We've written a program to get XBee to sleep using async pin sleep mode (SM=1). The XBee is working as expected most of the time (when sleep_rq is asserted, the XBee will go into sleep mode after 1 tick (4ms)).
Our problem is during the start of the program, we have to run node discovery to discover a target receiver node. The receiver node is discovered within a second or two, but after that we could not turn the XBee into sleep mode for around 25seconds. After the 25seconds everything go back to normal. We're suspecting that there's some unknown tx or rx operation in the background thus we could not turn the XBee into sleep mode. Is there any way to sleep the XBee immediately after we discover the receiver node?