Folks,
Here is an explanation for what is going on. I will try to keep this as non-technical as I can...
Most monitoring applications, regardless of whether they are for Linux or Windows (or both), suffer from a well-known problem: while they might understand how the SIO device works, they do not understand how the SIO device is being used on a particular board. This can manifest in many different ways. Here are a few examples:
- There may be sensors in the SIO that are not being used. This is the case we have here; the SYSTIN sensor is not used (not connected to an external diode/thermistor and thus returns garbage readings). In the case of the WY NUCs, this is because we are using the NCT5577 SIO and, in this particular device, this sensor is not bonded out to an input pin (I would use it if I could!).
- There may are sensors that share input pins and only one of the two sensors can actually return valid readings (depending upon what input is provided). For example, in the case of the NCT6776/NCT5577, the AUXTIN temperature sensor and the VIN3 voltage sensor share an input pin. If a diode/thermistor is connected, the AUXTIN sensor shows good temperature readings and the VIN3 sensor shows garbage voltage readings. If a voltage input is connected, however, the AUXTIN sensor shows a garbage reading and the VIN3 sensor shows a valid voltage reading. Note: in our case, we use this input for a temperature.
- In the case of voltage sensors, the Analog to Digital Converter within the SIO can only support voltage inputs that are (in this case) less than ~2.2V. If you want to measure a voltage that is higher – the 5.0 volt rail for example – you have to divide down the voltage to some value below 2.2V before inputting it to the device (this is done with pull-up and pull-down resistors). When you read the reading from the sensor, you must multiply them up by the same amount that the resistor array divided them down before you will see a correct value. If the application doesn’t understand the divider being used on a board, it won’t know how to multiply the value and thus displays what appears to be a garbage value. This too is an issue that you folks are seeing (but perhaps didn't catch).
These applications need to have support added to them for a database that explains how each board works. This is problematic, I know, because boards come and go, but there is no other way to handle this that I know of...Image may be NSFW.
Clik here to view.
...Scott
P.S. I generate documents that explain how we use the SIO (and other monitoring devices) on our various boards -- and have them covering boards all the way back through our 6 Series Intel® Desktop boards. If you are a developer for any of these applications, let me know and we can arrange to get these documents released to you...
