Siemens S5-135U/155U appendix Jumpers to, Switch off, Signals, Fault Register

Multiprocessor Operation/Coordinators

Jumpers to	All the output signals required for coordination (arbitration) can be
Switch off the	interrupted by removing a jumper plug. This is necessary to operate the COR
Coordination	923C as a PG multiplexer in the EU S5-185U.
Signals
	Coordination Section

in operation

out of operation

All jumpers of EP 61 closed

All jumpers of EP 61 open

	8	1
	EP 61
	9	16
	When the unit is delivered, all jumpers are closed.
Fault Register	The fault register is an 8-bit register and is readable by the CPU under
	address FEFFH. The register is written to by the bus monitor in the event of a
	bus error. Each CPU is assigned one bit of the fault register which is set to 1
	in the event of an error. The register is cleared each time the Stop signal
	becomes inactive.

74 3 2 1 0

Not assigned

Fault register FEFFH

Bit = 1: Bus error from CPU 1

Bit = 2: Bus error from CPU 2

Bit = 3: Bus error from CPU 3

Bit = 4: Bus error from CPU 4

The fault register can be read by all CPUs, allowing central functions to be initiated.

Note

The fault register and the page register are at address FEFFH (FFEFFH with the CPU 948). The page register is addressed by writing to FEFFH, and the fault register is addressed by reading out FEFFH.

System Manual	6-27
C79000-G8576-C199-06