| ??? 04/18/08 06:28 Read: times |
#153659 - ARP possiblities Responding to: ???'s previous message |
Erik Malund said:
nope, it's quite fast. With the proper algorithm you can 'find', say, 64 slaves (each with a 48 bit address) in about 2 seconds. Then assign them an 8 bit 'node address' Clearly that would force some more complex protocol, with the baggage that brings with it, as polling is, under such conditions, far too time-consuming. the remainder is based on 48 bit node address, max 250 nodes (with random 48 bit addresses changed by a boot routine to 1 byte) Once you have your "node list" it does not need to take more than the time for 2 bytes out and 1 byte in to poll. I am not looking over to poll 10billion addresses , or more but the slaves which are at fixed locations must tell their presence to the master once the Slaves hear their beloved master or masters are there . ARP looks promising as stated by" Jack " somewhere . How big is the collision risk here ? . The process clearly requires the masters to keep silent and listen all the time . Any insight . Erik you have said some thing regarding the "wind stuff" that the slaves finally wind to a one slave what was that? . Richard said:
Given that you have 10 billion possible addresses, and know nothing about which ones might or might not be used on your syste, how long does it take this scheme to ferret out all the possible stations at 8 kbps (a maximal rate limit common in low-cost RF hardware)? Therefore we cannot poll them either , hence the reality :) . Ap |
