Technical data

Setup time (TSET): Minimum "dead time" between the reception of an
acknowledgment before sending a new call frame by
the initiator (range of values: 1 to 255 bit times
*
) (see
Table 6.1).
Minimum station
delay (min TSDR):
(Minimum protocol processing time)
A remote responder must not send an acknowledgment
of a received call frame until this time has elapsed. The
smallest time between receiving the last bit of a frame
before sending the first bit of the next frame (range of
values: 0 to 255 bit times
*
) (see Table 6.1).
Maximum station
delay (max. TSDR):
(Maximum protocol processing time)
An initiator must wait at least this time after transmitting
before sending a further call frame. The largest time
between receiving the last bit of a frame to transmitting
the first bit of the next frame (range of values: 1 to 1024
bit times*) (see Table 6.1).
Target rotation
time (TTR):
Preset target rotation time within which the token must
pass round the logical ring. When the token is received,
this time is constantly compared with the actual token
rotation time already elapsed. This comparison decides
whether and which frames can be sent by the station
(refer also to Section 2.2.2) (range of values: 3000 to
1048575 bit times
*
). This time must be matched to the
requirements of the bus system (for calculation, see
Appendix).
GAP update
factor (G):
After the time "G * TTR" has elapsed, a free address
area between two active stations (GAP) is checked by
the station with the lower address to see whether a
further station wishes to enter the logical ring (range of
values: 1 to 100).
You must match this factor to the requirements of the
bus system. (see Table 6.1).
* Bit time
This is the time required to transmit a bit (reciprocal of the data rate in bps). The unit "bit time" has the advantage that the
parameters are not dependent on the transmission speed used.
To calculate the time in milliseconds from the number of bit time units, use the following formula:
time (in milliseconds) = number of the bit time units / transmission rate (in Kbps).
B8976060/02 Basics of Configuration
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