ZNB – Channel Bits setting with remote commands

Description

I am using the command “CONT:AUX:C x” to see when a channel is active. But the respective pin at the AUX connector does not switch to “high”.

Resolution

There are two possible reasons:

The command must be sent exactly at that time when the channel is active, means the ZNB performs the sweep for this channel. There is no problem if just one channel is used.

If more than one channels shall be used, the correct assignment can be done as follows.

Create a new channel and sent the command directly afterwards, see example:
CONF:CHAN2:STAT ON; CONT:AUX:C y

Note that channel 2 is still not active. For that a trace must be assigned to the channel:
CALC2:PAR:SDEF 'Ch2Tr1', 'S11'

Now the pin(s) become high when a sweep for that channel is performed.

Attached are two example plots of the output pin. Only for channel 1 a channel bit was activated.

Just one channel is active:

Two more channels have been added, without activating channel bits. You can see that the “high” time is about 1/3 only. If you measure with a volt meter you may get the impression that the “high” state is not reached.