Siemens SIMATIC NET PROFIBUS manual Access Techniques, Token BUS/Master-Slave Method

PROFIBUS NETWORKS

1.2.2Access Techniques

TOKEN BUS/Master-Slave Method

Network access on PROFIBUS corresponds to the method specified in EN 50170, Volume 2 “Token Bus” for active and “Master-Slave” for passive stations.

				Token rotation
Master		Master	Master	(logical ring)		Master
				Master
	Slave	Slave		Slave		Slave	Slave
	Master = active node				Logical token ring
	Slave = passive node				Master-slave relationship

Figure 1-1 Principle of the PROFIBUS Medium Access Technique

1-8	PROFIBUS Networks SIMATIC NET
	6GK1970-5CA20-0AA1 Release 2 05/2000