New Reef-Pi Forum as a DIY Subforum!

[robsworld78]

First of all, I would like to congratulate and thank @Ranjib for developing and working hard to make the Reef-Pi stable, safe and reliable!
This takes time and dedication, in addition to a lot of knowledge!

Now I have the vnc working, I have access to Reef-Pi inside and outside my network! I've done all the tests, now it's time for the parts list.

I intend to have:
8 relay-controlled sockets
Temperature sensor
PH monitor

Set up some timers and macros, all of which I have already found instructions on how to do, but I need:

4 metering pumps!

But I only found an explanation, tutorial, schema and parts for just two pumps, with the Reef-Pi pwm, I already searched the old forum, with more than 800 pages and I didn't find it, I would like to have an assembly scheme, tutorial and parts for 4 or more pumps, with PCA9685, can I connect the pumps directly to it or do I need some other module?
Thanks in advance!

I was deceived by the previous message, I wrapped up here with the translator and I was unable to delete it afterwards.

You can use the same instructions for the two Pi pwm pins but the extra two you would use pwm from the pca9685. If you prefer you can use 4 pwm pins from pca9685 instead of the pins from Pi. The pca9685 connects to the SCL/SDA pins on the Pi and then you added a pca9685 driver in reef-pi to use the pins. Once you add the driver in reef-pi you'll have access to all 16 pins when you create connectors for the dosing pumps so select the pins you use.

 

[Cristiano Souza]

You can use the same instructions for the two Pi pwm pins but the extra two you would use pwm from the pca9685. If you prefer you can use 4 pwm pins from pca9685 instead of the pins from Pi. The pca9685 connects to the SCL/SDA pins on the Pi and then you added a pca9685 driver in reef-pi to use the pins. Once you add the driver in reef-pi you'll have access to all 16 pins when you create connectors for the dosing pumps so select the pins you use.

Thank you!
So the pca9685 is only for generating the pwm, and the l293d is the one that will generate the power and speed control?

 

[Cristiano Souza]

@robsworld78
I think I found exactly what I wanted, with ULN2803A, with a simpler and more direct connection, without direction control, only power, I can use two, one powered by 12v, for the motors, and the other with 24v, for my LEDs !
Thank you all!

 

[robsworld78]

@robsworld78
I think I found exactly what I wanted, with ULN2803A, with a simpler and more direct connection, without direction control, only power, I can use two, one powered by 12v, for the motors, and the other with 24v, for my LEDs !
Thank you all!

Looks good. The ULN2803 doesn't handle a lot of current so check the lights don't draw too much. Any Arduino DC module will work as well.

 

[lepetitnicolas]

Hello,

my ReefPi project is almost finished.
He works for 4 months on my new aquarium.
I wanted to add a physical button to trigger a macro.
What is the API syntax for triggering a macro ?

http: //reefpi_IP/api /macros / ???

I want to use my Domoticz server to send this http request to the reefpi.

Thank you

 

[Cristiano Souza]

Looks good. The ULN2803 doesn't handle a lot of current so check the lights don't draw too much. Any Arduino DC module will work as well.

It supports up to 500ma per channel, I've read cases in which they used 2 or 3 channels in parallel to increase this amperage, does this happen?
Can it be done like this?

 

[robsworld78]

It supports up to 500ma per channel, I've read cases in which they used 2 or 3 channels in parallel to increase this amperage, does this happen?
Can it be done like this?

Yeah you can connect multiple outputs for more current just be sure the traces on the PCB can handle it. If you look on page 10 of datasheet you can see an example.

https://www.ti.com/lit/ds/symlink/uln2803a.pdf?ts=1618537173121&ref_url=https%253A%252F%252Fwww.google.com%252F

 

[Cristiano Souza]

Hello friends, I need help with the PCA9685! I connected it with the raspberry following the tutorials, but the reef-pi does not find it, it does not communicate with the drive, I have already activated I2c in the config, and even then it does not recognize, it is necessary to change some file or command in the terminal for the installation and recognition of this drive?

 

[Ranjib]

Hello friends, I need help with the PCA9685! I connected it with the raspberry following the tutorials, but the reef-pi does not find it, it does not communicate with the drive, I have already activated I2c in the config, and even then it does not recognize, it is necessary to change some file or command in the terminal for the installation and recognition of this drive?

once you have enabled i2c and connected pca9685 physically with i2c wires (4 wires involved), you should see the pca9685 address using i2cdetect command, as described in the tutorial. if this is not happening, then its something outside reef-pi code. its either a bad IC or bad connection or some configuration issue.

 

[Cristiano Souza]

once you have enabled i2c and connected pca9685 physically with i2c wires (4 wires involved), you should see the pca9685 address using i2cdetect command, as described in the tutorial. if this is not happening, then its something outside reef-pi code. its either a bad IC or bad connection or some configuration issue.

Thanks @Ranjib !
Problem solved!
I had made many modifications to the rasp files, making tests, mainly in the config!
I was using version 3.0 of reef-pi!
I installed raspbian again, updated the reef-pi to version 4.1 and now everything works normally, PCA9685 detected and working!
Now a question with the temperature sensor DS18B20, to use more than one, 2 or 3, are all connected to GPIO4?
Are they used in parallel?

 

[Cristiano Souza]

Thanks @Ranjib !
Problem solved!
I had made many modifications to the rasp files, making tests, mainly in the config!
I was using version 3.0 of reef-pi!
I installed raspbian again, updated the reef-pi to version 4.1 and now everything works normally, PCA9685 detected and working!
Now a question with the temperature sensor DS18B20, to use more than one, 2 or 3, are all connected to GPIO4?
Are they used in parallel?

I just found the solution to my question, really the DS18B20 sensors are connected in parallel, share the same pins and only a 4.7k resistor!

 

[Ranjib]

I just found the solution to my question, really the DS18B20 sensors are connected in parallel, share the same pins and only a 4.7k resistor!

yes i have tested till 5, know some folks who run 7 sensors. But in operation i run 3 at a time max , for one of the non-reef usage.