, i dont like to waste space) however a respun bouard with more on the pcb would be a better choice for a 5.6" screen

a2dp on linux isnt up to scratch last time i played with it, i might have forgotten a flag however but there is a known problem where exacttly 90 mins latter the kernel hangs  so i hope they have fixed that up

actually i have had that idea about vnc, but the way i see it is that it could be done better, in fact i am writing a libary at the moment for remote resource sharing (keyboard mause screen) mainly for sharing of the command line that allows for hotplugging of screens (local and remote) i dont think it will be that popular but i hope it inspires the X11 people as the KDE NMM project has somthing simmilar that only allows mirroring of hot plugged screens, not extension of desktop

but in the short term VNC, or even better raw X11 would be an option (X11 so that your PC does the actual rendering work while the PDA issues orders, basically you get a bit of extra performance on heveily graphical stuff and the ability to play openGL stuff on non DRI apps)

wirelees mesh networking is somthing i have been folowing and i quite like the OSLR stuff. that screen could be handy but ill aim for 4" at the moment

finally BT would be nice however ATM ill stick with USB as then i dont need a seperate charge connnector however it would be somthing to look into.

the other reason for usb is so that we can put things like an sd card reader in the keyboard instead (or an extra 3) or extra usb ports.

[chiark]

every 5" panel I know of runs at 800x480, so is widescreen.  It's not 16:9, it's 15:9

Good luck with this.

[MONVMENTVM]

I personally wouldn't like a detachable keyboard as there are again 2 parts which I need to take with me. I would prefer something like the classical handhelds (jornada 6x0, 7x0 or the nec mobilepro) but in a smaller size. Something between the Zaurus and these Jornadas would be perfect. So I thought about this Nintendo DS Lite shape about which I wrote here:
https://www.oesf.org/forums/index.php?showtopic=21563&st=0#

By the way a 5" widescreen display (which I would prefer) would fit perfectly into this shape.

Here the picture I posted into the other thread (just think of the handy size of the Nintendo DS lite):

[a href=\"http://imageshack.us\" target=\"_blank\"]. So the real thing which made me buy the Zaurus was the keyboard (and of course the microdrive and OS).

And for alternative keyboard designs you could make a poll with options (i.e. handheld-like, zaurus-like or whatever) and see which type of keyboard is prefered.

hmm... now I've got an idea:
Why not build the case (i.e. something like the zaurus, nintendo ds, handhelds or whatever clamshell device) with the base unit and display unit and make the keyboard modular. Something like a changeable top-"cover" of the base unit. I hope you get what I am trying to say.
If someone wants to buy the pocketpenguin with keyboard type A, then the base unit gets assembled with keyboard type A. If another customer wants type B you just assemble it with keyboard type B. The connectors and dimensions of the keyboard would be the same but you can alternate with the type of keys and so on.

Cheers

[Da_Blitz]

the detachable keyboard is still a good idea if you understand it fully, let me explain

by standerdising on USB it defines a keyboard interface, which is very nice for me as it makes thins simple, by using a standard interface we can also pulg other acsecesorries into it.

even if the keyboard is detachable i have said that i am making the joint rugerd as i see it as bieng the weakest part of the desin. if you want a heavy keyboard that is fine as it really dosent have much to do with the connector because i want to make it a requirement that the battery be in the addon pack.

now if you dont want a keyboard this may seem wierd unless you make a battery pack that sits flush with the back of the screen that plugs into the usb port. makes changing battries very easy  and we could chuck a usb hub chipset in there with the battery so when you get home you can plug in

now you mention a changeable keyboard, at the moment i am saying put the cpu and ram inside the screen part and make the keyboard only contain the battery and some extra IO (eg a usb hub and perhaps an extra sd card or usb flash disk) doing this means you can have a tablet by just dropping the keyboard and plugging in a usb battery pack, one other advantage is that you have a usb abttery pack that can be used to power other devices.

one isde effect is that i can now EM shield the entire design as its all in the screen and i dont have to worry about a rotating cable that gets fed to the screen, not to mention the shorter cables  this isnt without disadvantages, one of them bieng that IO on the Z becomes limited because i am trying to minimise the hieght of the screen, if you dont mind a thigker screen and thinner keyboard thats great.

i could however make the suondcard USB as well as the SD card readers and the CF card readers meaning you could have more than one and dirvers are not a problem. and in the case of the sound card you get better isolation from the sound or noise of the main processor. the problem is that its backpack dependent so that going to a battery only pack means you just lost sound  it also pussehs up the price of teh backpacks. it also means the backpacks ore more custom than the screen/CPU which would only come in 2 or 3 diffrent models with diffrent ram cappacity and depending on the price of the wifi chipset, with or without wifi (if its less than $15 then this wont be an option as ram is the most expensive)

whereas the keyboard might come with diffrent sd/CF options, diffrent audio options, diffrent usb port options

anyway back to the point (or [/rant] how do you feel about what has been said and can anyone offer me an opinion, in terms of echonomics putting the stuff that can be changed in the keyboard/battery part means a cheaper cpu board as more of them are identical (ie non need to maintain diffrent models) which can be futher exploited by only offering it in 128MB RAM designs with wifi

[BarryW]

the detachable keyboard is still a good idea if you understand it fully, let me explain

by standerdising on USB it defines a keyboard interface, which is very nice for me as it makes thins simple, by using a standard interface we can also pulg other acsecesorries into it.

even if the keyboard is detachable i have said that i am making the joint rugerd as i see it as bieng the weakest part of the desin. if you want a heavy keyboard that is fine as it really dosent have much to do with the connector because i want to make it a requirement that the battery be in the addon pack.

now if you dont want a keyboard this may seem wierd unless you make a battery pack that sits flush with the back of the screen that plugs into the usb port. makes changing battries very easy  and we could chuck a usb hub chipset in there with the battery so when you get home you can plug in

now you mention a changeable keyboard, at the moment i am saying put the cpu and ram inside the screen part and make the keyboard only contain the battery and some extra IO (eg a usb hub and perhaps an extra sd card or usb flash disk) doing this means you can have a tablet by just dropping the keyboard and plugging in a usb battery pack, one other advantage is that you have a usb abttery pack that can be used to power other devices.

one isde effect is that i can now EM shield the entire design as its all in the screen and i dont have to worry about a rotating cable that gets fed to the screen, not to mention the shorter cables  this isnt without disadvantages, one of them bieng that IO on the Z becomes limited because i am trying to minimise the hieght of the screen, if you dont mind a thigker screen and thinner keyboard thats great.

i could however make the suondcard USB as well as the SD card readers and the CF card readers meaning you could have more than one and dirvers are not a problem. and in the case of the sound card you get better isolation from the sound or noise of the main processor. the problem is that its backpack dependent so that going to a battery only pack means you just lost sound  it also pussehs up the price of teh backpacks. it also means the backpacks ore more custom than the screen/CPU which would only come in 2 or 3 diffrent models with diffrent ram cappacity and depending on the price of the wifi chipset, with or without wifi (if its less than $15 then this wont be an option as ram is the most expensive)

whereas the keyboard might come with diffrent sd/CF options, diffrent audio options, diffrent usb port options

anyway back to the point (or [/rant] how do you feel about what has been said and can anyone offer me an opinion, in terms of echonomics putting the stuff that can be changed in the keyboard/battery part means a cheaper cpu board as more of them are identical (ie non need to maintain diffrent models) which can be futher exploited by only offering it in 128MB RAM designs with wifi
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I'm digging the idea.  Personally I'd rather have the sound card built into the device itself.  Hey, I can't remember, and too damn lazy to look, has anybody suggested something similar to the OQO?

[Ferret-Simpson]

I'd also prefer the sound card to be onboard, maybe with a "Phone" microjack socket? (Nokia 32xx)

lesee. . .

Use one slim battery in the main unit, that keeps it small but gives you some power for use as a basic PDA/Phone/Whatever

Then in the Keyboard pack, have either a Universal Extended battery (3200mAh) or a bunch more Nokia/RC batteries. This pads out the keyboard so it can weigh the screen down (Otherwise the PDA would tip over) But mean that a backpack isn't required.

[Da_Blitz]

actually thats the thing i find funny, i say move the sound card around in the device and you all see at as not having a sound card in the device

by device i mean the keyboard/battery and cpu combo, i take it that you mean the cpu board as "the device"

it simmilar to pci slots, i am saying "make it a plugin card" over usb. what if there were modules in the keyboard that once the keyboard has been opened could be slotted in, you want better sound? then slap in a sound card and remove the blank out plate on the edge of the case same for a usb hub if you want more ports, just remove the blankout plate and insert a USB hub module

give it an edge connector with power, USB, i2c and perhaps another option or two and it wouldnt be to hard to make a PDA that has the IO you want.

at a minimum i think that bluetooth would be on the cpu card (screen) and perhaps go to wifi on USB in the keyboard and make it an option? the advantage is you can have diffrent types of sound cards or multiple ones and linux will work with them.

i hate to think what it would do to the thickness of the device but ill work that out once i have found a screen (5" seems to be the way to go they are easier to get a hold of)

[Da_Blitz]

sorry missed a post, no battery in the screen/cpu board, all power comes from a backpack, however there is a backpack with no keyboard that clips to the back of the screen that is only a battery for those who dont want the keyboard

there will be a super capacitor to save state but it might be a good idea to invest some time in the new upcoming init systems and help reduce boot time and just shut the thing down when you need to do a battery change, ethier that or hibernate

[Ferret-Simpson]

no battery in the screen/cpu board
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Why not?


If you can get slim, high-capacity batteries, then why not have one in the device itself? It doesn't even have to be "particularly" User replaceable, since it'll only need changing if it fails. And if you can build a PPZ in the first place, you can change a damn battery.

It means that you don't have to faff around with ANY backpacks. Same for sound. Keep it on the motherboard. I can have additional sound cards in my Desktop and Laptop, but I don't desolder the motherboard to do it.

Keep the standard stuff that most people need on the device, anything that people have some queries about, take OFF board. If you have a thin battery in the device, you don't NEED a supercap. You also don't need a battery backpack to use your PDA. And as I said, if you then want to use a keyboard, you can choose between a heavy weight PDA one, with additional power. . . or stick in a Sun Type 6 USB or an eMac Pro keyboard. Whatever.

I may, often have the fault of coming up with controversial personal needs, but to off-board the main battery and sound chip. . . ? o.O That's insane.

Sorry to rant, but that's a nuttier idea than folding chorded belkin-style rotating keyboards.

[Da_Blitz]

no offence but i see you as misintrperting alot of the stuff i have said (leave the keyboard out of this ) personally your personal needs dont bother me, alot of it has helped push the platform into somthing other than "PDA". there are a couple of unseen motivations driving this board that i have not mentioned, for example this board has 3 I2C busses but i dont intend to have I2C devices in the project but run them to headers for one of my other projects where you need 3 busses  (5 would be better)

there is good reason for splitting that way, logical design is one of them (or the zen of design). battery packs would use the same case as the keyboard, brining down the cost of such item

it allows for very easy hotswap of batteries. designing a battery holder for a removebale battery is not easy and not somthing i would look fowrd to, by making the battery unit semi self contained it allows me more internal room and to cut much neede thickness off of the design.

it also assists in heat managment. at the moment if the cpu and the battery were in the same case the battery would be over the top of ethier the bluetooth chip, power supply, cpu or wifi chip. these all generate heat. heat causes lithium battries to explode (lithium bieng the second most volitile element known to man after potassium, actually i wonder how much power you could get from a potasium battery )

it really makes changing a battery easy, just slide it off and slide a new one on.

there are problems with the design, i am aware of that. one is multiple battery packs, that would mean you would have to purchase multiple IO boards. this needs thinking i can see several solutions but each has advantags and disadvanteges

with no battery in the CPU board the thickness of the base unit is about 4mm plus lcd screen thickness (4mm) plus case (about 2 mm) for comparison i mesure the c3000 screen at 8mm and the keyboard at 18mm

the battries i am looking at are 3.6v. at the current size i am looking at they cover 2x the area of a c3000 battery and are 1/2 as thick and are 2200maH. this relates to a power rating of 7.92W which is a bit more than a Z. the reason for calculating power and not beothering with voltage and current is that i am using a power converter in this design to reduce wasted power/losses

eg if you use a normal regulater to drop 5v @ 1A to 3v @ 1A you "lose" 2W ((5V-3V)*1A) now considering that the input power is 5W and the optput power is 3W you can see a loss of 40% of the power.

now before you start looking at the Z and wondering if thats where your battery life is going let me say its more complex than that and that the Z is probelly using the same tecnique as me to get a bit of extra power.

anyway back on topic, if i can get a battery as big as the screen then i would be happy, sure it will be pushed up againston IO board that produces heat as well but at least in the event of faliure you only lose the battery pack, the risks are minimised as well by the fact that the IO board should generate less head

ethier way i think i will push for usb audio if i can get it, it means more flexibility in design. i do intend to include sound on board if i can and i bileve that there is a good chance it will be however the modular bays are somthing that could make the customisation asspect easier and alot cheaper for all of us.

i did say audio but perhaps thats a bad thing as its a feature that everyone expects to have. but wifi and to a lesser extent bluetooth may be good choses for this. GPS is another as well as supprise suppries the phone. by making the phone a module it means that the sparkfun modules make it to my "to be considered list"

might add that i bought a HP rw 6828 pda pdone. its good but the one problem i have with it is that the that the headphones jack has alot of noise from everything else on the PCB, by modulrising everything in a common bay configration it allows me te come up with better RF shielding as i only have to do it for one cage and apply it to the rest.

IO boards are designed like PCI, ie just slot in no soldering required. i was thiing between a matchbox size and a 1/2 matchbox size unit.

also want to run this by you guys because its intresting, some new phones/pdas use the usb port as the headphone jack. what do you think. is this a good idea?