DS18B20

[jollybv]

Hi guys

I ordered some probes from china and the ended up being DS18B20, I found the example on wiki but for some reason it will not compile to the esp32, Keep getting warnings and then it fails Could this be something I'm doing or a problem with the 1 wire component?

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[LeighM]

Hi,
Your UART is set to Software mode, this isn't supported on ESP, could you use a hardware channel?

[jollybv]

Hi Leigh

Thanks that worked now to figure out why I'm getting a loads of 0000 probably not connected to the right pin on the esp32 module Is the pin 10 (esp module) Port A25 the correct pin for this?

[BenR]

The OneWire pin can be any of the digital IO pins. Yes it is pin IO25 currently in the example.

Do you have a pull up resistor between A25 and VCC. I used a 1K resistor for my testing and that worked well.

[jollybv]

Hi Ben

The 1K did the job I was using a 47k which i saw on some web site it would work then stop working. Is it possible to use floating values in the PID conversion? say I want to set the set-point to 78.1, 78.2, 78.3 etc

[BenR]

Currently you would have to say multiply everything by 10 so instead of controlling to the degree you would control to the nearest tenth of a degree.

78.1 would therefore become 781.

You would have to divide back down before displaying the number again etc.

I am considering adding a Float buffer type to the DSP components but it's tricky and so far I'm not 100% sure how to do it cleanly.

[jollybv]

Thanks Ben

I will try this and see how I get along