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Comment by robertely | Hacker News Reader

[Author] The premium was mostly Adafruit markup and convenience. I'm totally not mad at the price, I received parts next day. If I really wanted to save money I would design an adapter board, and order bulk screens from China.

Keep in mind this is prototype cost, typically inflated seriously because it's a one off.

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How does this compare with some the Raspberry Pi screen kits from China?

I see you can get a generic Pi LCD for $7.65, a 5" LCD with video in for $18.75, and a touchscreen Pi size kit for $19.90[1].

Going to the effort of breaking out DPI through the GPIO was quite creative. If optimized do you think these can hit sub $5? Either way, this was very clever. Thank you for taking the time to document this for others!

[1] http://www.aliexpress.com/wholesale?catId=0&initiative_id=SB...

So, these are almost all crappy clones of this: http://www.adafruit.com/products/1601 It's fine for static images and low quality video, but its using the SPI bus and a custom driver. This severely limits size of the display and/or refresh rate.

Yeah. This might change if the Chinese companies get wind of this technique; if I recall correctly these kinds of parallel LCD panels aren't all that expensive. (Edit: Actually, the controller chip used in those existing Pi LCD modules seems to support the required interface, it's just not pinned out. They could probably make new versions of the modules that are wired up properly.)

there is no controller needed, every single laptop LCD panel from ~10 years old was parallel. Then we got LVDS. Laptop screens from ~7(?) years ago have LVDS deserializer chip on the Tcon pcb (DS90C562/SN75LVDS86), you can desolder that and connect directly to parallel bus. Never screens integrated Flatlink(lvds) receiver inside main lcd driver chip.

LVDS is just serialized parallel video. Serializer chips are ~$5 in singles on Mouser. Combining Pee DPI output with SN75LVDS84 ($2.5 if you order 10 from china) will allow you to connect any modern <=1366x768 resolution (single lvds channel limit) Laptop LCD screen. Those can be free if you have a broken laptop. You could even drive older "HDReady" 32' TV LCD with pee this way.

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