What is the difference between a coordinator and an endpoint?
The SubGig standard defines a very simple star topology where one
coordinator device speaks to multiple endpoints. The coordinator is
generally controlled by a host processor, typically on a gateway
connected to the cloud. A device acting as a coordinator generally does
not sleep meaning it is always listening for events from endpoint
devices and is always ready to send a message to an endpoint initiated
from the host.
Endpoints, unlike coordinators, are often battery powered and utilize
sleep mode. The endpoint can only talk to the coordinator and thus no
addressing is required when messages are sent from an endpoint. In
contrast, the coordinator must specify which endpoint it is speaking to
and thus each message from a coordinator will start with the endpoint
ID.
This topology was designed with simplicity in mind so that small wireless networks can be created with minimal configuration.
Related Articles
Can the coordinator queue one message for each endpoint, or does it only queue one message in total?
There is a single slot in the queue for each registered endpoint. Thus, multiple endpoints may have queued messages simultaneously, but only one message can be queued for each endpoint at any given time.
In order to save power, can the coordinator send a PL command over the air to each endpoint?
No this is not a way to remotely change the power level. Also, we do not allow coordinators to dynamically change the listen window for endpoints. The reason for this is that a sleepy endpoint is typically battery powered and dynamically extending ...
The manual mentions that in sniffer mode, the device ID is reported “of the associated endpoint” (6.4.2.3). Does that mean it cannot sniff message from other coordinators?
Yes, it will sniff out any packets whether it comes from a coordinator or endpoint. The sniffer is a special diagnostic mode and thus is not operating as either a coordinator or endpoint itself.
Does the coordinator need to have its sleep mode enabled to send queued packets to sleepy endpoints?
No and you typically don’t want to put the coordinator into sleep mode. When the queue packet command is used the coordinator will check to see if the endpoint is sleepy, and if it is not then it will send the message immediately. In other words, the ...
If I only used AT sleep mode command without SLEEP_RQ, coordinator still receives STA 0001, is this behavior right?
The sleep mode command ATSM will enable or disable sleep mode, but does not put the device to sleep. If an endpoint has sleep mode enabled but it is not sleeping then the coordinator should not receive the STA 0001 (sleepy endpoint) status message.