Auto on-off management - page 4 - General Discussion and Assistance - CHDK Forum

Auto on-off management

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Re: Auto on-off management
« Reply #30 on: 17 / May / 2013, 23:20:56 »
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I've been working on an intevalometer script designed to run for months at a time.   But that requires an external power source - either a really big battery and a switching power supply or a power source that draws from the electrical mains.
As promised :  http://chdk.setepontos.com/index.php?topic=9969.msg100691#msg100691
Ported :   A1200    SD940   G10    Powershot N    G16

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Offline ahull

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Re: Auto on-off management
« Reply #31 on: 18 / May / 2013, 06:26:55 »

Quote
you could also fire an input direct from a PIR module or microntroller without the need of a relay.

Except each time the PIR triggers the camera will be turned on or off.


If you use the extended delay that some PIR modules offer, the PIR could power the camera on, and the camera could take a shot  or shots or do its own motion detection to ensure the triggering object  is in the right part of the frame, and then power itself off again before the PIR delay ends. That way the PIR is always going to trigger a new shot or sequence of shots.

I have ordered a couple of those particular PIRs so I can experiment. If I get time, I am going to play with your Ultimate script too, using a different camera of course  :D
« Last Edit: 18 / May / 2013, 06:37:46 by ahull »

Re: Auto on-off management
« Reply #32 on: 18 / May / 2013, 07:21:15 »


If you use the extended delay that some PIR modules offer

Unbelievable !

How can postage from Hong Kong be just 27p ?

In a couple of decades China will rule the World.
Limited freedom-of-speech but cheap massive TV's !

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Offline ahull

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Re: Auto on-off management
« Reply #33 on: 18 / May / 2013, 09:57:39 »
Good point... furthermore... :blink: how do they manage to produce a PIR for 0.99p 

Here is the datasheet of the PIR controller chip on those boards.  Looks like a bunch of useful information if you want to extend the output period and so forth.

EDIT: I did a bit more digging about. Here is a good tutorial about these boards (the one in the tutorial looks like a slightly older version of the same basic design, using a through hole regulator and without the trimpots).

One more thought, if you decide to run one of these from batteries, you could cut down the power it uses even further, by linking out the on board regulator and running the whole thing from 3v3 from the buck regulator you are probably going to power the camera from.
« Last Edit: 18 / May / 2013, 13:41:43 by ahull »


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Offline ahull

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Re: Auto on-off management
« Reply #34 on: 22 / May / 2013, 12:45:55 »
I had a few spare moments at lunch time today. Not enough time to actually operate on the camera unfortunately, but time enough to try my hand at soldering on the scale of an Ixus mother board.

The results were encouraging, I has a couple of scrap boards (a donated, dead photo printer and an A3100 that someone gave me after it had had one trip to the seaside too many).



It seems that I am not quite as rusty when it comes to soldering as I feared. I quite easily managed to solder some fine enamelled wire to pin 4 on both the printer board (very easy, even without additional flux) and also to the canon board (a bit more tricky, space is much tighter, I think I may need to get a smaller tip for my iron). I also recovered a couple of switches from the printer front panel board and popped them on some perfboard to use as my power on/off/shoot controller.

I then set about trying to recover some small diodes from the Canon board.

Actually if I am being honest, I have plenty of diodes already, I was simply overcome with the urge to apply my small gas torch to the Canon board, to see what damage I could do, and if in the process I liberated a couple of usable SMD diodes, some smoke, toxic fumes and slightly singed my fingertips that would all add to the fun. Not sure what I will do with the bits I recovered, maybe I'll make  some very geeky cuflinks.



More results from the dissection here.
« Last Edit: 22 / May / 2013, 13:12:44 by ahull »

Re: Auto on-off management
« Reply #35 on: 22 / May / 2013, 17:54:12 »
If you can remove components without the aid of a stereo microscope or bench magnifier then they are relatively massive !  :)

How did you remove the ball grid array devices ?

You need an Antex 0.12mm tip diameter soldering tip.

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Offline ahull

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Re: Auto on-off management
« Reply #36 on: 22 / May / 2013, 20:01:22 »
If you can remove components without the aid of a stereo microscope or bench magnifier then they are relatively massive !  :)

How did you remove the ball grid array devices ?

You need an Antex 0.12mm tip diameter soldering tip.

Removing components is the easy bit, as I said its all hot air, in this case a small blowtorch, scanned quickly back and forth over the board. The skill is to judge the time so you don't actually just fry everything. Once the board is good and hot a quick tap and everything drops of the board, BGA devices included.





Picking and placing the recovered components is where the real skill comes in. That does require some magnification and a steady hand. It is actually possible to do BGA repairs with a blowtorch, (youtube has a few demos), but a hot air gun or better still a proper hot plate is a lot easier. As to trying to fix a Canon double sided board with a blowtorch, not even the best solder ninja in the known universe would manage. The board is way too small.

Adding a diode to the Ixus is small beer by comparison. As you say a 0.12mm tip (and a steady hand and some x4.5 reading glases) should be enough.  I'll keep you posted with more pics if and when I get a chance to try.
« Last Edit: 22 / May / 2013, 20:06:16 by ahull »

Re: Auto on-off management
« Reply #37 on: 23 / May / 2013, 05:20:01 »
I do have a proper hot-air gun, have never used it, maybe I should.

I wonder how many of the removed components are functional, not that it matters ?



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Offline ahull

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Re: Auto on-off management
« Reply #38 on: 23 / May / 2013, 18:18:48 »
I do have a proper hot-air gun, have never used it, maybe I should.

I wonder how many of the removed components are functional, not that it matters ?

Well in this case, I would doubt that all of them are fully functional, as I said, the camera had been "to the seaside". The board was fairly heavily corroded by seawater, (enough to dissolve the battery terminals). Probably most of the  components would be OK, but anything with corroded terminals would be a write off. Interestingly the Digic III and the ram chip both looked unscathed.  If any soldering ninja fancies making a Digic III breakout board, give me a shout.

Failing that I wonder what going rate on ebay for Digic related cuff links is like. I suspect it is just about as poor as the market for lapsers fog pictures. 

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Offline ahull

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Re: Auto on-off management
« Reply #39 on: 28 / May / 2013, 12:30:35 »
It occurs to me that the poster of this topic may have missed this previous post on the same subject...

This obviously only applies if you are trying to control the camera and it is running from an external power source.

Most (all?) Canon models will power up (and also load CHDK  and any script you want, if you set it to start at power up) if you hold down the power button (i.e. tape it down or keep it pressed by some mechanical means), prior to switching on the external power source.

In other words, the answer may be to power the camera from an external source, which you control (with a relay or transistor/mosfet or other switch).

This certainly works with the following Ixus 30,40,50,60,70 and 850 IS.

I would imagine it works with most others. All of these models will power on, and stay on, despite the fact that the power switch is held down. 

If however you need to control the camera directly and run it from its own batteries, I fear "surgery" is the only way.

Once the camera is on, it would be the responsibility of your script to take the picture, and if necessary stow the lens afterwards, before the external power is switched off again. A clever feedback method for switching off the external source might be to use one of the camera LEDs as half of an optoisolator. A blink of the LED could then instruct the power controller to switch the camera back off once its work was done.
« Last Edit: 28 / May / 2013, 12:33:51 by ahull »

 

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