MVI46-PDPS ♦ SLC Platform
Diagnostics and Troubleshooting
Profibus DP Slave Communication Module
User Manual
ProSoft Technology, Inc.
Page 33 of 53
Response Time Monitoring
The 'DP_Control' state serves response time monitoring of the DP master (Master_Add).
The set monitoring times results from multiplying both watchdog factors and multiplying
the result with the momentarily valid time base (1 ms or 10 ms):
TWD = (1 ms or 10 ms) * WD_Fact_1 * WD_Fact_2 (See byte 7 of the parameter
setting telegram)
The user can load the two watchdog factors (WD_Fact_1, and WD_Fact_2) and the time
base that represents a measurement for the monitoring
time via the ’Set_Param
telegram' with any value between 1 and 255.
EXCEPTION: The WD_Fact_1=WD_Fact_2=1 setting is not permissible. The circuit
does not check this setting.
Monitoring times between 2 ms and 650 s - independent of the baud rate - can be
implemented with the permissible watchdog factors. If the monitoring time runs out, the
SPC3 goes again to 'Baud_Control,' and the SPC3 generates the
'WD_DP_Control_Timeout-Interrupt'. In addition, the DP_State machine is reset, that is,
generates the reset states of the buffer management.
If another master accepts SPC3, then there is either a switch to 'Baud_Control" (WD_On
= 0), or there is a delay in 'DP_Control' (WD_On = 1), depending on the enabled
response time monitoring (WD_On = 0).
Status Register [1]
SPC3 ASIC slave status information provided to the master.
Bits
0 to 3
Baud rate:
The baud rates SPC3 found
0000 = 12 MBaud
0001 = 6 MBaud
0010 = 3 MBaud
0011 = 1.5 MBaud
0100 = 500 kBaud
0101 = 187.5 kBaud
0110 = 93.75 kBaud
0111 = 45.45 kBaud
1000 = 19.2 kBaud
1001 = 9.6 kBaud
Rest = Not possible
Bits
4 to 7
SPC3-Release:
Release no. for SPC3
0000 = Release 0
Rest = Not possible