Hello,
When a master using CC2540 calculates the ChM field that appears in CONNECTION_REQ LL message, what is the power value against which it decides that a channel can/cannot be used?
Thanks,
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Hello Greg,
Thank you for your reply. Do you mean that the controller has no role in determining ChM in CC2540?! What if a very simple application was developed that pays no attention to this task and instead relies on the expected functionality of the Link Layer, how will the Link Layer decide what value of ChM to include in CONNECT_REQ messages?
Regarding your suggestion about PER stats, it is to my understanding that two consecutive packets received with an invalid CRC match within a connection event shall close the event. That will not allow for PER to grow for a given data channel index since the event is closed and a new event is started.
My question is targeting the specific power threshold that will render a channel unusable for the system when it calculates ChM.
Thanks again,
Omar
CC2541 Master LL will use all 37 channels in CM by default. Connection will stay up unless no packets are received before supervision timeout. The channel will increment to next channel (current channel + hop) . It is true, that using PER will require some time to collect data across all CM channels.
BR,
-Greg
I find this quiet strange! To my knowledge, there's nothing in the standard that suggests that there's a default value for ChM. What about the scenario when a connection is to be started in the presence of WiFi interference on Ch6 for example, according to your explanation the ChM field will contain all 1s regardless of the interference and then only update ChM later on (which will require LL_CHANNEL_MAP_REQ procedure that states the possibility of a host updating ChM without being instructed by the Host) if the developer wanted to in his code!
Thank you for taking the time to answer my questions.
Omar