The new XTB-IIR firmware has three AGC sample points. Like the prior versions, there are optional sample points before and after the X10 transmission window. This version adds a third sample point during the X10 reception window when it is receiving a logic “0”. I found that improved the response to my “triple CFL” noise generator.
While testing this code, occasionally a command would not be repeated. After spending hours trying to track down a bug in the code, I discovered it was my remote RR501 occasionally transmitting with 50Hz timing. I had forgotten they sometimes do that, and it plops the third signal burst just before the zero crossing when that AGC sample is made. That caused the detection threshold to rise, missing some of the following bits. (I’m testing with very weak signals at this point.) This could be a factor for some folks having trouble repeating transceiver commands.
The previous fix was to choose the alternate AGC sample point, but this version will ignore that sample when receiving a powerline X10 command. This version also has individual mode options to enable the pre and post X10 window samples. Both are enabled by default.
The detection threshold query (9 – 8 – 2 – DIM) is working well, and transmits the threshold (1-30) as a pre-set dim command. The XTBM will display that as a percentage.
I chose not to transmit all the mode settings as a sequence because that would require some sort of logger. One of my customers wrote a nifty utility using the AHP SDK to query and set the mode options, and I think that is a much better option. However, I did add a manual query. Just entering the mode select (9 – 8 – 2 – X) will cause the LED to either blank or become bright for first half of the 4-second ON/OFF mode command window. So that allows one to easily check the current setting of an individual mode status.
One new feature that has been added is the ability to inhibit repeating certain house codes. That could come in handy when two neighbors on the same utility transformer are using X10 systems.