Canon Ixus 870IS/ SD880IS (and other newer Canons?) output issues

edited June 2009 in KAP Cameras
As succesor of my wonderful Canon A570IS KAP camera (that began to have errors writing jpeg sometimes) I was looking for a wide angle camera preferably with CHDK, and came to the Canon Ixus 870IS (SD880IS):
* 28mm wide angle
* 32 MP/cm² pixel density
* good reviews for photo quality on Dpreview and Cnet
* 205 grams with battery
* it has a working CHDK (at the moment only some functions not needed for KAP are missing)

While the spec's and reviews are positive.
Is it in practice the perfect camera for KAP?
Well: not exactly.

After getting the camera I found some issues with this camera:
1) LCD display eats batteries, however you cannot switch it off on the 870IS: Pressing 'display' button will only toggle between the display between modes with more or less information on the display, but the LCD will stay on. In the manual, you can find that you can assign the print-button for switching the display of. By holding the print button in record mode, the LCD will switch off, but the LCD will switch on automaticly the moment a picture is taken. It is said this is because there is no viewfinder on the camera.

2) For a Video downlink: the camera has no separate connector for video out. There is a propriety video cable delivered by the camera, and when inserted the video output is redirected from the LCD display to the cable.
But the cable connects to the USB port on the camera... the port you like to use for triggering the camera!
The propriety video cable has 6 pins on the narrow side of the mini-usb connector:

while a standard USB has 5 pins on the opposite side (the wider side):

So no way to modify a USB-cable to get video, or even combining it with USB-triggering. Damn.

I really considered bringing the camera back.

However there is rescue:
1) Virtually pushing the print-button with CHDK proved hardly doable in timing and hardly effective if you make a fast sequence of pictures.
However since around january 2009 the following command is available in CHDK: set_backlight 0

As a simple example:

:loop
set_backlight 0
do
a = get_usb_power
set_backlight 0
until a>0
shoot
goto "loop"

The display still will switch on when making a picture, but within a fraction of a second be switched of again (in the next loop waiting for usb), so minimal loss of power.

2) Either a usb-connector for USB-triggering or for video downlink but not combined isn't very nice, so what really idealistic would be needed is a tiny mini usb-connector with: 11 pins...
Well: 11 pin connectors that are almost like mini-usb connectors are available: for the HTC Touch mobile (or G1 android mobile phones), called 'ExtUSB". They ExtUSB is bigger (for example one square corner), and won't fit in a standard sized usb port. Converters are available, e.g. this one.

The wiring of pins proved to be probably not usable for the Canon, so rewiring or microscopic chirurgical modifications could be needed.
I was happily astonished when I found this little gem: a 11-pin mini usb connector with breakout.
I ordered it via Coolcomponents.
The connector is too large for the Canon usb-port, but it comes in 3 separate pieces, it is easy to handle with. I removed the metal chassis, and cut some edges of the plastic, and the connector fitted.

The layout of the breakout:
6 9 11 5
O O O O
7 8 10 4
O O O O
1 2 3
O O O

Pins 1 to 5 are the standard USB pins:
1: USB VCC +5v
2: USB Data -
3: USB Data +
4: N / C
5: USB GND

After some research on the proprietary cable, and trial on the breakout connector I found out that Canon uses:
6: Ground
7: Short with pin 6 for enabling video output
8:
9: Audio
10: Video
11:
12: Chassis Ground (GND)

It works! The camera can be triggered with CamRemote via pin 1 and 5, and was able to get video output with 6&7 as ground and [edit]10 (thanx to David Sykes for reading carefully)[/edit] as video.
Test setup for video output: .
Using this connector is another solution for the LCD off issue.

So, with some effort, the Canon can be a good KAP camera after all. Above story will hold for the Ixus860IS/SD870IS also.

And for a last issue:
3) 28mm wide angle made a rig leg visible in the image! Duhhh... ;-)

Comments

  • Hi Fabian,

    Time well spent to find out a way to make this a useable KAP camera with both CHDK and video capability at the same time.

    Concerning the last issue - don't use the legs. I haven't used them since 2007. Got a little bit more cautious, though (which doesn't do any harm)... :0)
  • Well, I do like legs on the rig: for safety with a hard landing, for keeping the camera getting dirty with a soft landing, and practical: you can confortably put the rig on the ground (or at home on a table) while doing other things.
    With some physical rearrangements, the one leg isn't in the image anymore, so issue solved. I could also easily cut the legs with scissors to make them a bit shorter because (they are made from plastic)
  • Hmmmm, what I could find on the internet is that issue #2 (propriety 6pin av out port combined with standard usb port) also applies to several other newer Canon models e.g. ixus95is/ sd1200is, sx200, ixus980is/ sd990is, A2000is, and A1000is.
    So beware of that (or any other experience with that?)
  • edited November 2009
    That's a good find locating that connector. The common name for it is "HTC ExtUSB" due to its use in HTC phones.

    Sparkfun has both the breakout connector mentioned above as well as the bare connector without the circuit board on the end. It turns out that if you pull the plastic part out of the connector and file down the shoulders of the connector, you can push it into a standard USB Mini-B connector shell.

    Combined Video/CHDK Cable

    Here's a picture showing the pinouts for those not using the breakout board. This is looking into the plug on the end of the cable. I found that Chassis Ground and USB Ground are the same and Pin 8 is tied to Pin 7 on a SD940.

    11 pin Canon Pinout

    Another interesting thing is that Canon is putting this connector on the back of some of their smaller cameras rather than on the side. This might be a more KAP-friendly way for cables to exit the camera.

    Combined Video / CHDK
  • edited August 2010
    Hi Fabfoto,

    Thanks for this great info. I am planning to buy this connector from sparkfun.com but was wondering - how did you pull the metal case of this connector? - I mean without destroying the plastic inside - it's kind of difficult in the images.


    Joe
  • edited August 2010
    Hi Joe,

    I've got the breakout version. If I remember well, it was was not all too hard to remove the metal case. If you look at a regular mini-usb connector you can see there is a small breaking path at the narrow side of the plug. With some pincer/ tweezers and bending, you can unfold the metal case there.
    Triggering CHDK can be done with putting a +5V pulse on pin 1.

    Fabian.
  • But I can use the original cable? 1 for USB shutter and 1 for video?
  • (I'm not sure whether I understand the question right) Original video cable delivered with the Canon can also still be used, but then without chdk/ usb function. Or a usb cable can be used, but then without video.
  • Ok the HTC plug are arrive!

    1) I've removed the metal part but at the end I've to replace with the original chassis of my CANON mini USB?
    2) The ground are PIN 6 e 7 but I've to connect to Chassis Ground?
    3) For shutter circuit (I've duneCAM) I've to made a circuit with 5V battery or can I use other way?

    Thanks again
  • 1) It is not absolutely necessary. It worked for me without a chassis, as long as the connector will keep tight enough in the camera. Scott Armitage succeeded in wrapping a chassis on the connector.
    2) The same: also not absolutely necessary, worked for me without.
    3) My expectation is that the duneCAM should nicely work because it has a chdk signal output pin, and you can connect it to pin1 of the usb connector.
  • edited October 2011
    Good news for people who are frustrated by the fact that many Canons have a combo plug (as noted above) and do not have time or skill to work with the separate components shared above ...

    At LONG LAST, today a solder-ready video-OUT signal-IN plug is available. This should work with Canon ixus95is/ sd1200is, sx200, ixus980is/ sd990is, A2000is, and A1000is.

    It is here from Peter at KAPShop.

    Phil
  • It has been available here as well, no soldering needed and compatible with CAMremote.
  • Hello, I understand this is an older thread, but maybe someone can help me. I am trying to use a Canon camera(sx110is) for arial photography. I would like to have Video output, with a USB trigger. I currently have an older interface(RC interface) manufactured by BLIP that will actuate the camera via USB and it works great.
    I purchased the HTC connector with pinouts from Sparkfun and removed the metal shielding and soldered the wires.The connector seemed to fit very well and the video out works fine, but the USB functions do not. It seems as though the connections may not be making proper contact inside the connector.
    Does anyone know if some of the USB connections do not make proper contact with this connector?( + and- data) I guess as long as the +5 and ground make contact internally, I could use CDHK and trigger it that way. I have not checked this yet.
    I see that there are some pre-made cables on the market with usb and video(and pin 7 may not be grounded?), but they are very expensive and I already spend the $15 for the HTC connector.

    Any thoughts?
  • edited October 2013
    VBUS and GND signals in USB connector are needed for CHDK/SDM.
  • I could not get the USB/VBUS/GND functions to work for me. After a ton of testing, It seemed like the contacts inside the plug were not making a proper connection. Out of frustration, I hacked the plug apart and found 4 of the pins on the USB side were very short. I'm not sure if this plug was defective, but I sent a picture to Sparkfun to see what they think.
    image
  • Sparkfun contacted me about the plug today and checked the contacts with another HTC breakout connector in stock. The said the pins were the same(ground long, other 4 shorter) I'm not sure why I can not get contact with the +5 and Ground on my Canon SX110is or Sd790is with this connector?
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