displays as unsigned integer why?

[Jan]

The question does not contain enough information to be answered.

[bill buersch]

well the range for a 16 bit integer is

-32,768 to +32,767

however for an unsigned 16 bit integer it is

0 and 65,535 In the picture we see 65535 shown but in fact is -1 because that while the bits are the same, it is being wrongly interpreted by the chart program on the website.

A 16-bit integer can store 216 (or 65,536) distinct values. In an unsigned representation, these values are the integers between 0 and 65,535; using two's complement, possible values range from −32,768 to 32,767.

So i guess my question is there as setting to have 65,535 treated as a signed integer so the chart looks right?

[Geoff Hayes]

@bill buersch perhaps you need to show the code that generates this chart.

[bill buersch]

i can't because it is thingspeak code that generates the chart. it's the chart you get when you log in. it interprets as unsigned when it should interpret as signed. but i see that there is no way it would know.

[bill buersch]

notice that when the outside air temp rises above 0 it's fine.

[bill buersch]

data as stored: 2022-12-21 12:36:13 UTC,1,65535,,,,,,,