If I only had a Brain!

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OK.....

P-BRAIN EMBEDDED!!!!

1st results... It works....

BUT...

Im getting a set of vertical rainbow stripes on the right side of my LCD... I probably screwed up the LCD during the embedding process...

OH Well... this is only a testbed projector anyway... There must be something up with one or more of the FFC cables...

It boots the projector and enters the Running mode, or it will enter the Fans Only On Mode when requested... but during the Running Mode when the LCD gets fired up... there are the rainbow stripes on the right side of the screen!!!! :( The vertical rainbow stripes comprise about 1/5th of the right hand side of the screen)

Oh well... at least the controller is working...

Anyone have any ideas as to why I might be getting the vertical stripes?
 
Luca Brazzi said:


Anyone have any ideas as to why I might be getting the vertical stripes?

Congrats on getting it all setup! :)

As far as the stripes go I have that too, which happened after bending the flat connectors going from the vertical controller board directly to the LCD. (Luckily I only have about 3 lines though on the very edge.) Don't think there is much you can do, unless you're very very handy soldering incredibly small things.
 
I think youre right... If I lightly rub my fingers along the flat cables that connect to the lcd underneath the section where the lines are... the lines change color/etc....

Oh well... I had already scratched the LCD way back (although it was still watchable) so Im not extremely upset about it...

Anyone know where I can get an LCD for a BENQ 567 monitor?

The important thing is that the P-Brain is working as planned.

Time to start planning Version 2....

One thing Ill need to do is either upgrade to a larger PIC or find a better way to handle some of the I/O.... Ive used up almost all of the I/O pins on the PIC16F873, and there is still funtionality I want to add that will required more I/O (Temp/Fan speed sensing/Character LCD/Serial PC Interface/etc)
 
OH BTW ...

Thanks to all those who contributed ideas and constructive criticism.

I must say this has been a fun/useful project!

My only problem now is... I wont be satisfied building a projector, without having one of these things embedded in it which will up my costs/build complexity a little but I think in the end it will be worth it. :D
 
One more pic of the P-Brain embedded after being hooked up to the projector.

Yes I know... I need to wrap those wires up a bit neater...

You can see in the pic how everything (Lamp Power/LCD Power/Fans) plug into the controller board. The Power Button, Indicator LEDs and Buzzer are mounted to the projector and visible in the upper righthand corner of the photo. For now Im going to just sit the Motion Detector on top, maybe Ill mount it somewhere later.

 
So after running with a P-Brain controlled projector for a while (yes I still watch it even though I damaged my LCD, I just have to shrink the image some so its not in the damaged part). I must say, I am happy with it (although Im probably biased since I built the thing :) ).

It works as suspected. The warning buzzer is loud enough that I can hear it even when Im in some other room in the house. Its definitely comforting knowing that the projector will take care of itself if for whatever reason I fail to take care of it. The buzzer beeps differently depending upon what timeout is about to expire... 2 quick beeps means motion is about to timeout, 3 quick beeps means Max Time On is about to timeout.

I did have one software bug though, in the booting procedure, it would sometimes detect light from the PJ Lamp, but not for long enough, so it would think the light wasnt stable when it actually was, and shut down the projector. It was an easy bug to fix, and I just plugged my pic programmer and laptop in to the p-brain and reprogrammed the chip.

One thing I have noticed though... its harder to trigger the motion detector than I originally thought. It can be done by waving an arm, but its not that easy. Its much easier to just get up... Maybe in the next version Ill implement an infrared detection input that will substitute for, or supplement, the motion detection. This way anytime it detects ANY infrared remote pulses the motion counter gets reset. That way I could just hit a remote button (any remote button) to signal "Im still here and awake" to the controller. The way Im thinking that the whole algorithm should work is:

- Any time either motion, or an infrared pulse is detected, the motion time out counter is reset.

- Any time the power button is pressed, both the motion timeout counter, and the Max Time On counter are reset

- If the p-brain is getting ready to shut down because the Max Time On timeout is about to be reached, and it detects infrared pulses or a power button press, then both the Max Time On counter and the Motion Counter are reset.

Now all I need is a good projector. My plan is to build a long throw projector using the proview 15.4" LCD and the 135mm projection lens I already have, and build it with the p-brain2 (yet to be designed and built) in mind.
 
Can you recommend a good online resource to learn PIC programming. I'm a complete noob and everything I've seen online assumes that I'm an electrical engineer. I've never seen a PIC board, I don't know how to attach things to it, I don't know how to program it... however I do know how to program, I am good with electronics, and I'm pretty intelligent so I think I could learn it if I had a good place to teach me.
 
The development environment I used was from these folks:

http://www.basicmicro.com/

See this area for a decent PIC programming development environment:

MBasic

I have the MBasic Professional package, and the ISP-Pro PIC Programmer. I used it to design/build the p-brain.

To get started PIC programming, you will need some electronics knowledge. Im not an electrical engineer, but I was an electronic technician for several years long ago before I got into software development, so I have some understanding of building/troubleshooting electronic circuits.

I didnt use a PIC board... I bought the PIC chip, and supporting components (stuff I already had lying around actually), and wired up the board myself.

If you are currently strictly into programming on PCs/Mainframes/etc, Microcontroller programming and design will open up a whole new world for you... Its alot of fun... trust me. :)
 
One more change I made...

The Beep Indicators.

Now it beeps in rapid succession...

- once for no motion about to timeout

- twice for max time on about to timeout

- three times for shutting down

I think this way is better because it conveys a sense of urgency based on what is about to happen.

If No Motion is about to timeout, I get one repeating beep, and all I have to do is trigger the motion detector

If Max time on is about to timeout, I get two repeating beeps, and I have to get up and press the power button

If the projector is shutting down, I get 3 repeating beeps, and then....well... :)

The other thing I changed was that now, the Fans on Only mode is subject to the Max Time On Timeout. Before... the fans would run indefinitely in that mode. Now, they will shut off after the max time on timeout expires. Im thinking of giving that mode its own timeout because... who would need to run their fans for 6 hours? Ive noticed that Ive been able to cool my bulb back down after being lit, to the point where it will relight within 5 minutes or so. I only use the Fans On Only mode when the projector has been on, then for whatever reason, shut down, and I want to provide extra cooling for the bulb because I want to start it back up again... Maybe Ill make the Fans On Only mode timeout after 10 minutes for now...

In the end, I plan to make all of this stuff configurable... Basically the end game plan for this is to have a PC based GUI, that talks to the p-brain via a serial port for configuration purposes. So this way, Ill build a projector, embed a p-brain in it, then using the PC Based GUI, tweak the p-brains confguration parameters to custom fit to that particular projector's dynamics.
 
alright. lets use some common sense...a timer is just another thing to worry about...

go with a capaciter that holds power for however long...A laerger capaciter (the width of a quarter...2" tall) will have enough juice left in it after the unit's shut off that the fans could run for another....15-30 seconds.
 
alright. lets use some common sense...a timer is just another thing to worry about...

go with a capaciter that holds power for however long...A laerger capaciter (the width of a quarter...2" tall) will have enough juice left in it after the unit's shut off that the fans could run for another....15-30 seconds.

AHEM er huhuhuh!

This is about the 3rd time that the "Just Put a CAP on It" theory has been presented in this thread!

The 1st time I could understand it. Noone knew what I was doing so they chimed in etc.

The OTHER time.... I said to myself... well... this person just didnt READ THE THREAD!!!

Now YOU...

You CANNOT do what I am doing with a dang CAP! The p-brain is a projector control system... NOT... a cooling fan delay.

Wait till next version.... Im already designing it while I wait for the new lenses to come out from Lumen Labs. The next version will have:

- Bulb life counter (how long do these bulbs really last?)
- Temperature sensitivity (if it gets too hot the PJ shuts off)
- Infrared sensitivity (use a remote to interact with the projector)
- Fan speed control (If its not very hot... lower the fan speed to reduce noise)
- Character based LCD display to show current Temp, and seconds left till the timeout(s) expire.

And Im just getting warmed up.
 
OK smarty pants

maybe you can help me..
I am starting my second projector using the sony psone screen, I have already obtained a large triplet, 300W 120V lamp, and now I only need a cooling element...

Do you have any information on where to find a suggestable cooling fan that might be small and efficient for a 300W ohp lamp?
thanks for your help
 
how would I make this 12V fan run at a standard wall outlet voltage of 120V ? Is this fan even a good choice ? I really have no idea what to use here ..
 

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dale cooper said:
how would I make this 12V fan run at a standard wall outlet voltage of 120V ? Is this fan even a good choice ? I really have no idea what to use here ..

You'd need a 12V DC adapter (the sort of thing that plugs into lots of little home appliances) cut the end plug off the adapter and off the fan plug then wire them together (in your case the black and red... not the yellow). If your adapter isn't 12V then your fan just won't run at full speed.

Just be careful.
 
Ok.... so anyway....

Tonight's test was successful.

The Test was to see if after running for X time, then being shutdown, would the projector be able to be rebooted immediately.

IT COULD!

(Oh... by the way... on my testbed projector I have reduced the timeouts from hours to minutes so MAX Time On Timeout on the testbed is 6 minutes not 6 hours, and Motion Timeout is 3 minutes not 3 hours)

I booted the projector, and it was running normally...

After having the motion detector timeout nearly be reached (I went downstairs and triggered the motion detector to reset it). Then... I went back upstairs and let the Max Time On timeout expire.

So the projector immediately entered Shutting Down mode and turned off the lamp, yet let the fans run for 2 minutes (Yes... Ive changed the shutting down time to be longer).

Then, after the fans shut off (Shutting down mode ended and entered Standby Mode), I immediately tried to turn the projector back on.

The lamp didnt immediately spark but... it did come back within the timeframe I have alloted for booting the projector! I think it took about a minute and a half to TWO minutes to spark (I have previously extended the BOOT timeout to 3 minutes).

So...

The above paragraph highlights why I MUST make this thing configurable!

The reason is because.... The time it takes for my fans to cool the bulb to the point where it can be reignites is a DIRECT result of the effectiveness/ineffectiveness of the fan configuration and the fans. In otherwords, if my fans were configured differently (or if I had different fans), maybe...just maybe.... they could cool the bulb more, within the same timeframe?

So what would be really cool is to have a feature to be able to reduce/extend the cooling down time based on the projector.

When I build my next projector, it will be of a different design from this testbed. The dynamics will be completely different. Maybe Ill build a projector with a more efficient cooling system that will cool the bulb faster. MAYBE I wont! who knows. :D


So... Im happy! :)
 
time before restrike

I think the time before you can restrike an arc is not just dependant on the external lamp temperature. The space between the inner and outer glass envelopes will work as insulation, so the arc chamber will not cool much faster by adding more air flow. I bet most of the arc chamber cooling occurs by radiation rather than convection loss to the inside surface of the outer glass. Cooling the outer glass won't make that radiation loss any faster.

Should be worth a few experiments, but you should also know that MH lamps only get so many starts. Each start uses up quite a few minutes of the lamp's lifetime. Maybe for your controller testing you should use a regular light bulb instead of the MH lamp and ballast.
 
Re: time before restrike

Guy Grotke said:
I think the time before you can restrike an arc is not just dependant on the external lamp temperature. The space between the inner and outer glass envelopes will work as insulation, so the arc chamber will not cool much faster by adding more air flow. I bet most of the arc chamber cooling occurs by radiation rather than convection loss to the inside surface of the outer glass. Cooling the outer glass won't make that radiation loss any faster.

Should be worth a few experiments, but you should also know that MH lamps only get so many starts. Each start uses up quite a few minutes of the lamp's lifetime. Maybe for your controller testing you should use a regular light bulb instead of the MH lamp and ballast.

Interesting...

It definitely does seem like my lamp will restrike much sooner if the fans are left running after the lamp is shut down, but I havent actually measured it, maybe Ill do an experiment today.

I kinda figured that I wasnt doing my bulb much good by using it in during testing, especially the testing Im doing now where I might start/shutdown the projector several times in an hour.... however, I wanted to test using real a world environment for heat/light/bulb striking characteristics/etc. My current projector will end up being used just as a testbed for future controller enhancements/etc. so Im not too concerned about it.

Im willing to sacrifice one bulb for the sake of progress... :)

Question...

Currently the way the controller handles lighting the lamp, is it engergizes the ballast, and looks for light coming from the lamp. If it sees light it enters run mode, if it doesnt see light after 20 seconds it removes the energy from the ballast, waits 20 seconds and then tries to strike again.

Would it hurt the ballast/lamp if instead of cycling the power to the ballast on and off, I just powered the ballast and waited for light?
 
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