I've been trying to use WS2815 leds in my stairs, but I'm struggling with noises problem.
I'm using stm32f103c8t6 based bluepill board as a controller for 18 1m long led strips. Each strip is controlled separately, using TXS0108E level shifters. Between each pin and led strip there is ~4 meters of 0,35m^2 wire. I've created a board to place all components but there was a a problem with wire capacity, which I solved adding 4k7 pull-ups (green lines) and 100nF capacitors (pink lines). The last problem I cannot overcome are noises (or some capacity, making line unable to go LOW). The problem is, that first pin from power source (first from right) works perfectly, second has a little noise and every next one is worse. Should I use other resistor for pull-up? Or maybe use pull-down instead? Problem does not occur if I connect led strip straight to the board, without the long wire.