screen input?
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screen input?
i needed just a simple lcd screen for a project. i dont need color or even alpha, but just a really simple lcd like the kind you find on graphing calculators. then i found this (http://www.newhavendisplay.com/index.ph ... cts_id=607) and it looks perfect, but before i drop a hundred bucks on it, i was just wondering. how would i output to that display? lets say i have a 320x240 array of boolean values (indicating the state of each pixel), how would i translate that into an actual image on the screen? im planning on using a PIC microcontroller to be the processor that will output to the screen. if you don't have any experience with PICs, at least tell me what sort of output format i would need. Any help at all would be much appreciated.
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OMGpedobear
- Posts: 186
- Joined: Sun Nov 29, 2009 4:56 pm
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Re: screen input?
dont plan on doing anything mroe than displaying text with a pic and a screen that size, the refresh rate will be AWFULL not a problem in some application but useless to display things like pcitures. There are also many much much much chepaer screen avaiable , check the NU electroncis website, they have one for an arduino (also works with pics) for about 15 quid.
Re: screen input?
thanks for the tip. that actually got me searching around again and i found this gold mine of electronic components: http://www.sparkfun.com/commerce/categories.php?c=147, even though you guys have probably already heard of it 
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Anyway, these two screens sparked my interest in particular: http://www.sparkfun.com/commerce/produc ... ts_id=8335 and http://www.sparkfun.com/commerce/produc ... ts_id=8490. Perhaps the latter would be ideal due to the fact that i dont exactly have the fastest of processors at my disposal. but i still have no idea what kind of output i would use. its definitely some sort of ribbon cable, so im gonna need to do a lot of soldering close together.... but i honestly have no idea where to start with programming an output. the page mentions "the HX8218A driver IC". well i googled this nothing really useful to me came up. any guidance?
.Anyway, these two screens sparked my interest in particular: http://www.sparkfun.com/commerce/produc ... ts_id=8335 and http://www.sparkfun.com/commerce/produc ... ts_id=8490. Perhaps the latter would be ideal due to the fact that i dont exactly have the fastest of processors at my disposal. but i still have no idea what kind of output i would use. its definitely some sort of ribbon cable, so im gonna need to do a lot of soldering close together.... but i honestly have no idea where to start with programming an output. the page mentions "the HX8218A driver IC". well i googled this nothing really useful to me came up. any guidance?
Re: scrhack tft lcd moduleeen input?
You won't be able to fully drive either of those with a PIC, because of memory and speed issues.
Neither of the screens' drivers contain the memory required to store an entire image, so whatever circuit you use to drive it has to have that memory and be able to access the data and put it on the port to the screen quickly enough.
If you want to play with a monochrome LCD such as that first one you linked to on newhavendisplay, you will not have that issue. The monochrome LCD is on a module which comes with a controller (usually this Epson controller is standard I think) does have built-in display RAM.. in fact it may even have a little more RAM than one screen's worth, so you can command it to do some scrolling.
The interface to the epson controller is an 8-bit data port, and a couple of extra pins, one that says whether you're giving it a command or data, and one that tells it when to read the command/data.
Then you feed it a command followed by whatever supplementary data that command might need.
It's been a while since I've messed with one of these but I think you can tell it an address to start at, and write a bunch of image data in a row and it automatically increments the address until you give it a new place to start from.. that kind of thing.
Hope I have helped in some way. There's so much more that can be said about this but I don't want to keep droning on.
Neither of the screens' drivers contain the memory required to store an entire image, so whatever circuit you use to drive it has to have that memory and be able to access the data and put it on the port to the screen quickly enough.
If you want to play with a monochrome LCD such as that first one you linked to on newhavendisplay, you will not have that issue. The monochrome LCD is on a module which comes with a controller (usually this Epson controller is standard I think) does have built-in display RAM.. in fact it may even have a little more RAM than one screen's worth, so you can command it to do some scrolling.
The interface to the epson controller is an 8-bit data port, and a couple of extra pins, one that says whether you're giving it a command or data, and one that tells it when to read the command/data.
Then you feed it a command followed by whatever supplementary data that command might need.
It's been a while since I've messed with one of these but I think you can tell it an address to start at, and write a bunch of image data in a row and it automatically increments the address until you give it a new place to start from.. that kind of thing.
Hope I have helped in some way. There's so much more that can be said about this but I don't want to keep droning on.