# LEDs Flashing with Segments **URL:** \ **Category:** Issues\ **Created:** [May 4, 2020, 9:56pm UTC](https://wled.discourse.group/t/leds-flashing-with-segments/394 "2020-05-04T21:56:06Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![tonyno](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/tonyno/32/242_2.png) [@tonyno](https://wled.discourse.group/u/tonyno)\ **Post date:** [May 4, 2020, 9:56pm UTC](https://wled.discourse.group/t/leds-flashing-with-segments/394/1 "2020-05-04T21:56:06Z")
When I created some segments to play with the other day, I noticed that all effects had ~1 second flash to them (091). Doing some more testing today (010), I found that if I select Segment 0 and choose ColorLoop, it’s smooth (no flashing). If I select Segment 0 _and_ 1, they are _both_ smooth. Ideas? More testing data? ---
**Author:** ![Aircoookie](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/aircoookie/32/2_2.png) [@Aircoookie](https://wled.discourse.group/u/Aircoookie)\ **Post date:** [May 5, 2020, 2:15pm UTC](https://wled.discourse.group/t/leds-flashing-with-segments/394/2 "2020-05-05T14:15:47Z")
Hi, make sure the segments don’t overlap. Flashing typically happens if multiple segments try to draw to the same LEDs. Most effects now use a shared refresh rate so this issue will be less obvious, Solid is the most notable exception. My recommendation is to set the stop LED of Segment 0 and then create Segment 1, which will fill the rest of the LEDs πŸ™‚ ---
**Author:** ![tonyno](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/tonyno/32/242_2.png) [@tonyno](https://wled.discourse.group/u/tonyno)\ **Post date:** [May 5, 2020, 2:35pm UTC](https://wled.discourse.group/t/leds-flashing-with-segments/394/3 "2020-05-05T14:35:48Z")
Interesting. Set the Stop of Segment 0 to what? UPDATE! I made Seg 0 0-1 and then Seg 2: 1-11. All good! TY! Even better: For some reason, I thought Segment 0 was special and had to be the whole strip. Not! ---
**Author:** ![Aircoookie](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/aircoookie/32/2_2.png) [@Aircoookie](https://wled.discourse.group/u/Aircoookie)\ **Post date:** [May 5, 2020, 3:54pm UTC](https://wled.discourse.group/t/leds-flashing-with-segments/394/4 "2020-05-05T15:54:38Z")
You are not the first πŸ˜› DrZzs also thought so on his first stream about 0.9. Probably because people usually count from 1 but programmers don’t πŸ˜‚ ---
**Author:** ![tonyno](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/tonyno/32/242_2.png) [@tonyno](https://wled.discourse.group/u/tonyno)\ **Post date:** [May 5, 2020, 4:04pm UTC](https://wled.discourse.group/t/leds-flashing-with-segments/394/5 "2020-05-05T16:04:41Z")
Next hurdle: How can 0-1 and 1-2 not overlap. 🀣 ---
**Author:** ![Aircoookie](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/aircoookie/32/2_2.png) [@Aircoookie](https://wled.discourse.group/u/Aircoookie)\ **Post date:** [May 5, 2020, 4:11pm UTC](https://wled.discourse.group/t/leds-flashing-with-segments/394/6 "2020-05-05T16:11:21Z")
Another thing not really intuitive for us mere mortals πŸ˜‚ The stop led is not included in the range. This is so that you can do `stop - start` to get the segment length. So 0-1 is actually only the first LED. In hindsight I should have implemented this differently, but I wanted the API and the frontend to align as to not cause confusion. It still does πŸ˜„ ---
**Author:** ![tonyno](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/tonyno/32/242_2.png) [@tonyno](https://wled.discourse.group/u/tonyno)\ **Post date:** [May 5, 2020, 4:15pm UTC](https://wled.discourse.group/t/leds-flashing-with-segments/394/7 "2020-05-05T16:15:32Z")
I updated the wiki. πŸ˜ƒ