Timing Of The Communication - JUMO LOGOSCREEN nt Interface Description

4 Modbus protocol description

4.3 Timing of the communication

Character
transmission
time
Example
Timing scheme
16
Start and end of a data block are marked by transmission pauses. The
character transmission time (time required to transmit one single character)
depends on the baud rate and the data format used.
For a data format of 8 data bits, no parity bit and one stop bit, this is:
Character transmission time [ms] = 1000 * 9 bit ÷ baud rate
For the other data formats, this is:
Character transmission time [ms] = 1000 * 10 bit ÷ baud rate
Baud rate [baud]
38400
19200
9600
A data request runs according to the following timing scheme:
Data request
Master
Slave
t Internal waiting time of the paperless recorder prior to checking
1
the data request and the internal processing time.
min.:
typical:
max.:
Data format [bit]
10
9
10
9
10
9
Response
t
1
5 ms
5 ... 45 ms
60 ms or set "minimum response time"
character transmission
time [ms]
0,260
0,234
0,521
0,469
1,042
0,938
Data request
t
2
t