Master Diagnostics
Diagnostic Inputs
The EL6731 features various diagnostic variables, which describe the state of the terminal and the Profibus and can be linked in the PLC:
Error
Shows the number of slaves with which data exchange could not take place in the last cycle. The box status (BoxState) of the slaves should only be checked if this value is not equal to 0.
ActualModulo
Indicates the current modulo. This variable is only of significance if the slaves are prioritized (see the Slave Prioritization/Multiple DP Cycles section)
DiagFlag
Indicates whether the card's master diagnostic information has changed. It can then be read via ADS by the controller program, after that the "DiagFlag" variable is reset.
Master Diagnostics Data
The master diagnostic data can be read by ADS:
|
ADS-Read parameters |
Meaning |
|---|---|
|
Net-ID |
Net-ID of the master (see the device's ADS tab) |
|
Port |
200 |
|
IndexGroup |
0x0000F100 |
|
IndexOffset |
offset within the diagnosis data |
|
Length |
Length of the diagnostic data that is to be read |
|
Data |
Diagnostic data |
The master diagnostic data has the following structure:
Offset | Description |
|---|---|
0 -125 | BusStatus List, one byte per station address 0-125 which contains the station status (see BoxState for PROFIBUS boxes and for non-selected stations: 0x80 - not present, 0x81 - slave, 0x82 - master not ready for token ring, 0x83 - master ready for token ring, 0x84 - master in token ring). |
126 - 127 | reserved |
128 - 135 | State of the EL6731 |
130 - 131 | detected bus errors |
136 - 137 | Send error counter for all sent telegrams. |
138 - 139 | Receive error counter for all received telegrams. |
140 - 255 | reserved for extensions |
256 - 257 | Sync Failed Counter (see MC-Diag tab) |
258 - 259 | Cycle Start Error Counter, counts up one when the PROFIBUS cycle is restarted before the old cycle is complete (intercepted by the TwinCAT-IO driver, only possible with customized drivers). |
260 - 261 | Time Control Failed Counter (see MC-Diag tab) |
262 - 263 | reserved for extensions |
264 - 265 | Minimum reload value of real time timer. |
266 - 267 | Maximum reload value of the real-time timer (max. jitter, see MC-Diag tab, = max. reload value - min. reload value) |
268 - 269 | PLL Overflow Counter (see MC-Diag tab) |
270 - 271 | PLL Underflow Counter (see MC-Diag tab) |
296 - 297 | Output-Failed-Counter |
298 - 299 | Input-Failed-Counter |
300 - 301 | actual Cycle-Time (µs) |
302 – 303 | min. Cycle-Time (µs) |
304 - 305 | max. Cycle-Time (µs) |
306 - 307 | CycleWithNoDxch-Counter |
308 - 309 | CycleWithRepeat-Counter |
310- 311 | max. Repeat/Cycle |
 | Further information on the diagnostic data Further information on the diagnostic data can be found in the chapter DP-Diag tab. |