Omnimaga
General Discussion => Technology and Development => Other => Topic started by: Geekboy1011 on December 01, 2013, 12:00:28 am
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So a few months ago I had an idea I kept mostly private because I was not sure of the feasibility of it but after talking to Kerm and a few other people throughout the past 8 months I have a set of features that seems reasonable to use.
Now at this point you all have probably read the post title and wondered what I mean by "drop-in" PCB hardware mod. By this I mean a PCB that you place on top of the calculators PCB and solder plated pads directly to the calculator PCB making modding easy and with minimal fuss for anyone competent with a soldering iron.*
(*minimal fuss still requires some case redesigning to fit the new parts but should be achievable with just a pair of snips and a drill.)
Now features I want to to have in list of importance- Usb rechargable battery
- Overclock
- Calcnet usbhid/arduino adapter built in
- Back light
- Speakers
- Fancy Lights
- SD card storage for programs
Now explanations of all of this:- Rechargable battery: a to be decided on size rechargeable internal battery. need I say more? no more AAA's!!
- Overclock : I needed the pcb anchor points so why not add it its cheap!
- Calcnet/usbhid/arduino: for a handful of the features below I need some kinda auxiliary processor so I figured why not throw in an ATmega32u4 (the same processor that's in an arduino Leonard). This will be tied to the data lines on the calc and a few other items and will handle all the auxiliary hardware and computer interfacing.
- Backlight: this has always been an issue on the 83+se so the solution I have takes after the lights used on gameboy/colors/advances and installs a light rod you can position to illuminate your screen! (will probably be the hardest to install item of the mod)
- Speakers: who doesn't love sound, a pair of speakers "gutted" from phones they will be small speakers that pack a punch and are easy to install (gutted means ordered from amazon)
- Lights: who doesn't like link activity lights and lights that change colors based on the music being played I know I do!
- SD card: This is last because I just thought of it and will take a lot of work to implement software side. But would be an awesome feature.
More to add will edit this post as I find the links to the info and start sketching out things. SO what do you all think?[/list]
EDIT: Anything below this is a link dump so I can find it all later thusly it is not formatted or edited for clarity
sd http://www.digikey.com/product-detail/en/DM3CS-SF/HR1972CT-ND/2602740
el wire http://www.coolneon.com/ particularly the angelhair aqua or the HBS white
struggling issues for EL the inverter takes up a lot of space. maybe shove it behind the lcd that would free up the space needed? Possible interferance with speakers tho????
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It sounds quite awesome actually. Something you may want to think of is Keoni's soundchip. If it is possible to have it running on the Arduino and speakers then it's going to be epic.
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An SD card reader would be feasable if you put an arduino in there! It can read SD cards via SPI!
For a built in arduino you will need:
-ATmega328
-3,3v regulator
-10k resistors (?x)
-22pF capacitors (2x)
-100nF capacitor
-16MHz crystal
-maybe some other bits I forgot to mention.
As for the internal battery: a tp4056 chip can be used to charge a 3,7v lithium ion battery! You'd need to step up the voltage to 5V in order to make the calculator work though.
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iirc the inside of the calculator is already regulated at 3.3v, so you won't need an extra regulator for the arduino. You might need a new voltage regulator for the lithium battery though, because I don't think the default regulator will work well with a 3.7v battery.
BTW: Will you be able to use the arduino to run costom code, as a 2nd CPU? Or is it basically a calcnet/sound card?
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The tp4056 does that.
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Thanks for the feedback! i plan on making sure the arduino is reporgramable so technically you could make it do what ever you want but for the first couple attempts on this it will be specific functions only.
@soundchip depends on how much room we have to spare we have very limited space and i have to include a few user accesable buttons/switches still.
Looking into the battery part of things again i originally intended to use a buckboost charger/converter for the arduino and calculator power. my only fear is a lower capacity battery will run out quickly depending on whats going on.
I have a lot of features i want to include with the sdcard and i will be putting it into teh schematic soon as time allows. mostly i want it to remove the need for a link cable and with a custom application be able to browse the sd card and interface with it and send programs using the standard ti link protocol instead of a custom one. so that multipage apps and the works actually can be sent. for extra storage space and all that. I also plan on making stuff exportable to the card but that's last on the list as if its not completed its not the end of the world its still a feasible mod!
@ben_G the arduino will be running off a converter and not the calculators internal for a couple reasons mostly having todo with being able to reset it with out mucking up anything but the arduino.
*searches the tp4056
also anyone have a good source of LiPo/Li-Ion batteries let me know ive had trouble speccing them in the past.
also if this works and is easy enough to assemble I plan on making it available/offering install services because why the hell not!
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This looks like a pretty awesome project Geekboy! :D
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Thanks art its been fun the entire time ive had it in my head ive gone through 4 or 5 feature revisions. I've talked with KermM about the feasibility of a lot of it and its been worked down to what I feel is the most bang for the $ and the middle range of hard to implement. This is also my first adventure into SMC soldering and product installation. So hopefully it goes as plan! will be awesome if it does. And as long as I have support, Motivation, and people helping me on stuff I don't know it should work out!!!!
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The soundchip is a program that runs on an arduino, so you can make it multifunctional. The link protocol I use for the soundchip is not great, so there is definitely room for improvement there.
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we could work on that if you would like ^^ I really just need the arduino to work as a control board to change the settings on various lines to control if the speakers are attached or if the lights are on ect. everything after that is an addon.
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Interesting. What would definitively be nice is a switch allowing you to change the clock speed or a mod plus an OS change letting you change the speed. SD card storage is definitively great as well. :)
With all the changes you are applying, good luck fitting everything in and not accidentally anything, though. >.<
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I plan on making an application that will interface with the arduino to control all the settings. The over clock portions will be an os mod tho and not me this mod specific. We are just going to abuse the link protocol and have the arduino speak the ti link protocol and be able to configure everything that way
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I'd love to contribut to this project actually. Also it should be made so that the built in light rod is optional for people who want to make their own screen light (EL backlight, GBA SP diffuser, etc.).
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It's planned to be totally modular the reason I'm going for the light rod is I have personally tried a few back lighting methods they all sucked I mean I have a few more to try first but a form of light rod is indeed the best solution I have found.
As for help finding parts and support are really all I need right now. I can do most of this on my own long as I stay motivated so keep up the good work ;)
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By "GBA SP diffuser by the way, I meant this :
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This sounds like an awesome project, keep up the great work! O.O
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Links to any documentation on that would be wonderful. That seems awesome!
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Well there's a link in the description. It uses the frontlight from the majority of the GBA SP.
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I'm on my phone that's why I didn't see it lol
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So this is what i was thinking about LED light bar
(https://dl.dropboxusercontent.com/u/98196116/ti83%2Bselightbar%20mod.png)
Just a small rob embedded on the side of the screen that you pick up(well push on the bottom of in this case) and it shines A light onto the screen. Will look a lot more professional then the screenshot of course ^^
Note the rod is embedded in the screen so its flush I just messed up the drawing.
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On that SD card, if you avoid implementing a filesystem you could do it a lot more easily. Since you have USBHID anyway, why not just make it completely internal? Then you can just treat it as extra Flash.
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because thats In my opinion more work. I Can have the arduino handle all the file system jargon and pass info back via the ti-link protocol or calcnet depending on what the scenario is. that is in my honest opinion easier.
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That's probably true thanks to FAT libs for the arduino. Coding a FAT driver would push it over the edge, though.
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I also have the thought to use cn2 to make more storage accessible via the arduino and SD card by allowing arbitrary file writing.
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It would be awesome if you could handle the sd card as internal flash, and that you can make it possible for applications to run from it (witouth needing a transfer), but I don't know if this is even possible because of the different types of flash.
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No you cannot execute from an sd card. You'd have to load the data to ram first.
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In theory I could write a shell that would copy the data from the SD card to ram and run it. Will I want to do that. No. Will I post enough documentation on how so someone else can. Yes. Will I be very happy if someone did yes. Because in all honesty I expect my self to write a self contained calcnet stub on the arduino chip that will allow you to interface with the SD card directly over calcnet. which means all you need to do is pass information to the arduino via a specific pattern/form and it will send the proper information back. I need to talk to KermM about the feasibility of this tho because it would have to abuse Calculator Id's as command codes to help make it as efficient as possible but it should be doable. (this is read I'm afraid of running out of space on the micro controller it self...i wonder if there is a library to load binary blobs off the sd card or something...)
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So I have been working on the schematic slowly and surely. But I am kinda at a crucial decision making portion of this project. That is what battery do we want to use. I'm trying to balance size+capacity+price. I pretty much need help finding a good place to source these. I will be looking at digikey and mouser. But for anything other then discretes they have been seemingly pricey to me.
I will report back soon with the space we have on the high end to fit the circuitry and the battery in.
Seems to be 2"x1.5"x1/4" space for the battery or smaller. Hope we can find something that fits. And the height is an estimate there might be a little more or a little less then a 1/4" I am honestly not to sure based on pcb layout and such we can fudge it a little tho
Digikey had nothing that would work nor did mouser. Any suggestions on where else to search?
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http://www.alibaba.com/
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I am currently looking at using an old phone battery. I feel it's going to be more reliable then anything I can find on alibaba :p
Cross post from Cemetech
http://www.ebay.com/itm/OEM-MOTOROLA-SNN5794A-Battery-RAZR-V3-V3a-V3C-V3M-780-mAh-/161119556525
Thinking of using this as the battery for this project. It has a rating of 180mAh and Preliminary maths show that the run time should be suitable for use in this application(upwards of 16 hours screen on time on normal/moderate load) . It brings up a small side project with it though, There are 4 pins on the battery and we think 2 of them are I2C lines. So we are going to probe them to see what we can get back from them!
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I was actually thinking a phone battery or something similar might be the way to to. Some cameras have pretty small lithium ion rechargeable battery packs as well. Also, what about the GBA SP or Nintendo DS? Those batteries might be worth checking into as well, though I am unsure of the size.
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I have one of those from my broken ds. I will look up the pinout and see if I can put it to use.
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They are marked +/- and that's it! Nice and easy I like that idea to.
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Just avoid the older iPhone batteries, since they seem to have an history of expanding or exploding. But choose one that isn't too expensive either.
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The ds one is about 9$ for an official one and the nockoffs are about 3-4$ so cheap enough by my standards!
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Got the start of a schematic going not sure if its all done right. Can someone check my math/configurations for me. I can answer questions as needed. Just do not want to fab the board and lose the money if its wrong.
(https://dl.dropboxusercontent.com/u/98196116/DPPCBV1R1a.png)
Edit Sorunome: resized image
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I built an ATmega328 in my calculator once and the reset line was tied to the ON button. It works fine.
How are you going to wire up the usb? You cannot put more than two devices on the serial bus.
I assume you pulled the charger and regulator circuits from the datasheet of those IC's, so I can safely assume those are allright. I'd make a prototype first before you order a pcb. With some smd prototyping board you could maybe even fit it inside a calculator.
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for 3 of the pcb's its only like 15$ which really isn't that expensive i actually think the prototyping board is more costly.
I am also using the atmega32u4 which is the device in the arduino leonardo. Which has a built in usb slave controller so no VUSB good proper usb <333
Any tying it to the on button wont work for this instance as the on key is used to arbitrate things in cn2 programs but I like that idea for a normal project!
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So, how are you planning on connecting both the calculator and the microcontroller to the same usb port??
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They are not thats the trick. The calculator is connected to the atemga via its link port then the arduino acts as the usb device. With some code the arduino acts as one of a few things, In this case they are a silverlink and a GCN hub. The usb also charges the battery that is powering everything. So yeah.
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So that leaves you with a spare connector at the back of the calc: the linkport. You can hook up sound output to that for example :D
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That' has been the intention, I plan on putting a low powered speaker built inside the case of mine at least. Just to be able to say hey I want music!
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*bump* Any progress?
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Yeah, I wonder too since I'm also interested in this mod. :)
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Esp. because of the atmega inside. If enough people install one of these in their calc I plan to port TIMID to this chip.
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Oh true, that does sound like a lot of fun. :D
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As of the current point in time. Yeah nothing >.< And i might be changing SOCs to something a little more fun if i continue this. Go look up the spark photon :D that being said this is still on my todo list i just have not had time for it at all and when i finnally get time again i will be working on this project with lots of interest
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Wow that mcu looks pretty cool. Better than an arduino, same price. The choice is pretty quick (well the rpi model a+ is even better but no built in wifi and it's larger so it depends on what you do with it).
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Yeah I would be using the PO which is even nicer. And with all this well wifi enabled linking anyone :D and many other features that i would have had to kludge in to begin with. The only thing it doesn't support out of the box is usb iirc. But i have to look into that.
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I am not sure if I'll be able to port TIMID to that though...
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Who needs USB ? Just add support for this in libticables and transfer files over wifi ! :D