Author Topic: Oled display changed  (Read 559 times)

Kimwo

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Oled display changed
« on: December 30, 2018, 04:55:04 PM »
Taking guidance from the Andreas Speiss video I commented out nanoAmp from the autoranging and uploaded the modified sketch.  This works well but now instead of showing a micro symbol it show "1/2" on the microAmp range!!    Any ideas?  A small thing but it would be nice to get original display back.

Felix

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Re: Oled display changed
« Reply #1 on: December 31, 2018, 10:00:51 AM »
What display are you using?
Are you using the right u8g2 library?
Any changes to the original firmware other than the commented lines of code?

Kimwo

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Re: Oled display changed
« Reply #2 on: December 31, 2018, 05:21:26 PM »
1) one of your white oleds 128x64 purchased at the same time as the currentranger
2) the library from the reference in the software - but it may be wrong I suppose
3) commented out the line, thus disabling nA range in auto mode as per Andreas Speiss video.

It is not a huge problem, just curious.

Kimwo

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Re: Oled display changed [SOLVED]
« Reply #3 on: January 01, 2019, 03:51:19 PM »
An update:
1) I reloaded the original software from github and found the problem went away
2) I found if I made ONE character change to the the sketch - changing the LDO voltage from 3.300 to 3.307 as per my printed data, then the micro character changed - this time it became a question mark!
3) Even more curious - I found that the error occurred if I made the change to the Arduino IDE but NOT if I amended the orginal .ino with a text
editor and then loaded it.  Very wierd - no idea why.

Either way it is not a problem with the software.  Andreas Speiss's mod does work (sort of - I shall put a comment on his video).

Great piece of kit - now I have to learn how to up the logging rate.  Thanks.
« Last Edit: January 04, 2019, 08:31:30 AM by Kimwo »

alexsh1

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Re: Oled display changed
« Reply #4 on: February 03, 2019, 04:22:34 AM »
What's the point of disabling nA? You are buying an ammeter and disabling some functions deliberately?

Felix

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Re: Oled display changed
« Reply #5 on: February 04, 2019, 11:02:31 AM »
What's the point of disabling nA? You are buying an ammeter and disabling some functions deliberately?
Since the firmware is available, anyone can change the behavior in whatever way they want to suit their needs.

I think after a video by Andreas who did the same for this review, some folks decided they do not need the nA range and did the same.
Some early units shipped with a firmware that did much less averaging and that might have caused it to be very sensitive in the nA range. It depends on a lot of things not just terminals or software averaging.

Kimwo

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Re: Oled display changed
« Reply #6 on: February 06, 2019, 01:23:16 PM »
What's the point of disabling nA? You are buying an ammeter and disabling some functions deliberately?

As Andreas said "The nano ampere range is quite delicate and I did not want that the automode accidentally selects this range ..."
I agreed with him.  I have blown up the lower ranges of multimeters in the past.  The nanoAmp range can still be selected manually.  I could probably still blow it up ;)

alexsh1

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Re: Oled display changed
« Reply #7 on: February 07, 2019, 04:06:26 AM »
Since the firmware is available, anyone can change the behavior in whatever way they want to suit their needs.

I think after a video by Andreas who did the same for this review, some folks decided they do not need the nA range and did the same.
Some early units shipped with a firmware that did much less averaging and that might have caused it to be very sensitive in the nA range. It depends on a lot of things not just terminals or software averaging.

Fair point! Question to you, Felix - do you think it is possible to damage nA in automode in the nA range?
Surely, there are many ifs and buts, but as far as I can tell from the software, as soon as there an overload, the range goes up to uA or mA.

alexsh1

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Re: Oled display changed
« Reply #8 on: February 07, 2019, 04:11:12 AM »
As Andreas said "The nano ampere range is quite delicate and I did not want that the automode accidentally selects this range ..."
I agreed with him.  I have blown up the lower ranges of multimeters in the past.  The nanoAmp range can still be selected manually.  I could probably still blow it up ;)

I suppose everyones' needs are different. Part of the reason why I purchased the CR was that it is more sensitive in nA than uCurrent.
uCurrent is good, but in nA it is simply too noisy. I think I have a few sensors with a sleeping current being 250nA or around and I am using this range.
BTW, I have sold uCurrent recently as it is no use for me now. I use exclusively the CR with OLED or DMM (which has got uCurrent built-in).

Felix

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Re: Oled display changed
« Reply #9 on: February 07, 2019, 12:45:34 PM »
The nanoAmp range can still be selected manually.  I could probably still blow it up ;)

Fair point! Question to you, Felix - do you think it is possible to damage nA in automode in the nA range?
Surely, there are many ifs and buts, but as far as I can tell from the software, as soon as there an overload, the range goes up to uA or mA.

Guys, the nano amp range goes through a 10K shunt. Not sure what you mean by blowing na Range up, but that impedance is very high so any serious load will brown-out in that very quickly (if the auto-ranging of a few milliseconds is still too slow). If you add the diode across the posts (from input+ to input-) that will limit the drop to the diode drop, the CR sees the diode drop which will saturate the opamps but still won't really do damage because "OVERLOAD" is going to rail and that's within expected extremes.

And no, I have not seen that happen or blown any ranges myself in all the development and testing that I've done on my own.

alexsh1

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Re: Oled display changed
« Reply #10 on: February 08, 2019, 03:56:58 PM »
Guys, the nano amp range goes through a 10K shunt. Not sure what you mean by blowing na Range up, but that impedance is very high so any serious load will brown-out in that very quickly (if the auto-ranging of a few milliseconds is still too slow). If you add the diode across the posts (from input+ to input-) that will limit the drop to the diode drop, the CR sees the diode drop which will saturate the opamps but still won't really do damage because "OVERLOAD" is going to rail and that's within expected extremes.

And no, I have not seen that happen or blown any ranges myself in all the development and testing that I've done on my own.

Thatís what I see imperically as well.
And I have used the CR VERY extensively!

Felix

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Re: Oled display changed
« Reply #11 on: February 08, 2019, 06:01:27 PM »
And I have used the CR VERY extensively!
Awesome, and is it holding well?
To your expectations?
Happy with your CR so far?

alexsh1

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Re: Oled display changed
« Reply #12 on: February 09, 2019, 04:45:33 PM »
Awesome, and is it holding well?
To your expectations?
Happy with your CR so far?

Absolutely happy! I have been looking for a small device to test nodes and sensors (sleeping / waking up). I had a few boards with unusual battery consumption which turned out to be flash not sleeping / bad sensor / bad soldering / wrong components etc. I needed the CR to be precise, small AND with the display - all features the CR has. In my view, uCurrent is good, but too fiddly with all the wires to go / from it. I have now the 121GW and it has uCurrent built-in so uCurrent has been recently sold. I just hook up the CR between a battery and a battery contact using quality Test Hook Clip Cables like this https://www.amazon.co.uk/dp/B07GB6DBH5/ref=asc_df_B07GB6DBH558417810/?tag=googshopuk-21&creative=22146&creativeASIN=B07GB6DBH5&linkCode=df0&hvadid=256110712503&hvpos=1o4&hvnetw=g&hvrand=16153927143245287787&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9045894&hvtargid=pla-535458447081

When the sensor is in a location difficult to reach, the CR is just sooooo handy. On a number of occasions I nearly dropped my DMM from a considerable height. Right now, after extensive testing, the CR is only tool I am using for nA/uA/low mA testing. And autoranging is just a must for testing sleeping nodes consumption.

Felix

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Re: Oled display changed
« Reply #13 on: February 09, 2019, 06:39:54 PM »
Thank you, I appreciate the feedback!
Do you feel the LiPo and built-in charger is a hassle, or a convenience?
Would you see a non-chargeable battery option like CR123 (or even a 3xAAA pack) a good alternative?

alexsh1

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Re: Oled display changed
« Reply #14 on: February 10, 2019, 04:43:16 PM »
Thank you, I appreciate the feedback!
Do you feel the LiPo and built-in charger is a hassle, or a convenience?
Would you see a non-chargeable battery option like CR123 (or even a 3xAAA pack) a good alternative?

I think it depends on usage. Personally I think LiPO is just brilliant. One a particular day, I managed to completely discharge it. I think I have 1500mAh battery. CR123 maybe good for occasional usage or usage with DMM only without a display (not for me). In my view CR123 is a very limited option. The same as CR2032 for uCurrent. Dave recommends this for uCurrent:

Quote
For increased battery life and greater potential output voltage swing, 3 x AAA batteries in series can be used instead of the coin cell. No modifications are required, just wire in parallel with the existing coin cell holder. A 3 x AAA holder fits in the existing box.


And I use USB for everything - programming Arduino or ESP8266 or just 5v power so charging from USB is an excellent option