ESP Easy DS18B20 Negative temperature error

[VasilijHCN]

Hi, first thanks for great work !!!
I use ds18b20 temp sensor, in positive temperature range all great, when temperature hit in negative range i got 4000 Celsius. I created my own simple esp8266+ds18b20 domoticz sketch, all works without error.

Its possible to control pwm via html request ? (like http://192.168.1.122/control?cmd=gpio,12,1), if yes please tell correct pwm command.

[Martinus]

The negative value should be fixed, although I wasn't in the position of actually testing this. No freezer available in my testlab...
But there was definitely a bug due to a wrong variable type in the code.

Info on direct control of GPIO pins:
http://www.esp8266.nu/index.php/GPIO

[menyiv]

Hi, good code

but this is problem. Some reason for this error?

[ambassadoro]

Double check the cabling and the power source. This often helps alot.

For doing freezing-tests, I use pressurized air in spray cans, use the can upside down and it emitts liquid gas. Be careful! Its flammable.

[VasilijHCN]

// R32 09-10-2015
// Fixed a bug in negative values on Dallas DS18b20 and added CRC check.
I use one external sensor, perfect reading negative temperature. Martinus created great project. If error occurs check pullup resistor from vcc to data pin