Double-click on “Profibus_Master_x (Profibus_Master)” to open the “Profibus_Master” configuration in the editor window:
Click on “General” tab if not already opend.
Most of the parameters are calculated automatically. Uncheck [Use defaults] to enable values to be edited individually. Checking [Use defaults] again will revert all parameters to default values.
All times for the PROFIBUS parameters are given in bit time [tBit]. The bit time is the result of the reciprocal of the transmission rate:
tBit = 1 / transmission rate in [bit/s]
The conversion from milliseconds into a bit time is shown in following formula:
tBit = Time in [ms] * transmission rate in [bit/s]
The following parameters are available:
|
Parameter |
Default |
Value |
Description |
Parameter (Remark 1) |
|---|---|---|---|---|
|
Adresses |
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|
Station address |
1 |
0 ... 125 |
The individual device address of the master device on the bus. |
DpParameter -> Station address |
|
Highest station address |
126 |
0 ... 126 |
The highest bus address up to which a master searches for another master at the bus in order to pass on the token. This station address must on no account be smaller than the master station address. |
DpParameter -> Highest station address |
|
Mode |
||||
|
Auto-Clear mode |
Enabled |
Disabled |
The master operation mode will stay in the mode 'Operate' and the communication to all available slaves is kept up. |
AutoClearSupported |
|
Enabled |
The masters operation mode will change from 'Operate' to 'Clear' and it shuts down the communication to all assigned slaves, if at least 1 slave is not responding within the data control time. |
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|
Automatic startup |
Enable |
Disable |
Do not perform automatic startup |
AutoStart |
|
Enable |
Perform automatic startup |
|||
|
Parameters |
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|
Baud rate |
1500 |
9.6 19.2 45.45 93.75 187.5 500 1500 3000 6000 12000 |
Data transfer speed in [kBits/s]. The baud rate must be set to the same value for all devices on the bus. The result of changing the baud rate is that all other parameters must be recalculated. |
DpParameter -> Baudrate |
|
T_SL Slot time |
300 |
37 ... 65535 |
Monitoring time of the sender (requester) of a telegram for the acknowledgement of the recipient (responder). After expiration, a retry occurs in accordance with the value of maximum telegram retries. |
DpParameter -> TSL |
|
min. T_SDR Minimum station delay responder time |
11 |
1 ... 65535 |
Shortest time period that must elapsed before a remote recipient (responder) may send an acknowledgement of a received query telegram. The shortest time period between reception of the last bit of a telegram to the sending of the first bit of a following telegram. |
DpParameter -> min. TSDR |
|
max. T_SDR Maximum station delay responder time |
150 |
1 ... 65535 |
Longest time period that must elapse before a sender (requestor) may send a further query telegram. Greatest time period between reception of the last bit of a telegram to the sending of the first bit of a following telegram. The sender (requestor, master) must wait at least for this time period after the sending of an unacknowledged telegram (e.g. broadcast only) before a new telegram is sent. |
DpParameter -> max. TSDR |
|
T_QUI Quiet time |
0 |
0 ... 127 |
Time delay that occurs for modulators (modulator-trip time) and repeaters (repeater-switch time) for the change over from sending to receiving. |
DpParameter -> TQUI |
|
T_SET Setup time |
1 |
0 ... 255 |
Minimum period reaction time between the receipt of an acknowledgement to the sending of a new query telegram (reaction) by the sender (requestor). |
DpParameter -> TSET |
|
T_TR Target rotation time |
11894 |
1 ... 2 -1 (=16777215) |
Pre-set nominal token cycle time within the sender authorization (token). The available time for the master to send data telegrams to the slaves depends on the difference between the nominal and the actual token cycle time. The Target rotation time (TTR) is shown in Bit times [tBit] like the other bus parameters. Below the displayed bit time, the Target rotation time is also displayed in [ms]. The default value depends on the number of slaves attached to the master and their module configuration. |
DpParameter -> TTR |
|
Gap Gap update factor |
10 |
0 ... 255 |
Factor for determining after how many token cycles an added participant is accepted into the token ring. After expiry of the time period G*TTR, the station searches to see whether a further participant wishes to be accepted into the logical ring. |
DpParameter -> Gap update factor |
|
Retry limit Maximum retries |
1 |
1 ... 15 |
Maximum number of repeats in order to reach a station. |
DpParameter -> max. retry limit |
|
Data control time |
120 |
1 ... 224-1 |
Defines the time in [ms] within the Data_Transfer_List is updated at least once. After the expiration of this period, the master (class 1) reports its operating condition automatically via the Global_Control command. The default value depends on the transmission rate. |
DpParameter -> Data control time |
|
Slave interval Minimum slave interval |
2000 |
1 ... 65535 |
Defines the minimum time period between two slave list cycles in [µs]. The maximum value the active stations require is always given. The default value depends on the slave types. |
DpParameter -> min. slave interval |
|
Poll timeout Minimum poll timeout |
10 |
Sets the maximum period of time in [ms] during which the response has to be received. |
DpParameter -> Poll timeout |
|
Remark 1:
To display the parameters of this column, enable the option “Show generic device configuration views” under “Tools Options Device editor”.