Hi,
I am looking for advice on a science project. I am planning on having some sort of input device in my room, probably a simple keypad that sends a signal when one of the buttons is pressed to a led matrix or screen (the sharp tft lcd from the playstation portable for example) outside my door, so when my parents knock, i can send one of a few set messages/ symbols to them, these would be from a set of 6 or 8 jpeg or bitmaps stored in memory, each one assigned to one of the imput keys.
So I need to be able to have a chip with memory big enough to store a few images and the ability to transmit the images via wire (or possibly in the future via bluetooth) when a certain key is pressed. The ability to be able to periodically reassign different images to the keys by pluging back into my pc would also be good but not essential.
From internet research, I think I would be able to put this together using arduino but am not quite sure as all the similar looking projects I've found utilise 8 by 8 led's where the image is effectively programmed directly onto the screen rather than displaying a pre-saved image.
My main question is can arduino do this? And if so, which kit would be the best to get? I can order on the internet and do the planning/ programming stage while it's being mailed. If arduino isn't the most suitable kit for this, could someone point me in the right direction?
My parents will pay any reasonable amount for the kit I need (as it's for school ) but I don't want to break the bank so any advice on where to order the kit from would be cool.
Does my plan sound possible? I have a little basic programming experience and have played around with simple circuits before, so does this sound like a reasonable project?
An Arduino does not have enough memory to store images. It can, though, interface with SD cards that can hold images. There are libraries that interface with the SD card, and can send bitmap images to an LCD screen.
The SD card could then be inserted into a reader attached to the PC to add new images.
Sparkfun has 4x3 keypads that can be used with the Arduino.
An Arduino, LCD screen, SD reader, and keypad can be had for under $100. All the stuff is available in may places. I like http://www.Sparkfun.com, but, depending on where you are, other vendors might be better choices.
Be advised, though, that this is an ambitious project. Doing the coding while waiting for the hardware to arrive is not going to be possible.
If you are ok with a 64 x 128 Graphical LCD panel and black and white images, you can easily store 8 or more full screen images in program memory on an Arduino Duemilanove without needing an SD card.
jonn,
Check Amazon for: Axion AXN-9905 9-Inch LCD Digital Picture Frame $52.
Has a remote control.
Oh wait! You wanted to build it.
keypad that sends a signal
So you are also looking to make this a remote controlled application? If so, you've got to decide where to put the Arduino... in handheld remote or on the door device, or both. Remotes (Tx/Rx pairs) can be 'simple' toggle or momentary On/Off, or can be more involved types (e.g. BT, xbee) sending encoded pulses or serial data streams... have protocols to follow.
I'm suggesting you don't need to "send the image" across the room. Just send control signals. (unless of course you really want to master that skillset for your project)
PaulS said:
Be advised, though, that this is an ambitious project.
Could be an understatement.
image is effectively programmed directly onto the screen --- rather than displaying a pre-saved image.
Yes, you'll have to decide what is most interesting or important for you to learn. And factor-in your due date.
Another option here is to buy one of those cheap MP4 players that plug into a car's 12V lighter socket. Figure a way to hack the navigation buttons using Arduino to 'close the switch'. Problem with this is that there is likely no example for it to-date and you would be encountering a bunch of unknowns yourself. And you'd miss out on learning to manipulate LCDs.