There can possibly be a software problem. You can try to find out some information on the LCDC forum posted below. http://forums.lcdc.cc/ The jumper on the far left is to set the GPOs to high power which is a 12V 1A maximum output. If you set the jumper to the right your GPO is 5V 150mA maximum outp...

Make sure you have VK204-24-USB or MX5 configured in the definition file.

You are using a 12V supply, 1 resistor, and 4 LEDs. Each LED takes 2.4V across them so that makes 4*2.4=9.6V. That means 2.4V will be across the resistor. By using I=V/R=2.4V/27ohms you get aproximately 89mA. Your LEDs take 80-100mA of forward current to turn them on. By using P=VI, you get 89mA*2.4...

I duplicated your situation, but I couldn't get the same result.

You can use a 27ohm 1/2 watt resistor in series with the 4 LEDs to get your circuit working properly.

You cannot use 5 LEDs because there will also be a voltage drop across the resistor.

Unfortunately the GPO state default cannot be changed for the LK204-25. The only ones that can be changed at the moment are the USB versions. This feature was never added to this unit, and we have considered changing that option.

Looks like your display is working fine. A problem you might have is that LCDC changes the contrast to their default. Change the contrast setting on LCDC to what you desire and see if it works.

You can use 1 calculated 15ohm resistor 7.3 watt resistor or you can use 9-120ohm 1watt resistors. The 1watt resistors would need to be in series with the LEDs. Each configuration will work.

If you connect 9 of the specified LEDs in series you wouldn't be able to power them up because they take 2.4V each LED. You can power them in parallel, but you would need a high wattage resistor over 7 watts. I suggest you look for LEDs that take less power LEDs.

By using the equation P=IV you get V=2.4W/.2A = 12V. This means each fan needs to run at 12V and .2A. Each header outputs a maximum of P=12V*1000mA=12W.

There is no way to turn off the power, unless you wire up a switch to the display.

That is correct.

Your screen will be fine if you have the screen constantly moving with LCDC. What I meant by clearing the screen is clear any text or characters off the screen, not cycling the power.

The only difference between these commands is one of them saves the setting and the other one doesn't.