Build Your Own Linux Powered Pda Options

[Tom61]

I've had the idea about rolling my own Linux powered PDA for some time, but I've been busy with another project of mine. So, I haven't posted about this idea, but recently Da_Blitz posted:

the iMX3 is a custom PDA idea as the 2700G chip is VERY hard to get. dont want to hijack this thread anymore so if you want more info then contact me direct or make another post

Definately looking for some more info on that!

Here's some interesting ideas to get the thread started:

GumStix ( www.gumstix.com www.gumstix.org ): Very small, proprietary, stackable modules. Very hobbyist friendly, but current models are still based around the Intel PXA255.

Colibri Module : PXA270 with most of the needed chips built in, and connections for most of the rest, in a formfactor of a DDR SODIMM. Moderately hobbyist friendly, with boards only 119Euros for the 520MHz version, but with a fixed handling fee for Hardware of 100 EUR and shipping of 45 EUR. You'll want to order more than one to be price effective with this supplier.

CM-X270 Computer-On-Module: I stubbled on to this site last night. No idea about this supplier's ablity to handle hobbyists, or even the cost of the module. However, you can configure a pretty impressive COM on that page. Up to PXA270 520Mhz, 128MB of RAM, Intel 2700G with 8MB of its own RAM, audio codec, and 512 MB of NAND flash!


Take a look at the Google Ads when you do a search for 'Arm development board', as quite a few Ads hit the mark for what we would want, if they could be had cheap, and single unit quanties (which most aren't ).

[Ferret-Simpson]

The 4" CGS screen is exactly what we're looking for. . . Same screen used in the SL-6000? XD

74mhz ARM development system? Nice.

320x240 (240x320) mode could be useful for program compatibility. . .

I think it's more important to have a good 266 DDR bus than to get faster storage. The whole advantage of the iMx cpu over the phone CPU is that it has the better memory bus. With the memory bus increase from the standard 133, We should be able to get some pretty 1337 stats from GPE-SystemInfo. Because not only will the faster memory aaffect the memory RW rates, but also the Draw rates. Which will also be affected by the inbuilt 3d/2d accelerator. ^^

I've used a similar system to the trackball before, and they're pretty sweet. I always find that mini-thumbsticks are a nightmare. One point that no-one's mentioned so far: This system WILL need a vibrator. Easy enough to do. ^^ But definately required for use as a phone. Hey, if it can be done on a clie, we can. XP Stamp, wanna find a supplier for vibration units?

No puns were intended, I'm perfectly serious.

Anyone ever seen an old Pentium laptop CPU module? Those press-on sockets would be useful for linking the boards together. . . Probably better than IDE sockets.

I'd like to see 1gb in this system, but if we can get 512mb of NAND for $80, I don't see the point of having more at extra price. . . What the hell are we going to use it for? For installing software only on the Sharp Rom I've yet to beat 64MB. Although for some reason Hentged uses essentially the whole rom space? o.O Ah whatever.

40x SD cards will be pretty nifty with the full interface of the iMx31. They're slow on the earliest Zauri because they only have the basic SD card lines. Full SDIO ports are faster for plain SD, even without SDIO stacks. I think that Freescale are hoping Sony are going to notice the iMx31 when they build their next PSP. . . I mean, built in Memory Stick support? Only Sony use it!

Well, there is going to have to be at least one camera on the screen panel for the sake of the Voip. . . My thinking on it was that using a Mobile Phone type sensor, It's not going to be any taller than the screen panel would be anyway. Moving the Thumbprint sensor (I was thinking slit style too, the Pad's are too easy to hack) onto the main box isn't a disadvantage, I'm cool with your positioning. ^^

Hmm. . . Backlit keyboard would be nice, I'm thinking Nokia style? (Membrane keyboard with built in buttons, and regularly spaced leds, with the keymap being rubber and translucent. Other than backlighting, we could always frontlight it with some small white LED's mounted on the hinge casing? Whatever. I'm still impressed by Loji's glow in the dark tape. . . That would be cool if lighting becomes impractical.

Cabling to the screen. . . How does it work on the Clamshell Z's? (Guylhelm?)

Back to hardware. . . USB client seems a waste of time to me, it means sacrificing one of the three onboard USB hosts. . . (2 external, One wifi, Bluetooth on BTUART?) And with functioning bluetooth, I don;t se the point in it. . . A USB bluetooth adaptor costs somewhere in the region of $10, roughtly the same price of the Usb-Usb cable to connect the PocketPenguin via USB client.

My updated requests list.

Core System
iMx31
256mb DDR - Worth it for the number of "Out of Memory" crashes I get on my Poodle

Storage
512mb NAND flash - More is overkill with he expansion
1x EXT CF - Internal header, sure. . . But only if we're not sacrificing anything major.
2xEXT SDIO - Even if just in SD mode, this gives us alot more expansion to play with. In the unlikely event we run out of internal program storage, We can still have 1x Core SD card and a removable SD card for swapping data to a PC, other PDA, Mobile. . That kinda thing.

Wireless
Bluetooth on BTUART - Serial interface to save USB ports. Needed if only for the sake of the Bluetooth Headset.
Wifi on internal USB - USB PDA modules are lower draining than CF, and use less resources. Also means with the USB2.480 that we can have reliable 802.11G with WPA, which is pretty much a requirement for modern wifi networks, such as hotspots and secure routers.
Triband GSM with GPRS - This is a big one, since my phones are always breaking down, and don't have enough features. Quad band and W-CDMA (3G) are always good, but if modules are hard to find, I'd rather have the base capability.

User I/O:
Qwerty/Dvorak keyboard with Ctrl/Alt - Back/front lit if feasible.
Camera for Voip - One of my biggies. Will save alot of system resources over a USB webcam.
Camera for photos - Not so important to me, but always good if it's feasible.
Four way Directional pad - Definately important, How can I play Zpsx or Snes9x without it???
Trackball - Still not sure on this one, but good if it's not going to cause havok with anything else.
Touchscreen - Much more important than the trackball, because it's one of the things that can't be added externally, as well as being an important UI function. I use mine for alot of things, gaming, drawing, control of applications.
Built in speakers and microphone - It's gonna have phone support, so all the fun of bluetooth headsets not withstanding, This is important for basically Loudspeaker mode.
External Headphone/Mic sockets - This is required in some form, if we run out of space I can deal with a Nokia style 2.5mm socket, but separate 3.5mm would be better.
Vibration - For silent mode as a phone. Also good for zPSX.
Slit-Style fingerprint reader: If we can include this, it would be a very good idea. A friend has this on his ipaQ and it's the only method of login he uses. Along with an encrypted filesystem, we could have almost complete security.
EMP/Ion Cannon. - It's not possible, no no no no NO!

Other Expansion sockets
SVGA output through HDMI - Not high on my priorities, but it is for some people, and shouldn't be too hard to interface. There needs to be some sort of hardware switch to select between internal 640x480, both 640x480 and external-only 800x600.
USB2-480. 2 external, plus one wifi. Client mode is not that useful these days, if you think about it realistically, since every PC can use Bluetooth anyway if it can support the specs needed for USB client, and costs us a USB port. The one advantage of it is that it gives the option to use the PP/Z (PocketPenguin or Zaurus ) as a mass storage device, but if the OS builder adds a program in GPE or Opie to configure a basic SAMBA share (And how useful would THAT be?) The same result can be achieved over a LAN/WLAN or BPAN.
Expansion/Docking connector - This should be easy to add, and provides some good options. Instead of an internal microdrive connector, if the second ATA/CF socket lines are built into the Expansion connector then a backpack/docking station could include a hard disk, CDROM drive and second power source. We could also include one of our two external USB sockets as part of the Docking connector, Which could then link to a USB Graphics card (480mbps. . .) as well as a second keyboard/mouse.

That covers most of our basic features, and if we drop a couple of things, say USB client (Sorry Tom), an internal CF/MD (Sorry Blitz) and a secondary screen we could do it. Secondary screen. . . This is nice, but would anly really be practical on the reverse of the screen panel, to show info while the screen is closed, like a samsung mobile. . . It would be good (A screen like the Nokia 6100 screen on sparkfun would work) but would add extra depth and cabling, as well as some internal electronics. . (How do we wire two screens to one framebuffer?) and power usage (CPU has to be working harder to keep it updated.)

Looks to me like the system is heading towards a cost of about $600-$700 complete with all parts. . . That's not bad! Not THAT much more than a 3200, and is better featured. . .