Issue: Switches would only throw intermittently when controlled by a macro.

Just a quick note to let you know of an issue that I have become aware of and how to fix it.

I have a 12 road fiddleyard / staging for Phase 1 of my layout (see plans). Roads / routes are set through 12 macros.

The issue was that switches 19 and 20 would only throw intermittently when being controlled by a macro. There was no problem when thrown individually. The two swicthes were both controlled off of the same Digitrax DS52 accessory decoder.

I reporgrammed the accessory decoders, used a different Digitrax DS52 accessory decoder, reprogrammed the macros and all to no avail.

Because of the number of switches I need to throw on two of the roads, I needed to use nested macros. I even tried including the two switches on one simple macro with no other commands but was still getting the same problem.

I emailed NCE but NCE did not reply. Tut Tut.

Fix: I included one of the switches on the top level macro and the other switch on a nested macro.

 

Possible Non-Technical Explanation:

I cannot verify if this is true as NCE have not replied to my query. However, after posting the issue on the Yahoo NCE forum, I received a reply stating that NCE macros send commands to all accessory decoders at the same time.

There is a potential issue with some accessory decoders when a decoder is used to control two switches and both switches are included in the same macro.

The accessory decoder may become 'over-loaded' when commands for both accessories are sent at once to the same accessory decoder (in this case a Digitrax DS52 ) causing one set of commands to get rejected / lost.

The commands for each switch need to be separated so as they do not reach the (same) accessory decoder at the same time; this was achieved by programming one switch in the main macro and programming the other switch controlled from the same DS52 in a nested macro.

All macros now seem to work consistently without any trouble and have been doing so since the first week in Janury (2008). It should also be noted that I have not had similar issues in "overloading commands " with either the CML DAC10 or the Digitrax DS64.