Battery third (temp) terminal as multipurpose analogue input

c_joerg

1247

Re: Battery third (temp) terminal as multipurpose analogue input

« Reply #190 on: 06 / August / 2018, 05:22:13 »

Advertisements

If you would provide a dummy battery with a shunt, could you measure the current consumption of the camera with the AD converter?

Logged

M100 100a, M3 121a, G9x II (1.00c), 2*G1x (101a,100e), S110 (103a), SX50 (100c), SX230 (101a), S45,
Flickr https://www.flickr.com/photos/136329431@N06/albums
YouTube https://www.youtube.com/channel/UCrTH0tHy9OYTVDzWIvXEMlw/videos?shelf_id=0&view=0&sort=dd

ottokar

29

Re: Battery third (temp) terminal as multipurpose analogue input

« Reply #191 on: 02 / January / 2019, 06:48:13 »

Hi,
I have a question about using the temperature terminal as a remote trigger. The option should appear under the Remote Parameters section of the menu, right? I have an Ixus 75, chdk 1.4.1 from August 2018, and there is no option mentioning anything about using the battery terminal as a remote trigger.
Is it only applicable to newer cameras?
thanks,
Andrew

Logged

reyalp

14037

Re: Battery third (temp) terminal as multipurpose analogue input

« Reply #192 on: 02 / January / 2019, 16:06:00 »

Quote from: ottokar on 02 / January / 2019, 06:48:13

Hi,
I have a question about using the temperature terminal as a remote trigger. The option should appear under the Remote Parameters section of the menu, right? I have an Ixus 75, chdk 1.4.1 from August 2018, and there is no option mentioning anything about using the battery terminal as a remote trigger.
Is it only applicable to newer cameras?
thanks,

It needs to be enabled per port, which we generally only do after someone has tested it. If you post which Canon firmware your camera has, I can post a test build.

Logged

Don't forget what the H stands for.

ottokar

29

Re: Battery third (temp) terminal as multipurpose analogue input

« Reply #193 on: 02 / January / 2019, 18:46:02 »

Hi reyalp,
the firmware version is ixus75_sd750-102a, please don't rush to build it as I need (lots of) time to make a 3 terminal battery (with each terminal positioned precisely enough),
many thanks for helping,
andrew

Logged

reyalp

14037

Re: Battery third (temp) terminal as multipurpose analogue input

« Reply #194 on: 03 / January / 2019, 02:36:42 »

Quote from: ottokar on 02 / January / 2019, 18:46:02

the firmware version is ixus75_sd750-102a, please don't rush to build

It's an easy change. Test build attached.

Quote

it as I need (lots of) time to make a 3 terminal battery (with each terminal positioned precisely enough),

FWIW, I found it pretty easy to bodge a usable terminal on all my lithium battery cameras using either a real battery or the canon fake battery adapter. See https://chdk.setepontos.com/index.php?topic=10385.msg137582#msg137582 for an example.

ixus75_sd750-102a-1.5.0-5145-reyalp-batt-remote-test-1.zip (866.84 kB - downloaded 40 times.)

Logged

Don't forget what the H stands for.

ottokar

29

Re: Battery third (temp) terminal as multipurpose analogue input

« Reply #195 on: 03 / January / 2019, 13:20:35 »

Hi reyalp,
so I loaded this, with a real battery and copper foil tape + wire + a 1k resistor acting as a controllable middle terminal, and I attached a usb cable purely so I could touch the resistor to the cable ground for my on/off pulse.
When I grounded the end of the resistor, the AF assist light goes on and shooting starts (and sometimes completes) but then the lens retracts, the camera says 'change the battery' and it shuts down. If it actually shoots a photo, then it completes saving the photo to the sd card first.
the battery reports 80+ % in chdk. No scripts were running. I saved the crashlog but when I opened it, the date is from October 2018 (and the camera date is correct, it knows today is 3rd Jan 2019), so it doesn't seem to be related.
there's no urgency at all for this,
thanks,
andrew

Logged

reyalp

14037

Re: Battery third (temp) terminal as multipurpose analogue input

« Reply #196 on: 06 / January / 2019, 19:52:58 »

Quote from: ottokar on 03 / January / 2019, 13:20:35

Hi reyalp,
so I loaded this, with a real battery and copper foil tape + wire + a 1k resistor acting as a controllable middle terminal, and I attached a usb cable purely so I could touch the resistor to the cable ground for my on/off pulse.

Did you try shooting manually using the shutter button with the same rig in place?

You could also switch CHDK battery display to voltage so you can watch what it does when you connect the remote. If you do this with remote disabled, you can check if it's the electrical connection alone is enough to trigger shutdown, or if it's tied to the shooting process.

1k is pretty low, from my notes the camera would see this as about 80c, which could conceivably trigger some protection software. Something like 3k should trigger reliably without sending extreme values to the camera.

Logged

Don't forget what the H stands for.

Ant

509

Re: Battery third (temp) terminal as multipurpose analogue input

« Reply #197 on: 07 / January / 2019, 13:58:36 »

Just FYI.
Playing with QEMU I discovered that Canon EOS M3 measures the voltage at the USB power input using ADC channel #2 to detect USB connection. (see 0xFC074F72)
Maybe other cameras can do that too.

« Last Edit: 07 / January / 2019, 14:19:07 by Ant »

Logged

ottokar

29

Re: Battery third (temp) terminal as multipurpose analogue input

« Reply #198 on: 07 / January / 2019, 14:30:09 »

Hi reyalp,
it all works now, thank you. first, testing whether the battery had enough power left to shoot at all showed that it did. The I disabled remote, and just grounding the 1k resistor made the camera shut down with the 'change battery' message.

Using a 5k resistor instead worked fine, completely as expected,
andrew

Logged

reyalp

14037

Re: Battery third (temp) terminal as multipurpose analogue input

« Reply #199 on: 08 / January / 2019, 00:23:06 »

Quote from: ottokar on 07 / January / 2019, 14:30:09

Using a 5k resistor instead worked fine, completely as expected,

Thanks for confirming. I've enabled this in the trunk 1.5 autobuilds starting at 5149

Logged

Don't forget what the H stands for.