mpleeds wrote:I ended up purchasing the Phidgets 1019 interface kit and 1124 temp. sensor and got it working with WebService, but unable to connect via USB. With WebService configuration, I am unable to adjust "sensor data rate settings" which is critical to my application in reading sauna temp. changes. After going through the plugin discussion, I found the post which explains that Data Rate settings...
The data rate of a Phidget InterfaceKit port (libs v2.1) is the interval in ms at which the analog port is read. When used via the Web-Service it is fixed at 16ms. Thus, each analog port will be read 62.5 times per second (1000/16). On each read, the value (0-1000) returned is compared to the trigger value and if the difference between the last reported value is greater than the change value it will be reported via the Web-Service. I do not recall offhand the exact specifications on the 1124 but I seem to recall it can measure between -30ºC and +80ºC, a range of 110º. Divide 110/1000 and you get each step (0-1000) is equivalent to 0.11º. Therefore, a change of 9 = around 1ºC.
So, if you set your trigger for 9, then the phidget will check 62.6 times per second for a change of 9 since the last report. Ie. it will check 62.5 times per second to see if the temperature has changed 1º since the last change report. If you want greater granularity, set the change trigger lower. 3 would be 0.33 degrees. However, be careful. The 1124 is not super stable and if you set the change trigger to low, it will thrash constantly.
Given your use in controlling a sauna (great application BTW, from a sauna lover) I would think there is no need to measure more often.
BTW, you should be able to read the phidget directly, but I really recommend against doing that. A direct read of the USB will block the phidget and you will not be able to see it via the control panel.