ISL29125 issues

Hi everyone.
I’m a newbie to the world of circuits.

I’m trying to get readings from an ISL29125, I am using a Arduino Mega to run the device off.

I am using the code that thinkspeak provides. I keep getting readings of FFF for RGB values on the serial monitor.

I tried hooking up the sensor to A4 and A5 pins without success. I’ve also tried connecting it to the Arduino SCL and SDA pins, with no success.

ANY HELP IS WELCOMED.

ISL29125Basics.ino (1.67 KB)

You failed to post a wiring diagram so I assume the error is there.

As the chip cannot be used directly (surface mounted) on a breadboard I guess you're using a breakout board. You failed also to post the schematics of that board.

I tried hooking up the sensor to A4 and A5 pins without success. I've also tried connecting it to the Arduino SCL and SDA pins, with no success.

SDA/SCL are not on A4/A5 on the Mega2560! You must not connect the sensor directly to the Mega2560's SDA or SCL pins as these have a 5V level (on-board pull-ups) which may damage the sensor immediately.

I would start by downloading a I2C scanner program and see what address appears for the ISL29235 device' The I2C does not follow the accepted standard of allowing pull up to +5. Most devices accomplish this using open Drain outputs with outputs that can tolerate the +5. Be sure you have pull up resistors. If it is a SparkFun board there are solder jumper pads that will connect the pull ups shown in there schematic. Simply add solder to the pads. If this does not work try with some other I2C 5V tolerant board with the scanner to validate the I2C connections.

Thanks for the tips. Going off what Shannon said I think I might have fried the board.

I had looked up tutorials and I thought I wouldn't need a logic converter or breakout board.

I ran code to scan for I2c and the Arduino isn't getting any readings from the ISL29125, which make me think again that its fried.

Here's a picture of the way I have it wired up.

Here's a picture of the way I have it wired up.

On that picture we see a (red) breakout board. Post a link to the schematics of that board as it seems to have additional circuitry (other than the sensor itself) on it.

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