I put CC1110 to PM2 and wake it up by the sleep timer. In my opinion, the WOR will start automatically (In AN047, it's said that WOR is done without MCU interaction) when the sleep timer triggled.

Since can not find the SWOR strobe command in datasheet,I just turn the radio on to RX after CC1110 wakes up from PM2 in my test. However the IRQ_TIMEOUT interrupt never happens. It looks like the chip does not enter WOR mode.

So when and how the chip starts the WOR?