Siemens SIMATIC NET PROFIBUS Owner's Manual page 487

Token ring
All the masters physically connected to a bus receive the token and pass it on to
the next master: the masters are located in a token ring.
Token rotation time
is the time that elapses between receiving the ³ token and receiving the next
token.
Transmission rate
The transmission rate specifies the number of bits transferred per second. On
PROFIBUS, transmission rates of 9.6 Kbps to 12 Mbps are possible.
T
RDY
Indicates readiness to acknowledge or respond (ready time)
T
SET
Setup time. The setup time is the time that can elapse between receiving a data
frame and reacting to it.
T
SL
The wait to receive time (slot time) is the maximum time that can elapse while
the sender waits for a response from the addressed station.
T
TR
Target rotation time. Each master compares the target rotation time with the ac-
tual token rotation time. The difference between the two decides how much time
the DP master has available to send its own data frames to the slaves.
PROFIBUS Networks SIMATIC NET
6GK1970-5CA20-0AA1 Release 2 05/2000
Glossary
Glossary-7