Hi Patrick, there’s a good chance that you need to find an LCD that has the same connections / controls / controller that the GHI ones use, unless you’re up for some heavier duty work on drivers, so that’s the first suggestion I’d make, look at what their hardware is and see if you can locate compatibble stuff, if you dont think their hardware will suit your need?
That is how ever not the problem, I have the Fez Cobra and connected a 5.0" 800x480 TFT screen from Tianme to it, also an 4.3" 480x272 from Sharp and a 5.7" 640x480 from OSD and all worked fine.On the EMX is an LPC2478 microcontroller and all you must do is give the right spec’s from the TFT screen, like vsync pluse widht, hsync pulse width etc.
Look at the example code:
static bool SetLCDConfiguration()
Configuration.LCD.Configurations lcdConfig = new Configuration.LCD.Configurations();
//Stel variabelen in van lcdConfig
lcdConfig.Width = 800; //Breedte
lcdConfig.Height = 480; //Hoogte
lcdConfig.PriorityEnable = true; //Geef interne LCD controller hoogste prioriteit
lcdConfig.OutputEnableIsFixed = false; //true if LCD enable is a fixed state. false if LCD enable is managed by LCD controller.
lcdConfig.OutputEnablePolarity = true; //true if active state is high.
lcdConfig.PixelPolarity = true; //true if your LCD clocks data on the rising edge of the LCD clock.
lcdConfig.HorizontalSyncPolarity = false; //true if active state is high.
lcdConfig.VerticalSyncPolarity = false; //true if active state is high.
lcdConfig.HorizontalSyncPulseWidth = 1;
lcdConfig.HorizontalBackPorch = 88;
lcdConfig.HorizontalFrontPorch = 1;
lcdConfig.VerticalSyncPulseWidth = 3;
lcdConfig.VerticalBackPorch = 32;
lcdConfig.VerticalFrontPorch = 1;
lcdConfig.PixelClockDivider = 3; //72Mhz / 8 is = Mhz
I assume the same idea is used in the G120 module.
The only problem is that the LPC2478 is not fast enough for the 800x480 screen. It will give an picture, but when using the sd card, the DMA channel is used and the picture will be strange.
I tought if I can make an module with all on it, it will be for the people a very nice solution. The only have to buy one module with all on it, and can start right away or use in of there project without making an lcd board or something else.
3.5" I believe is the sweet spot for cost, I believe. The one major drawback of the 7" is that I have to decide between it and a Nexus 7, and there’s no contest there. If a 3.5" screen could be had cheaply, I’d start there.
The TFT screen must not be expensive, because the project must be interesting for starters, hobby and for the business.
I tought not to use an 3.5" screen, because this one is already in the shop of GHI.
It will be one module, so TFT screen with a PCB on the backside. On the PCB the G120 is present. Also it is possible to solder the Wifi module on it. It will have an micro sd card and a micro usb socket onboard. The last one has the advanced that with a cheap adapter cable an normal USB stick can be connected to it.
You also have an display with 4.3" and 480x800 with an capacitive touch on it, it is from Truly TFT modules, offcourse the resolution is big, but with my Fez Cobra i can run an 800x480 5.0" screen.