[FAQ] OPT3001: Is there example raspberry pi code for the OPT3001?

I attached the daughter card of an OPT3001 EVM to the I2C bus of the raspberry pi and wrote some experimental code to operate it, with success!  Here are my notes and the code I used as I did this:

Code: opt3001_c.txt

Example Output File: opt3001_c_output.txt

Some of my notes:

Used raspibian image on SD Card

Expanded filesystem

$Raspi-config and turned on spi and i2c

Edit the modules file

sudo nano /etc/modules

Add these lines:

i2c-bcm2708

i2c-dev

Exit and save the file

This step wasn’t needed, it wasn’t blacklisted:

Now edit the modules blacklist file:

sudo nano /etc/modprobe.d/raspi-blacklist.conf

Add a '#' character to this line so it commented out:

#blacklist i2c-bcm2708

Exit and save the file

​Finally install the I2C utilities

sudo apt-get install python-smbus i2c-tools

Enter "sudo reboot" to restart the pi and now the I2C pins will be available to use

This step I never checked if I had to do, and didn’t do it:

If you are running a recent Raspberry Pi (3.18 kernel or higher) you will also need to update the /boot/config.txt file. Edit it with sudo nano /boot/config.txt and add the text

dtparam=i2c1=on
dtparam=i2c_arm=on

at the bottom. note that the "1" in "i2c1" is a one not an L!

Checking For Connected Devices

At the command prompt type one of these depending on whether you are using the I2C0 or I2C1 port:

sudo i2cdetect -y 0

//or

sudo i2cdetect -y 1

The 7 bit I2C address of all found devices will be shown (ignoring the R/W bit, so I2C address 0000 0110 is displayed as hex 03).

pi@raspberrypi ~ $ sudo i2cdetect -y 1

     0 1 2 3 4 5 6 7 8 9 a b c d e f

00:         -- -- -- -- -- -- -- -- -- -- -- -- --

10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

40: -- -- -- -- 44 -- -- -- -- -- -- -- -- -- -- --

50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

70: -- -- -- -- -- -- -- --

pi@raspberrypi ~ $

Then I tried working with i2cset and i2cget:

pi@raspberrypi ~ $ i2cset -y 1 0x44 0x01

pi@raspberrypi ~ $ i2cget -y 1 0x44

0xc8

But I could only get bytes at a time.