Friday, April 27, 2012

Real-time telemetry and graph value lookup

I just finished installing an upgrade on I had forgotten a configuration change that needed to be done with this upgrade, and the web service stopped working at 19:16 UTC. I had some trouble finding the problem, and managed to fix it at 19:38 UTC. That was completely unnecessary, sorry for the trouble. It should have been a routine upgrade requiring only a minute of downtime or so. Data collection was not interrupted.

The upgrade made the telemetry graph page update itself automatically as new values come in from the station, just like the weather page does. Just look up a telemetry station and leave the graph page open and the contents will be magically updated!

The grapher engine got a little upgrade which enables graph value lookups on all graphs. Just hover the mouse cursor above a graph and the labels will display the values reported at that time. While the pointer is between reported values it will display an interpolated value.

The real-time map's data refreshing algorithm got some updates and fixes.

I did a few updates on strings too, and the translations need to be updated. At least on the moving stations page I had to split a very long string to two short ones.

Thursday, April 12, 2012

Telemetry display improvements

After attaching some 1wire temperature sensors to the USB port of my D-Link DIR-825 WLAN router running OpenWRT, and making aprx transmit the temperatures in the new base91 comment telemetry format, I felt like improving the telemetry display on a bit.

Current telemetry values are now shown in the info balloon of a station on the real-time map.

I always thought that many telemetry transmitters are only utilizing a few channels, and the other channels should not be shown. So here goes, now you can configure which channels are shown. If any channel names have been sent using the "PARM." message, only those channels (and bits) are displayed in the current telemetry values summary. If no names have been sent, all 5 analog channels and 8 bits are shown.

The telemetry coefficients transmitted with the EQNS. message now stores 5 decimal digits instead of 3. Base91 comment telemetry supports 13 bits of resolution (values 0 to 8280), which often needs to be scaled down to a range such as -55...+125C for temperature. More decimals in the multiplier and exponent parts help in making it accurate.