Coding under Android

Hi,

Well, I've been stymied trying to find 4-5" 4:3 LCD touch panels (I did find a nice one at 5" but have yet to chase down the manufacturer for availability).

Rather than wait, I am begrudgingly looking at a cheap ($50)

7" tablet to advance a bit further towards a real "beta".

Tablet runs Android. So, I can either figure out how to root the thing (and then hope I can find docs on the various bits of hardware inside) *or* build an emulation system *under* Android to give me the environment I want.

The latter is less "run-time" efficient but may be a better short-term bet to get further along with testing.

Also, I need a tablet-like device for another application (though 7" is awfully large :< ).

So, how responsive is Android? How rich is the programming model (flat address space? protection domains? VMM? etc.)? What are the *gripes* about it? And, reasons for each "point release" (i.e., are they fixing bugs or fixing "missing features")?

Thx,

--don

Reply to
Don Y
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Some are easier to root than others. Some even support rooted device officially. Just ask them.

It's Linux 2.6 kernel. Each process has linear virtual address space.

Some are difficult to root. Even so, we got something working on unrooted droid via Android Debug Bridge over USB.

Android Development tool kits are different. But then, we go straight with C anyway.

Reply to
linnix

I'm looking at some of the no-name Chinese devices. Can't afford to shell out 10 x hundreds of dollars for "name brand" -- especially when all I *really* want is the display+touch panel.

That's *all*? I thought android was something new from scratch...

But, that's a consequence of the particular implementation, not Android itself. I want to know why I might want to

*avoid* an Android platform (assume it was "open")
Reply to
Don Y

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The user layers is totally different (but not new) from MS or X, but the kernel is fairly standard.

Our reason to root it is to start a custom layer, and avoiding the GUI. Why bother with G when we don't have much UI interactions. However, your situation might be different.

Reply to
linnix

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Well... performance for certain applications are pretty lacking since when programming an Android app you are limited to java and the Android SDK. There does exist the NDK for more performance critical applications... but it seems like a pain to use. For example, look at the state of computer vision or even just imaging algorithms on Android... pretty abysmal. Whereas you could get much better results if you could just have the ability to code the thing in C.

Now that I think about it... if you have root maybe there is a way to get some un-authorized native code running? I personally haven't tried that.

With Android you are buying into the UI for the form factor. Getting "support" for Android or the SoC specific kernel might be pretty lacking as well (source is really fragmented, the last android or kernel for that device, if any have existed before, might be really old...) I would look at just putting on a regular GNU/Linux install on the device if you want more control and performance and the end use doesn't _have_ to be Android. Linaro.org might be of interest?

So what are you really using it for? You do know that the SDK and tools already provide an emulator right?

Reply to
Bryan Buckley
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You *can't*? If it's the "Linux 2.6 kernel", then are you saying the kernel interfaces are *hidden*?

I get nervous with the "chinese garage shops" (even if they are multimillion dollar organizations!)

Ideally, give me an X server and a means to export access to the various devices on the box and I should be able to do what I want. And/or a means of loading (smallish) applications/services into RAM (so I can alter the device's characteristics)

Reply to
Don Y

"Applications" are supposed to be written in Java, for portability and security. Native development is intended for hardware vendors, not third-party "app" developers. Access to the lower levels depends upon how locked-down a particular model is. If the vendor is selling the hardware at (or below) cost, with the intention of making their profit on services and add-ons, they're going to try to keep you locked into their ecosystem.

Reply to
Nobody

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That seems to be the trend, everybody wants to sell you a TV set. You are supposed to use the remote, no more. Which can also be an opportunity to some of us, of course.

Dimiter

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Reply to
dp

I don't think that reasoning applies to the chinese knock-offs. They just want to undercut the "mainstream" sellers.

Reply to
Don Y

I think that's also what *customers* want. They don't want to understand their products... just *use* them.

I'm embarassed at the number of "broken" items folks give me (knowing I can either fix or salvage something from them). After investing some time trying to figure out *what* is broken, I'll approach the donor to *ask* what was wrong and I'll get a dubious reply. If I press the issue, it often resolves to: "Oh, we just wanted to get a newer model..."

So, now they've handed off their responsibility for figuring out what to do with the device to *me*! :-/

[P.S. I'll have updated pix for you, soon. Lots of progress, here! Yay!]
Reply to
Don Y

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Yes, you can. We are running native C program on Android 2.1 via ADK. The only problem is that we can't start it in init script without rooting it. In theory, we can run a custom window manager on the hardware itself. Afterall, it's just Video4Linux.

Not if you know what you are doing. May I ask people to google or do it before making informed opinions.

.

That's why there is a better chance of "rooting" a no-name chinese model. Don't get it from phone companies.

Reply to
linnix

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Hi Don, yes, of course that is the underlying reason. But I would not underestimate the "public", they just consume what is available, it is hard to say which is cause and which is effect on that. Anyway, too busy at the moment to do more than idle thinking on the "opportunity" :-).

Dimiter

Reply to
dp

Ah, OK. Init starts some java-oriented "shell"?

*Really*? I figured buying one of these was "you're on your own!"

Is there a high degree of similarity between products that makes this possible? Or, do you have to hope to find someone who has already done some/all of the work on your *particular* model?

(I don't put much faith in the "model numbers" on much of this knockoff stuff... sort of like buying Rollex [sic} watches!)

Reply to
Don Y

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Just download the Android source and start exploring.

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In my experience you are correct in assuming you are "on your own." There are some devices that have a lot of people in the community getting the hardware working with more recent software (Pandaboard, beagleboard, newer phones..) Devices that you buy have software that is usually forked at a specfic release (from Google and SoC maker) and further developed by the person selling you the device. You are lucky if there is an effort to keep refreshing the SW.

Sure rooting a no-name device might be easier... reason being is the bootloader is locked down!!! But what kind of resources will you have with the device support in SW...

Reply to
Bryan Buckley

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Yes, all we need is to change it to start our own. Alternatively, we use a micro with USB Android Debug Bridge to start it.

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But it's better than buying from the phone company whose main purpose is to hide everything from you.

Reply to
linnix

Don - rather than end up with a load of stuff you don't want take a look at the Noritake Itron ISmart TFT modules -

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The look pretty good value for money - I haven't tried them (and have no connection with them) but I have them on my list for the next time I need a little LCD display.

Michael Kellett

Reply to
mk

That;s exactly what's wrong with most OSS: you're just left poking around without a roadmap or any framework that tells you what you might find -- and *where*. No whitepapers, no specifications... you're lucky if you get a breakdown of the "source tree" (which is often of little value as the directory names give about the same amount of information!)

I am not concerned with folks keeping "-current". Rather, I'm concerned about finding the information I need to "go my own way". E.g., you don't care if an SBC manufacturer keeps his "BIOS" current -- esp if you aren't planning on running "DOS" on that platform!

All I need to know is which devices are "where" in the memory map (and, documentation for the chipset(s) used). Since these devices tend to be pretty densely populated, probing theboard is usually impractical. But, inspecting *some* sources (device drivers) would give a clue as to how things are wired -- if the chipset docs are forthcoming.

Reply to
Don Y

Not looking at *phones* (but I understand your point)

Reply to
Don Y

Interesting devices. A bit pricey in small quantities (e.g., ~100-150USD). Aside from that, the two immediate impediments are:

- "Not currently available for sale or use in Asia or North America"

- "One Time Entry - Contact Details"

(you know, when I go to buy a *car*, they don't insist on having my name, address and email before they'll let me peek under the hood... if they *do*, I know its because they want to later HARASS ME)

I'll bookmark the page, though, for future reference. But, I think pursuing the android tablet is probably my better option at this point. Unfortunately, it looks like I'll need to research "popularity" instead of just *features* (in the hope of finding something that is "well exposed")

Reply to
Don Y

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These VIA tablet seems pretty good, around $80 including shipping to the US. It's a 800MHz ARM9 based processor.

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Reply to
linnix

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