This is article 8 of 8 in a series about robust DS18B20 / 1-Wire system design. Please see the introductory topic: [image] DS18B20 Error +85°C / -127°C – Causes, Analysis, Fixes and Reliable Reading Methods Programming This is the main article of a series of 8 …

This post serves as the official Solution of DS18B20 Optical Feedback – Visualizing Conversion Time with an LED (former title). For the full content, see my original post at the very beginning of this thread.

[image] Wawa: First the tens as 20ms pulses with 400ms in between, then a 600ms pause, and then the units with the same pulse/pase duration. I am facing terrible difficulties to draw timing digarm for the above statemnet. Please, help.

Temp of 25C = 2 short flashes, short pause, five short flashes, longer pause, repeat. Leo..

25 . . _ _ _ . . . . . Simple... Tom.... :smiley: :+1: :coffee: :australia:

[image] Wawa: Temp of 25C = 2 short flashes, short pause, five short flashes, longer pause, repeat. On-delay-Off On-delay-Off <---Off----> 5x On-delay-Off <------2 x Off------>

[image] robtillaart: but this "screams" for a performance comparison Here you go: DS18B20 Reliable Reading Methods – Practical Implementation to Avoid Errors and Invalid Values

Practically, there is no benefit in reading the sensor more often that once every five seconds or so. sensor body and copper of the wiring or circuit board takes time to equalise. Leo..

[image] Wawa: Practically, there is no benefit in reading the sensor more often that once every five seconds or so. If the sensor's purpose is to detect possible fire break, then how often should the sensor signal be read?

Do you think this sensor would be a good possible fire break detector?

NOT all sensors could be used to detect possible fire break.

DS18B20 Conversion Time Problems – Visualize Sensor Timing with LED (Debug Method)

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InquisitiveMind March 12, 2026, 12:49pm 36

You were absolutely right: DS18B20 Reliable Reading Methods – Practical Implementation to Avoid Errors and Invalid Values

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DS18B20 Conversion Time Problems – Visualize Sensor Timing with LED (Debug Method)

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