Siemens SIMATIC NET CP 142-2, Manual, Page: 32 / 84

B8976111/02 AS-i Master Module CP 142-2
3-10
3.3.2 Diagnostics and Reaction to Interrupts with the BM147
3.3.2.1 Overview
If the CP 142-2 detects an error during operation (AS-i slave failed, EEPROM fault on the CP, ...), it
indicates this by triggering a diagnostic interrupt.
The BM147 then interrupts the cyclic user program (OB1) enters the event as “module fault” in the
system diagnostic buffer and then behaves as follows:
± ±
If the user has not programmed the corresponding interrupt OB (OB82), the BM147
changes to STOP.
±
If the user has programmed OB82, this is started by the PLC operating system. The local data
of OB82 provide the user with certain diagnostic information (which module triggered the
interrupt and what type of error occurred ...). More detailed diagnostic information (which slave
has failed ...) is available to the application program if it reads diagnostic data record DS 1 using
the system function SFC59 (“RD_REC”). Once OB82 has been executed, the BM147 continues
the cyclic program (OB1) starting at the point at which it was interrupted.
3.3.2.2 Interrupt Events
The CP 142-2 distinguishes between interrupt events entering and leaving the state. If the occurrence
of an interrupt event leads to an error-free state (AS-i-CONFIG_OK=TRUE no internal CP error), a
diagnostic interrupt leaving the state is triggered (in OB82: Bit OB82_MDL_DEFECT = 0). All other
interrupt events result in a diagnostic interrupt entering the state (Bit OB82_MDL_DEFECT = 1).
The following events can lead to a diagnostic interrupt being triggered by the CP 142-2:
±
All changes to the AS-i slave configuration in the protected mode
±
AS-i Power Fail in the protected mode
±
EEPROM error