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Feather HUZZAH32 I2C pullup resistor placement (pic)
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Feather HUZZAH32 I2C pullup resistor placement (pic)

by icodegfx on Wed Sep 22, 2021 7:53 pm

Hi guys, the HUZZAH32 overview states that the I2C data pins need a pullup resistor.

Note that the I2C pins do not have pullup resistors already! You must add them if you want to communicate with an I2C device


I'm planning on using an RGB color sensor and was hoping I could get a second set of eyes on this diagram. What I am not fully certain about is the placement of a 10k (10k?) resistor.

New Project.jpg
New Project.jpg (89.59 KiB) Viewed 39 times


Thanks.

icodegfx
 
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Re: Feather HUZZAH32 I2C pullup resistor placement (pic)

by icodegfx on Thu Sep 23, 2021 8:15 pm

I'm not really sure where to go from here.
- I checked my soldering and it looks solid.

huzzah32 tcs34725 RGB sensor (1).jpg
huzzah32 tcs34725 RGB sensor (1).jpg (314.11 KiB) Viewed 27 times


- I shifted the boards on the breadboard to make sure it is not a faulty one
- I disconnected and reconnected all the cables to make sure they were making contact
- I tried using both M0 and M1 data pins on the HUZZAH32
- I tested the HUZZAH32 and it runs other sketches just fine
- I even tried resistor values ranging from 1.5k to 10k

New Project (1).jpg
New Project (1).jpg (99.51 KiB) Viewed 27 times


any suggestions would be most welcome

icodegfx
 
Posts: 17
Joined: Thu Jan 16, 2020 9:54 pm

Re: Feather HUZZAH32 I2C pullup resistor placement (pic)

by icodegfx on Thu Sep 23, 2021 11:11 pm

ok I found this suggestion on another post.

Try I2CScanner.jpg
Try I2CScanner.jpg (34.25 KiB) Viewed 24 times


I tried the I2CScanner.ino sketch and I get this output:

I2CScanner output.jpg
I2CScanner output.jpg (33.18 KiB) Viewed 24 times


Adafruit please advise:)

icodegfx
 
Posts: 17
Joined: Thu Jan 16, 2020 9:54 pm

Re: Feather HUZZAH32 I2C pullup resistor placement (pic)

by adafruit_support_carter on Fri Sep 24, 2021 12:54 pm

Adafruit I2C breakouts include the required pull up resistors. So you don't need to add any additional external resistors.

Here's how to wire the sensor to a Feather:
https://learn.adafruit.com/adafruit-col ... -2976705-1

Looks like you're on the Feather's SPI pins, not the I2C pins. So just need to remove the external resistors and re-wire to SCL/SDA.

adafruit_support_carter
 
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Re: Feather HUZZAH32 I2C pullup resistor placement (pic)

by icodegfx on Fri Sep 24, 2021 3:00 pm

Looks like you're on the Feather's SPI pins, not the I2C pins. So just need to remove the external resistors and re-wire to SCL/SDA.


Egg on my face. Thank you Adafruit. It works beautifully.

Found RGB Sensor.jpg
Found RGB Sensor.jpg (83.08 KiB) Viewed 15 times

icodegfx
 
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Re: Feather HUZZAH32 I2C pullup resistor placement (pic)

by adafruit_support_carter on Fri Sep 24, 2021 5:07 pm

Yeah! No worries. Glad it was something easy and it's working now. Have fun!

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Please be positive and constructive with your questions and comments.