How to auto-power on LCD

[gryhnd]

Perhaps my search foo is weak, but I only found one post about this and the responder took it to PM :-(

Unlike my other cabs with CRTs which always return to their previous power state when electricity is cut to them (IOW...once I turn it on, it will always turn back on when power is (re)applied), a small Viewsonic LCD I have does not do this. I was planning to use it for a bar/table top unit for my nephews, but I'm disliking the idea of having them need to push two buttons (even if only occasionally) to play the cab.

Is there an easy way to overcome this? Operative word being easy 

I imagine if I was handier with circuits I could design some sort of relay hooked to a capacitor that bled off, but I don't know enough about it to do it.

How do others handle this?

If it matters, this is a Viewsonic VG150

TIA

[Blanka]

I have had 5 types of LCD's last 2 year, and all resume to the previous state after putting the power back on. Guess you have to ditch the viewsonic.

[gryhnd]

 

Ok, I'll accept that I said "easy"...but that's one I could figure out on my own 

Not looking to do away with the monitor though. I like to recycle.

Any other suggestions that don't involve using a different monitor.

[lilshawn]

Try shutting off power to your lcd and then hold the power button and apply the power. If it operates you can just open it up and solder a wire on the power button to short it out.

Try leaving the power on. Ie plugged in and on. If you cut the video signal (turn off computer) it should shut off and go to a standby mode.

If not, consider a different monitor.

[DJ_Izumi]

...Why not use an IR blaster and just set the computer to send the 'Power On' IR command on bootup of the OS?

[MonMotha]

If just holding the button won't work, try this:

If it's a low voltage momentary pushbutton for the power (pretty common - the microcontroller inside controls the actual power supplies) you can sometimes bridge the switch terminals with a capacitor (the value you need varies with circuit topology - start with like 10uF).  The cap looks like a closed switch when power is initially applied then transitions to looking like an open switch as the cap charges up.  Basically, it looks like you pressed the switch momentarily right as power was applied to the unit.

Of course, a small micro or analog timer circuit and a transistor can also accomplish this in an even more controlled method including with an initial delay if needed to let the MCU in the micro "start up" before it looks for a power button press.  Details upon request if needed.

[gryhnd]

@LilShawn: good thought...I had tried that (should have said so initially) and no dice 

@MonMotha: that's what I was expecting might be needed. If there's no other ideas, I'll try the cap route first and see what happens.

Thanks!

[lilshawn]

I don't think that will work on a monitor, since there would be no remote control.

[Blanka]

Or program an arduino to switch it on.

[MonMotha]

Or program an arduino to switch it on.

That was my suggestion...

[kyoke]

@gryhnd: You didn't by chance figure out which wire to short on the key controller board inside your ViewSonic monitor did you? I have a ViewSonic as well that turns on the moment I press and hold the power button. It does not require releasing the power button to turn it on which I would imagine means I can solder the wire to allow it to go on the moment power is applied from the mains.

[gryhnd]

Kyoke,

No, I didn't, but that's because mine doesn't work that way.

I've tabled this project for now, but will come back around to it later. Perhaps in the Fall.

I'm actually in the early stages of a touch screen jukebox built into a (censored for now in case this doesn't come out the way I like!).  I have about 80% of the parts either already here or arriving in the next few weeks.

[kyoke]

@gryhnd: That'll be awesome to see... Antique cabinet? Built into a bar? What could it be?!?

[gryhnd]

@gryhnd: That'll be awesome to see... Antique cabinet? Built into a bar? What could it be?!?

[Thenasty]

build one of this




but have it so when you turn the CAB on, it reaches out and push the power button for you  

[Franco B]

I don't know why but the first 15 seconds of that cracks me up 

[gryhnd]

but have it so when you turn the CAB on, it reaches out and push the power button for you  

[qrz]

this should do the trick

[gryhnd]

this should do the trick