Siemens Sinamics S110 Function Manual page 645

Start delay
The duration of the start delay must at least be as long as the time for two characters and
depends on the baud rate.
Table 9- 44
Baud rate in
bits/s
9600
19200
38400
57600
115200
Note: The time between two characters must be shorter than the start delay.
STX
The STX block is a single-byte ASCII STX character (0x02) and indicates the beginning of
the message.
LGE
LGE is a single-byte block and specifies the number of bytes that follow in the telegram. It is
defined as the sum of
● User data characters (quantity n)
● Address byte (ADR)
● Block check character (BCC)
The actual overall telegram is, of course, two bytes longer because STX and LGE are not
counted in LGE.
Function Manual
Function Manual, 01/2011, 6SL3097-4AB10-0BP3
Duration of the start delay
Transmission time per character
(= 11 bits)
1.146 ms
0.573 ms
0.286 ms
0.191 ms
0.059 ms
9.5 Communication using USS
Transmission time Min. start delay
per bit
104.170 µs > 2.291 ms
52.084 µs > 1.146 ms
26.042 µs > 0.573 ms
17.361 µs > 0.382 ms
5.340 µs > 0.117 ms
Communication
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