Howto connect a LCD via LVDS?

Started by sanzoghenzo, November 01, 2013, 07:19:19 PM

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sanzoghenzo

Hi all, I'm glad to see the community growing!
I've (momentarily) abandoned the project for which I bought my board, and I'm thinking for another use. For another DIY project I have a 13" Macbook LCD laying around, an I was wondering if I can drive it with olinuxino.
From a data sheet found on the net (not the exact model, but very close), the 30 pin connector has the following pins:
1. VSS Ground
2. VDD POWER SUPPLY +3.3V
3. VDD POWER SUPPLY +3.3V
4. VEEDID DDC 3.3V Power
5. VSYNC STV out
6. CLKEDID DDC Clock
7. DATAEDID DDC data
8. RxIN0- LVDS Differential Data INPUT (R0-R5,G0)
9. RxIN0+ LVDS Differential Data INPUT (R0-R5,G0)
10. GND Ground
11. RxIN1- LVDS Differential Data INPUT (G1-G5,B0-B1)
12. RxIN1+ LVDS Differential Data INPUT (Odd G1-G5,B0-B1)
13. GND Ground
14. RxIN2- LVDS Differential Data INPUT (B2-B5,Sync,DE)
15. RxIN2+ LVDS Differential Data INPUT (B2-B5,Sync,DE)
16. GND Ground
17. RxCLK-LVDS Differential Data INPUT
18. RxCLK+ LVDS Differential Data INPUT
19. GND Ground
20. WPN Bist
21. Vdc (1 to 6) LED Annode
22. Vdc (1 to 6) LED Annode
23. NC
24. Vdc1 LED Cathode
25. Vdc2 LED Cathode
26. Vdc3 LED Cathode
27. Vdc4 LED Cathode
28. Vdc5 LED Cathode
29. Vdc6 LED Cathode
30. NC

Since I'm not so good at electronics I've got some questions:
* I see that A20 has one more LVDS channel than the LCD, can I connect them directly anyway?
* How/where can I connect EDID pins? I suppose It's not a problem if I leave them not connected, but it's a nice to have feature
* Where should I connect VSYNC pin? I guess LCD_VSYNC has nothing to do with it..
* If the energy informations of the data sheet are also applicable to my LCD, there are 6 strings of 9 LEDs each, a single LED uses 3.3V 19mA, so I need a 29.7V (max 30.6V) 114mA, for a total power consumption of 3.39W. Should I use a separate power supply or can I use a step up dc-dc converter hooked to 5V? Maybe I didn't search for enough, but I can't find the maximum current that can be drawer from 5V and 3.3V pins

I would like also to connect a wacom digitizer that has USB interface (but not the physical type A port, it's the bare circuit) and needs 3.3V (no regulator). No chance to connect it to a GPIO port, right? So, if I don't want to use an external regulator, I have to use the data pins of the USB port and the 3.3V from a GPIO port.

Thanks for the attention!
Cheers from Italy