Here's a quicky on how to connect SED133x to controllerless LCD's.
Can i use this controllerless LCD i found?
Checklist:
- Datasheet!
- Size must not exceed 640x256, anything bigger forget it!
- Must be 4-bit (D0~D1) if you want to use SED133x
- check if it's easy to solder; FFC or small pitch solder pads can be hard.
- don't forget the DC-DC converter (negative voltage generator) for contrast control, if it ain't onboard you gotta build it
- backlight requirements; LED and CCFL are easy. EL too but those mini-inverters might be hard to source.
LCD to SED-board pin layout
As manufacturers have different naming for the pins i have collected as many as possible name variations per pin.
Code:
SED133x LCD
XD0 D0
XD1 D1
XD2 D2
XD3 D3
XSCL (CL2) CP (CP2, SHFCLK, DATA SHIFT)
LP (CL1) LP (CP1, DATA LATCH, LOAD)
WF (M) M (AC Drive signal, alternate signal) (if applicable)
YD (FLM, DIN) FLM (S, FRM, FRAME, FRAME PULSE, Scan start-up)
XD0 D0
XD1 D1
XD2 D2
XD3 D3
XSCL (CL2) CP (CP2, SHFCLK, DATA SHIFT)
LP (CL1) LP (CP1, DATA LATCH, LOAD)
WF (M) M (AC Drive signal, alternate signal) (if applicable)
YD (FLM, DIN) FLM (S, FRM, FRAME, FRAME PULSE, Scan start-up)
Some LCD's have a INH(X) or /DISPOFF pin, this one's tied to +5 normally.
Obviously you'll need to wire the voltage pins too.
Regarding the negative voltage supply for contrast control (DC-DC converter), here are some namings:
Vo=Vadj
Vlc=Vee
Vdd / Vcc=+5v
Vss=GND, GROUND
Where to buy SED133x controller boards;
Henri (if he feels like) over a LCDinfo in Finland, he's got some custom built boards for the SHARP LM32007T and OPTREX DMF50480 qVGA's.
Mark de Jong in Germany
LC-Design Germany, has higher level SED boards too, not supported by Studio but perhaps of interest for the die-hard LCD freaks. Also loads of interesting LCD related goodies.
MPI in the USA, also sells DC-DC converters
EIO in the USA
SED133x DIY schematic:
Mark de Jong provides the schematics over at his website, downloads>schaltplan/anleitung platine. You may thank Mark.
Some others are floating around on the net, give it a search. Or just check the SED datasheet for application notes.
Backlight issues
coming soon
DC-DC converters (negative voltage generators)
- A cheap solution can be found here, thanks Razor.
- Another easy one here with few components, thank Chatlie
- free of charge but untested and at own risk; your ATX powersupply has -12 on the BLUE line.
More to come
I did it! But why does it look ..crappy?
congratulations! you managed to hook up that nice big 640x200 display but lo' and behold it looks like sh*t
Here's why.
The bigger the display the more distortion you will notice. In general 320x240 is the sweet spot, and therefore the most popular.
Feel free to correct me or add your own comments.