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Picked up a pico projector for dirt cheap that only supports Apple phones with a 30 pin dock connector. Lets see if I can make it do my bidding. Wahahaha!
For those interested here’s the main IC datasheet:
hey there YouTube this SJM four through six and sorry for the hand-holding not having a fixed camera or anything I'm gonna have to do this one-handed but basically I got a new toy in I got this uber cheap it's in many many pieces right now and this is a I peek oh the FL Coast projector a ferret or was it for a magnetic liquid crystalline silicon reflective projector and you can see here works I'll show you the flash screen it looks very nice this is an RGB projector so my eyes are particularly sensitive if I move my my eyes a little bit I can see kind of stripes of red green and blue you can kind of see as I move from my finger across it's flickering a little bit but anyway I just want to show you what I've been doing with it so I packed this originally this is only compatible with newer iPhones not the ones with the original 30-pin dock connector so this is the actual attachment as well as some ipod touches but not all and that's sort of a pain because this is actually pretty decent projector it's I think 940 by 950 something by 840 resolution so that's actually pretty good brightness is about I think 15 lumens but the thing is like no one has you know these iPods really didn't you know no one really cares about older iPods or whatever that this is compatible with and so these are going over cheap I got this guy for 20 bucks for a projector with the specifications that it has that's really cheap I've noticed though that as soon as I bought it prices jumped up to about 50 so you know your mallet mileage may vary but I want to show you what I've been doing so to test it I have this Arduino here programmed with a game of asteroids and so if I connect it in there and reboot this guy hopefully it'll come up yeah okay doing this one hand it is a pain okay ah I'm an idiot that's why okay right wire would help so you can see here projecting on my wall works I can hit the fire button there and it starts right up works pretty well anyway uh so yeah this is the projector so right now this is actually a composite video input so as I said it only works through this stupid little dock connector thing originally there's no other video input and I bought this with the risk that maybe the iPhone was using some kind of proprietary digital input and that might be the case looking at the number of contacts on this connector however the chip the onboard ship I downloaded the data sheet here it's the tw8 835 and I have the full datasheet here there's an embedded processor inside the the video controller chip and yeah it's this guy right here which is on the underside of the projector itself you shut this off so I've been slowly you know reverse engineering trying to get this to work so all I ended up doing was Y in 0 pin 15 here I started a wire and that wire goes to here which is a composite input now the Arduino outputs a composite video source so it's simple black and white there's no color nothing like that there'd be a little bit to grunting for this 328 processor so right now I'm just inputting that directly into the chip and luckily the configuration for this ship I assume I tried to reverse-engineer the configuration data but I'm assuming that its initial eyes to mostly default value since there's not too much data being sent into the chip this little chip here is a pic18 F rather LF the low-voltage version and this is the main controller which sends configuration data to to the video IC which then sends the data to the the actual like host panel so from what I've been able to gather is it it all did auto detects the composite input so that's why you can see the image and this works perfectly for black and white video however when I try to input some colored video it just shows up as black and white and not very stable so I'm thinking that it might be defaulting to some kind of s-video not sure exactly why but in which case if you look through the datasheet the Y and 0 for s videos luma and chroma I think is maybe C and 0 or something like that so I still have to debug this but it works for black and white video I just got to get it working for color video obviously so in order to do that I tapped off soldered tiny little wires to the I squared seat port because this chip is I squared C controllable I tapped that off it was easier to tap it off at the the pic chip there and using a logic analyzer so lay logic I get this theta here and so I'm using the I squared C analyzer and trying to make heads or tails of what the heck this guy sending this data sheet that I got for the video IC chip isn't very clear I haven't been able to find where it says what the the slave addresses so it's making a little bit confusing because I can see it's writing the pic is writing to address xx and then later on it's reading from address 21 but the data that it's reading and trying to write to when I scroll through this data sheet there's a register listing and it's not really matching up with any of that it's not really making sense so if any of you have some experience I can upload this data and maybe you can help out I mean I'm I'm pretty sure I can figure this out I just need time which is pretty much the main problem but yeah this guy is a tiny projector that's the entire optical element right there I already took it apart just to see how everything fit together and the main board's tiny so if I can get this working with the composite video that'd be great well I'm thinking is I can um I don't want to reprogram this pick I would prefer to since it uses I squared C and it has bus arbitration I can hook up another picmicro prostitute that I can program so this pick really only sends data when the device boots up so the rest of the time and I assume it's just kind of idling or doing I don't know what so what I'm thinking of doing is having a second pic that will take over the I squared C bus and send some more initialization commands for getting just standard composite input this ship also supports 24-bit digital RGB component composite s-video as well as analog RGB so I should be able to get VGA into this guy assuming the timing requirements are correct but it looks like it is which would be awesome because I can have this tiny little projector you know with nine something by 540 resolution hooked up to a computer or a Raspberry Pi or anything else yes so that'd be pretty awesome for the price of 27 bucks that's that's great just got to figure out a little nag Allah the compositing but I want to get composite working first and then I'll worry about more complex things but first things first I have to understand and decode all this nonsense once I can I can read some simple code for a pic or an hour or whatever I want just some connected to you know the I squared C lines to this ship and just send out the data and that should I should be able to externally control the chip so whatever my little heart desires so yeah this is a little update of what I've been doing more recently alongside a whole bunch of other job today besides work so yeah sorry I haven't been able to put up a video quite a while but you know it's pretty busy the semester just ended and I'm working for the summer so yeah but definitely I will spend a little bit of time getting this working this is just so freakin cool how small it is originally had a little 1500 milliamp hour battery in there but this guy is from I think 2012 and that thing was swollen like a balloon so I hastily unplugged it and tossed it you know as far away as I could for me you know lest it exploded and I'm shipping but anyway yes so I'm I'm planning on getting another lithium battery once I get all this working jackin in there removing this silly connector putting a standard composite video and put maybe a 3.5 millimeter jack and just drill a hole in the back of the case or something I already has a built-in USB for the charger for the battery so just shove another battery in there and I basically have a full-featured pico projector for 20 bucks can you believe it anyway I'll keep working on this and when I make some progress I will definitely let you guys know I'll post some updates and if anyone has some more details on this as an i pico projector maybe someone else has done this before I have no idea I looked it up online and it seems like this is an obscure device that no one has act no one's at least tried to even do anything with it so but yeah if anyone has any details or on the specific chip the TW 888 35 I definitely be appreciated that would definitely speed things along I want to I want to hack this guy and then I'll put up details online so other people can do the same thing is you can do a lot of cool projects with something like this so I want to see what people can do but first steps first let's get this thing hacked so yeah I will see you guys next time bye