MMM-PiLights - Control a LPD8806 Led Strip on a Raspberry Pi

jc21

Specifically for MagicMirrors on a Raspberry Pi with a LPD8806 led strip, this module allows other modules to trigger light sequences or trigger from a http endpoint.

github/jc21/MMM-PiLights

KirAsh4

May I suggest you add a section on how to actually connect the LED strips to the pi, which pins, etc.? Not everyone is as technical as some of us …

jc21

This guide should cover it. Although that is for older raspberry pi models but still worth a read.

For raspberry pi 3 I’ve connected the pins [DI to 20] and [CI to 24] as labelled in this image.

KirAsh4

I’m referring to adding it to the repository README.md file.

KirAsh4

And technically speaking, the LPD8806 chipset requires 4 wires for input: VCC, GND, DATA_IN (DI), and CLOCK_IN (CI). On a Raspberry Pi 3, the SPI port is on pins:

MOSI    P1-19  (Master Out Slave In)
MISO    P1-21  (Master In Slave Out)
SCLK    P1-23
GND     P1-25
CE0     P1-24
CE1     P1-26

For DATA_IN, you should use the MOSI (19) pin, and for CLOCK_IN, the SCLK (23) pin. Pins 24 and 26 are chip select pins if you happen to have several SPI slave devices and needed to select which one you’re addressing.

jc21

Ahh you are correct that is how I have it connected, I just had a dyslexic moment and named the opposing pins by accident

schmo90

Hy

i changed your module to work with the common W2801 Led Strips.

Now i wanted to add some new sequences.
I modified the switch case but everytime i will go to this sequence with the http request i get the answer, squence not found.

this.expressApp.use(bodyParser.urlencoded({extended: true}));

    this.expressApp.get('/PiLights', (req, res) => {
        console.error('[PiLights] Incoming:', req.query);

        if (typeof req.query.sequence !== 'undefined') {
            // Sequence

            this.runSequence(req.query.sequence)
                .then(function () {
                    res.status(200)
                        .send({
                            status: 200
                        });
                })
                .catch(function (err) {
                    res.status(400)
                        .send({
                            status: 400,
                            error: err.message
                        });
                });

        } else {
            res.status(400)
                .send({
                    status: 400,
                    error: 'Sequence not specified'
                 });
        }

So if i send a new sequence then i will get the answer 400 sequence not specified.
Where do you specify the available sequences?

With Best regards
Schmo

jc21

Hi schmo90, good to see you’re contributing

Assuming your tests with curl -X GET "http://yourmagicmirror/PiLights?sequence=blue_pulse" still don’t work, I think I’d need to see all of your changes. If you’ve forked my repo on github can you please link it?

schmo90

Hy

yeah i made a infinite mirror behind the magic mirror

your animations are working fine with my change of your led strip class to my w2801 class.
But if i add some squences in the switch case, for example ‘off’ then i get the request error.

is there some hidn node.js thing where you define the possible sequences?

I have to say i am a C# developer and it is the first time with node.js…
No debugging and intellisense with nano is realy painfull^^

jc21

@schmo90 It should work fine, there is no logic prior to that switch that filters possible values.

What does the server console log report after the text [PiLights] Incoming: ?

req.query.sequence should contain the string name of the sequence you’re requesting.