Propeller Handheld Unit aka Propheld

jaeg

Hi, I've been trying to figure out exactly what I want to do with my LCD touchscreen from Rayman and I think I have come up with the answer. I call it Propheld. It's a multipurpose Propeller system that is mostly geared towards gaming. I've attached a design document that I came up with. Please tell me what you think. Any noticeable flaws? Any ideas?

I've tried keeping it as simple as possible so other people can build one too. I'm not entirely certain if I want to keep the Gameboy Advanced/DS style layout or go with a Gameboy Color type layout yet.

Edit - OH how cool... Scroll all the way down and there is a similar threads box. That's nifty.

Edit 2 - Changed some things on the design documents. Added an OS section, mentioned possibility of 2nd multiplexer. Added 1k resistors to list to protect the Propeller from the multiplexers 5v logic, Changed how the pins are arranged.

Rayman

Sound great to me We really need a case for these 3.5" displays...

I'm hoping Chuck George at MountainKingTech will come up with something for us...

jaeg

I think mines your 4.3" display. My plan is to use something similar to those clips used to keep the back pane of a picture frame on. Unless there is a better way to keep the screen in place? Maybe a slight pressure fit using something with traction like rubber lining an indentation the shape of the screen. Have a place in the back of it for the cable to go through.

Not really sure how I'm going to do that yet.

Thanks for your feedback.

Rayman

Oh, right, sorry. Actually, Chuck does have an enclosure for the PSB that you could probably use...

jaeg

Cool Does he have a website? EDIT Nevermind I found it. lol

I also noticed that the multiplexer only needs 4 pins instead of 5 so I can probably squeeze in two multiplexers giving me more inputs allowing me to use the accelerometer, mic, and still have more inputs left. I'm not sure yet.

AndreL

I am working on something very similar, "propgear" was one of the names, but I think I am going to call it the HYDRA MOBILE XTREME - "HMX" for short. Been designing it for the past 2-3 months, design is all done, prototyping now... so hopefully our products are not too similar I won't be releasing info about mine until its done as usual though --

Andre'

jaeg

I'm not selling mine. It's for personal use. I'm just documenting it so people can build there own. I'll be releasing any software I right too. Good luck with yours.

AndreL

How do you plan to make the enclosure -- injection molding such a low number of units would be costly, so I am not sure if I will add one, or maybe try a vacuum formed system -- but, are you thinking of having people rip old GBAs and put it into that?

Andre'

jaeg

I'm not sure how I'll make the enclosure. Probably just a small plastic box from Radio Shack. Or maybe just make it from plexiglass. Nothing fancy.

WBA Consulting

I have a half built portable prop gamer that is basically the heart of the hydra in a portable fashion. It uses the Propeller Platform board, Nitemax's 2.5" display, an Energizer digital picture frame battery pack, and a polycase AG-54 enclosure. The "joystick" is homebrew with a 5 position switch, 2 buttons, and the 4013 chip. It has been half built for 5 months now............:mad:

I would love to do the same thing with one of my 4.3" touch screens because the 2.5" screen and driver board take up a lot of room.

jaeg

That's what's nice about the 4.3" module. The board is very small which will make it easy to enclose along with the Gadget Gangster board add two small boards to the sides for the input buttons and presto!

AndreL

Hmmm -- on my system, I am going the other way a little bit SMALLER is better So, I am using a small screen, I am going for really tiny micro sized stuff.

Anyway, the key like anything is to add a bunch of stuff, so these systems are more interesting...

Andre'

jaeg

Oh very much so. If I add two multiplexers using 4 pins each providing 8 inputs I could affectively add 8 inputs I didn't have before that's enough for the input and a possible external sensor interface. Wouldn't be cool to measure CO2, CO, and various other things just because you can? Haha

EDIT - Edited 1st post and reuploaded updated design document

jaeg

I have made a lot of progress today on the Propheld. I don't think I like the name Propheld. Sounds cheesy. Oh well... offtopic. Anyway, the layout has changed to look more like a Gameboy with start and select buttons. All the buttons have been installed and hooked up to the multiplexer. I've fitted everything together to make sure it all fits and it does. Very tight though. The slot for the screen cable to go through has been made and it is basically finished hardwarewise.

I'm going to test the multiplexer tomorrow on my Basic Stamp to make sure it works before I hook it to my Propeller. I'll post pictures tomorrow.

jaeg

I have a question. The multiplexer chip normally operates at 5v do you think I can get away with 3.3v? I'm worried that its output to the Prop might damage the prop. I have it going through a 15k resister but the voltage I'm reading coming from the output is still about 4.8v.

I'd also like to know if there is a safe way to test out the LCD touchscreen module. I'm unsure if it was damaged or not and didn't want to risk it damaging something itself?