SPI first LED is green

Change:
uint8_t tx[num_leds*3*4+3];
To:
uint8_t tx[num_leds*3*4+6];

DONT change:
unsigned spi_ptr=0;

Thanks - that rules out one theory.

can you tell us more about the level shifter ? Do you have a schematic/circuit diagram?

A couple of photos would be helpful.

So the level shifter doesn't seem to make any difference ?

I've had bad experience with those mosfet level shifters with the ws2812 leds and have given up on them.

The last 3 I made I've used 74HCT series chips and they've been flawless.

Just about any 74HCTxx chip can be used if you wire it correctly.

Cool - let me know if you need any help with the parts you have on hand.

74HC won't work due to the input levels being cmos.
74LS is probably too slow
74HCT is juuuuust right

Damn !

So you have a separate 5v PSU for the leds ?

A good ground connection between
- the Pi,
- the 74hct00
- The led strip
- The led power supply

Is the 74hct00 powered by the pi or the led power supply ?

Can you tell I'm running out of ideas ?

I'm beginning to wonder if the 1st led is faulty ?

I wish I could drop by with oscilloscope and see what's happening on the pins !

I can add it easily.

Do you want me to patch the classic original Hyperion or do you want to try the fantastic new Hyperion.ng ?

Assuming you've cloned the hyperion
hyperion/libsrc/leddevice/LedDeviceWs2812SPI.cpp

Line 37: unsigned spi_size = mLedCount * SPI_BYTES_PER_LED + 3;
Change 3 to 6
Line 42: unsigned spi_ptr = 0;
Change 0 to 3

Thats it .... you'll notice the code is very similar!

I do have another theory tho..... maybe your leds arent actually ws2812 but one of the many clones around.
The timing I have for the reset pulse is actually waaaay out of spec, but has worked find for ws2812 and sk6812 leds.
The alternate fix for this to simply extend the reset pulse is:
Line 37: unsigned spi_size = mLedCount * SPI_BYTES_PER_LED + 3;
Change 3 to 80 (yes.... eighty)

same issue here with anything ive tried, than its an OPI issue,
@peter what OPI do you have?, mines an Orange Pi Plus v1.1 on Armbian 5.25 Server
ill be trying this code edit out on the shiny new hyperion-ng and will report back!

Edit : code is fairly different, not exactly into C++ so much; which one should i modify?

unsigned spi_ptr = 3;
    const int SPI_BYTES_PER_LED = sizeof(ColorRgb) * SPI_BYTES_PER_COLOUR;


    for (const ColorRgb& color : ledValues)
    {
        uint32_t colorBits = ((unsigned int)color.red << 16)
            | ((unsigned int)color.green << 8)
            | color.blue;


        for (int j=SPI_BYTES_PER_LED - 1; j>=0; j--)
        {
            _ledBuffer[spi_ptr+j] = bitpair_to_byte[ colorBits & 0x3 ];
            colorBits >>= 2;
        }
        spi_ptr += SPI_BYTES_PER_LED;
    }

in the meantime ill try compiling without edits

Edit 2: Compiling Hyperion-ng, had to modify CMakeLists.txt because it was detecting the OPI as a Raspberry Pi due that the CPU check is not by model but by architecture.
Modified Lines 73 to 75

elseif ( "${PLATFORM}" STREQUAL "rpi" )
    SET ( DEFAULT_DISPMANX   OFF )
    SET ( DEFAULT_WS281XPWM  OFF )

Edit 3 4:

compiling right now

Edit 5 : Compile done, will test in about an hour

const int SPI_FRAME_END_LATCH_BYTES = 3;

Edit: changed video links to webm

sorry to rewake an old thread but i didnt want to start another one

so i tried connecting everything with the SPI with a 74HCT125, ive tried doing the edits on the orangepi and did not have a green led, then i upgraded the orangepi to a devport kernel 4.10 due that video0 was not found on the old 3.4.113 kernel
now i have some glitches, which i suppose are either from timing, the first led gone bust or i have a clone of the ws2812b
I have tried editing /libsrc/LedDevices/LedDeviceWS2812SPI.cpp variable SPI_FRAME_END_LATCH_BYTES with 6 and 80 and unsigned_ptr to 3. In all cases i fixed the first green led, but not this (webmshare).

With the Raspberry Pi 3 and no edits to the , i get something completely different. it works except for this random white flashing, on Dispmanx Grabber , it stays white longer , maybes because theres more white on the first few leds due to the top bar in linux desktop (?)

So close to fix but i always seem to find something in the way