Is there a minimum wake time (ST) when using synchronous sleep mode?


We are using XBee 868 to connect to sensors, some of which are on battery, so we want to minimize the power use.

When building a mesh network (so we set the XBee’s to synchronous sleep mode, SM 8 or SM 7), we try to set the wake time (ST) as short as possible.

It seems like there is a minimum wake time, because when we try to set it to less than 3 seconds it just sets it back to the same value (CA5, or 3237 ms).

The same is true if I try to set it via AT commands.

But I haven’t found anything in the documentation stating a minimum wake time for synchronous sleep modes.

With asynchronous sleep modes we have no problem setting the wake mode to shorter values than this.

Thanks in advance,

868 LP I assume as 868 Pro has been end of lifed.

Page 69 of the manual is what you are looking for:

The ST parameter will automatically adjust upwards to its minimum value when other AT commands are changed that will affect it (SP, and NH).

Close. The NH, BH, and SP time that control the min wake cycle time.