If you want to power the Pi via USB instead be sure to connect the Ground of the strip with ground of the pi.

The GPIO ground or the power ground going into USB-C?

thanks

the pin is tall.

The reason is that the output of the RPi can drive a handful of LEDs, but the Pi only has so much power flowing through it (specs say 50mA). Powering the LEDs separately will let the Pi handle the logic and the power supply handle the… well, power.

Thanks @bhepler I understood that the LEDs must be powered by an external 5V because the RPI generates a few mA and is not able to turn on an LED strip, but from the photo you can see that the external 5V (+ and -) also goes in parallel on the 5V in exit from the RPI.

For what reason?
Is this connection necessary (I no longer have 5V available on GPIO …)?

Thank you very much

I have seen the connection between RPI and LED strip but I do not understand why the external 5V power supply must also be connected to the RPI, is it not enough to connect it to the LED strip?

The reason is that the output of the RPi can drive a handful of LEDs, but the Pi only has so much power flowing through it (specs say 50mA). Powering the LEDs separately will let the Pi handle the logic and the power supply handle the… well, power.

For the LED-Strip… i use a WS2812. Its adessable an u can use it with 5V and it preconfigured in Hyperion

Where did you buy the LED strip? They seem very expensive …

I have seen the connection between RPI and LED strip but I do not understand why the external 5V power supply must also be connected to the RPI, is it not enough to connect it to the LED strip?

If I really have to connect the power supply to the RPI as well, how do you do if you have both PINs of the 5V GPIO occupied?

For the LED-Strip… i use a WS2812. Its adessable an u can use it with 5V and it preconfigured in Hyperion.

In the meantime, can you tell me an LED strip (not necessarily RGB …) that is compatible with this project?

Thank you all.

If your using any smart home software as well… this should be an easy thing. Feel free to ask…

@Egnos ok got it.
what I was saying is that the
MMM-PIR-???
modules, if you use them, THEY send the USER_PRESENCE notification
the GPIO_Notifcations module is more generic and can send notifications for ANY gpio device

Ok ok, I just wanted to be sure that, in my case, the MMM-GPIO-Notifications module sends the “USER_PRESENCE” notification.
I knew that the module I am using is a collector of GPIO devices…

Thanks @sdetweil

what I was saying is that the

MMM-PIR-???

modules, if you use them, THEY send the USER_PRESENCE notification

the GPIO_Notifcations module is more generic and can send notifications for ANY gpio device

u don’t need the GPIO_Notifications module. as the PIR modules send the USER_PRESENCE notification:

The module I use for sending notifications when the PIR detects motion is MMM-GPIO-Notifications
I believe he is sending the “USER_PRESENCE” notification:

notifications: [
            {
              notification: 'USER_PRESENCE',
              payload: true
            },

Thanks for your patience @sdetweil ! ;-)

use my updated fork…
https://github.com/sdetweil/MMM-PiLights
it responds to the PIR modules USER_PRESENCE notification (true = turn on, false = turn off)
if lights are off and on is sent, it will restore the previous sequence set with the normal
SEQUENCE notification

Thanks @sdetweil

Let’s see if I understand:

• By default the LEDs will be off, until the “MMM-GPIO-Notifications” module detects something.
• If the PIR detects the movement the “MMM-GPIO-Notifications” module will send the notification USER_PRESENCE = true and the LEDs will turn on
• After some time without movement the “MMM-GPIO-Notifications” module will send the notification USER_PRESENCE = false and the LEDs will turn off

Correct?

I’m not a developer, but I’m still trying to understand your change in the code:

else if (notification === ' USER_PRESENCE'){
            if(payload == false){
                this.leds.allOFF();
            } else {
                // user present, restore the last active sequence
                Promise.resolve(this.runSequence(this.lastSequence.sequence, thi,lastSequence.iterations,this.lastSequence.delay)
                .catch((err) => {
                    this.log('user present Sequence error: ' + err.message);
                }));

why can’t I see this notification in the code?

(notification === ' USER_PRESENCE'){
            if(payload == true){
                this.leds.allON();
            }

Thanks again!

I would suggest the solution of @sdetweil as well.

An other, but much more complicate version would be to use my PythonLedControl and control it with the MMM-MQTTbridge module.

https://github.com/sdetweil/MMM-PiLights

it responds to the PIR modules USER_PRESENCE notification (true = turn on, false = turn off)

if lights are off and on is sent, it will restore the previous sequence set with the normal
SEQUENCE notification

but this module rpi-leds, only toggles the leds ON the pi board… not led strip…

Maybe this module could fit https://github.com/jc21/MMM-PiLights, using SPI and a LPD8806 or WS2801 LED strip.

@sdetweil said in PIR sensor to turn on LED strip:

if u can find one that works the ed strip with a python command, then we can make that work

It appears to respond to notifications:

this.sendNotification('PILIGHTS_SEQUENCE', 'blue_pulse');