Interfacing BMP085, DHT22 and TSL2561

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d7x
 
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Interfacing BMP085, DHT22 and TSL2561

Post by d7x »

I'm trying to use all 3 sensors using the directions for all 3 in the Learn tutorial for each sensor. I can see valid readings from the BMP085 and the DHT22 when they're connected together. When I add in the TSL2561, I'm getting 0 Lux readings. However, when I only run the TSL2561, I get valid Lux readings. I'm guessing that this is an i2c issue since the BMP085 and the TSL2561 both use i2c. I've followed the suggestion to wire the TSL 2561's ADDR to either VCC or GND and the changing the declaration to either Adafruit_TSL2561_Unified tsl = Adafruit_TSL2561_Unified(TSL2561_ADDR_HIGH, 12345); or Adafruit_TSL2561_Unified tsl = Adafruit_TSL2561_Unified(TSL2561_ADDR_LOW, 12345); However, I'm still seeing 0 Lux readings for the TSL2561.

What is the easiest way to debug an issue like this quickly? Would any test tools like a logic analyzer or oscilloscope make solving issues like this a lot easier? Or even a multimeter?

Finally, any ideas on what I should do to solve this issue? Thanks.

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adafruit_support_bill
 
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Re: Interfacing BMP085, DHT22 and TSL2561

Post by adafruit_support_bill »

You shouldn't have an address conflict between these two devices. Even if that were the case, I'd expect BMP085 readings to get corrupted as well. Since both breakouts have pullup resistors, one possibility is that the combined pullups are too strong for the TSL2561. If that were the case, a scope would be able to show you.

The Bus Pirate is another cost-effective tool for analyzing i2c communication: https://www.adafruit.com/product/237

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