BlinkStick Flex: How to update all 32 LEDs simultaneously? set_led_count(32) lights only first 8 LEDs

[DimaTepliakov]

Hi BlinkStick team,

I’m using a BlinkStick Flex (32 LED strip) with the Python library on Windows, and I’m trying to light all 32 LEDs at the same time.

Current Behavior

Using set_color() in a loop works, but LEDs update sequentially (one-by-one):

for i in range(32):
    bs.set_color(channel=0, index=i, hex="#00FF00")

This results in visible delay / sweep effect.

Attempt to enable bulk update

I noticed the device exposes set_led_count(), so I tried initializing the device like this:

bs.set_led_count(32)

After doing this, when I attempt to light LEDs, only the first 8 LEDs turn on, and the remaining LEDs stay off.

Example:

bs.set_color(hex=hex_color)

Result:
LEDs 0–7: ON
LEDs 8–31: OFF

So my current solution is:

bs.set_color(hex=hex_color)
for i in range(8, 32):
   bs.set_color(channel=0, index=i, hex=hex_color)

Questions

1. What is the correct way to update all 32 LEDs simultaneously on BlinkStick Flex?
2. Is there a frame / bulk update API (single USB transfer) intended for this use case?
3. After calling set_led_count(32), is there an additional required step (mode, report type, data format, etc.)?
4. Why does set_led_count(32) appear to limit output to 8 LEDs when using set_color()?

Environment

Device: BlinkStick Flex (32 LEDs)
OS: Windows
Python: 3.10
blinkstick package: 1.2.0

Thanks!
Any guidance or example code would be really appreciated.

[p0ke234]

Hi @DimaTepliakov,

did not work with it for years but afaik there were limits to 8 LEDs with some commands.

The following small example using set_led_data and sets 10 LEDs to red.

from blinkstick import blinkstick
import time
bstick = blinkstick.find_first()

bstick.set_led_data(0, [0,255,0,0,255,0,0,255,0,0,255,0,0,255,0,0,255,0,0,255,0,0,255,0,0,255,0,0,255,0])

The device need to be in mode 2.