Is there a way to use frequency hopping without needing to plan 2 hops in advance?

Question

It appears as though CHANNEL_SETUP must be asserted 2 HOP edges ahead of time to define whether that hop will be Tx or Rx. In our system, it is not known whether the next hop will be a Tx or Rx until the very end of the previous hop. Is there a way to operate the XCVR in this way? 
 As a work around, I could potentially pulse the HOP signal, instead of simply toggling it (ensuring I provide 0.42 us of setup/hold to the TX/RX_Setup signal). That would essentially interrupt the retune and begin a new one shortly after initiating it (and the hop table would have to have 2 entries for each hop). 
 I understand that sounds pretty hacky, but is it feasible? Is there a way to make this work? 
 
 Thank you

RahulMushini · Accepted Answer

Hi, 
 There are two mode for FH i.e., PLL Retune and PLL MUX mode. 
 The channel enable pin must be rising before the HOP edge to determine whether the current frame is rx or tx. As you can see from the below timing diagram taken from the user guide. For Frame 0 the Rx pin is high before the HOP rising edge determining that the Frame 0 is Rx and in the next frame 2 the tx pin is high before the HOP falling edge determine the that Frame 1 is Tx. It is not required to CHANNEL_SETUP to asserted 2 HOP edges ahead of time. 
 Note: HOP signal rising and falling edge along with the Tx/Rx rising edge is used for determining the if channel has to be tx or rx. 
 
 One has to be careful with the transition time which is minimum time required to set up the Rx or Tx channel and switch to a new operating frequency. For less transition time one can use the MUX FH mode since two PLLs are used whereas LO retune mode will have more transition time since only one PLL is used and a single PLL is used for returning for different frequencies. 
 
 As suggested in the user guide for PLL retune FH mode, once the previous frame ends the PLL will start to retune for the next frame. Hence to answer your question it is possible to setup the channel for tx and rx mode when you have the information at the very end of the previous hop but the transition time will be longer. 
 Regards 
 Rahul)

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Is there a way to use frequency hopping without needing to plan 2 hops in advance?