First of all, I’m not really a expert on electronics, so bear with me :wink: I bought a Spark Core Maker kit (will all kind of stuff in it) and I started with the “Measuring the temperature”-sample on http://docs.spark.io/#/examples I have connected everything the same way as on the photo and flashed my core with the example program. When I retrieve the values from the input pin I get values around 1300. When I convert this to a voltage I get 1.04v. Convert this into a temperature I get 55 degrees Celsius. I’m very sure, it’s not that hot in here :wink: So, what’s going on? Can somebody tell me what I’m doing wrong? I followed the example to the letter.

@BDub, I thought based on the TMP36 datasheet there is no external calibration required, and my measured deviation was beyond the accuracy listed in the datasheet. Am I understanding something wrong there? @defsdoor, the voltage factor should be 3.3 instead of 3.0.

@Heri yeah, you’re right… I was hoping to sneak one past you… haha. Really though… is it a consistent offset? Can you show a picture of your wiring? When I get the TMP36 that I ordered…like 2 weeks ago! I’ll have my hands on this problem and offer some better solutions.

[image] Peerke: 0.01 μF ceramic cap Can someone please put up a photo of what putting the ceramic cap from GND to AO looks like? Got my training wheels on and some of this is hard to visualise. So a photo or fritzing diagram of the final config would be great! Thanks in advance.

[image] This is the config I have. 0.01uF cap on pin 1, 3 of the TMP 36. Getting all sorts of queer readings so wondering if I have a faulty TMP 36 as it jumps by 1000 units per 5 secs etc etc.

Whoops obviously when I have A0 connected properly. It still jumps around even though I’m stupid.

@Pharmboyz try these changes :wink: [image]

@BDub, thanks for your support. My wiring is: image (as a new user I can’t include it here)

Hi Guys, Very new to the electronics side of the picture. I picked up on of these for an outdoor project I’m slowly working on. I’m getting some odd readings out of it. The analog reading seem to wildly vary between 2000 and 3000 so I get results like ( ( ( (2000 * 3.3) / 4095 ) - 0.5) * 100 ) = 111 degrees. Definitely doesn’t sound right for cold wet Britain. I have: a jumper from 3.3* to the power, a jumper from data line to A0 a jumper from GND to GND probably missing a cap or resistor somewhere. Anybody able to tell me what I’m doing wrong? Cheers, Stuart

See above - you are missing a capacitor.

Don’t think it’s just that. Having had a read in a few places, it looks like this uses OneWire. I used @tidwelltimj’s implementation of that from here Arduino bildr acticle on using this component Data sheet I think I’ll stick in a 4.7k resistor and test using the OneWire lib again. Unless someone thinks otherwise?

"Measuring the temperature"-sample not getting to work correctly

Troubleshooting

BDub January 16, 2014, 7:18pm 22

@Pharmboyz try these changes

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"Measuring the temperature"-sample not getting to work correctly

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