MCP4725 and INP12 rev c on raspberry pi 3B+

#1

Hello, I am trying to use my MCP4725 0-10V DAC with my raspberry pi I have the INP12 shield. I cannot get my Pi to recognize the I2C device. I am using i2cdetect -y 1 in my pis terminal. The power light is lit up on my DAC board. Please help. I am really eager to get this working for my school project.

0 Likes

#2

is the i2c enabled?
can you share a picture of the setup.

Thanks

0 Likes

#3

Here is the hardware set up and the commands that I have done

0 Likes

#4

what is the INPI shield REV number?

0 Likes

#5

It is the inpi2 rev c

0 Likes

#6

everything looks good in terms of setup/wiring.
do you happen to have any other pi you can use for a quick test.

0 Likes

#7

I don’t. This is the only pi I have.

0 Likes

#8

do you have any arduino board?

0 Likes

#9

I do have an arduino

0 Likes

#10

if you can give it a try with arduino.
You will need to connect 0-10V DAC SCL ,SDA, Gnd, 5V lines with arduino SCL, SDA, Gnd, 5V pins.
make sure you install pull ups on the 0-10V DAC board.
arduino code can be found here

0 Likes

#11

How do I install pullups?

0 Likes

#12

there are two pull jumpers on the board.


the info can be found in product wiring diagram as well.

0 Likes

#13

Should I be using the pull ups on my raspberry pi? I am currently not.

0 Likes

#14

hi,
the pi shield has on board pull ups.
You can try installing on the 0-10V board.

Thanks

0 Likes

#15

How do I install the pull ups? What do I connect them to?

This is my first time working with anything like this and I don’t fully understand how it works.

0 Likes

#16

Okay. I have tried with arduino. I have not connect the board to my motor because I am lost on exactly what the arduino code is doing. I cannot tell if the DAC board is working or not. It is powered on just as it was with the raspberry pi.

0 Likes

#17

It is doing 4-20mA it appears instead of 0-10 V

0 Likes

#18

you can use this arduino code to scan the i2c devices

the 4-20mA and 0-10V use same chip. so the code is also same.
//for (int i=0; i <= 4096; i++) ///////to use this code with 0-10V Hardware
for (int i=290; i <= 1500; i++) ///////to use this code with 4-20mA Hardware

0 Likes

#19

Hi:

Did you enable I2C on the Pi?

Figured you have. But, needed to ask.

Thanks

0 Likes

#20

Okay, I have enabled i2c on my pi following those instructions. I had already done it but I walked through that to double check. I also used the arduino scanner and it is picking up the device. Is there a way to check if the shield is the problem? I also noticed in the adafruit directions for setting up i2c that it asks you to enable the ARM and then to have the kernel loaded by default. I don’t get the question of whether it should be loaded by default? Is my pi even saving this setting?

0 Likes