Jumpers to switch off the
coordination signals
All the output signals required for coordination (arbitration) can be
interrupted by removing a jumper plug. This is necessary to operate
the COR 923C as a PG multiplexer in the EU S5-185U.
Coordination Section
in operation
out of operation
All jumpers of EP 61 closed
All jumpers of EP 61 open
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.
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.
1
8
E P 6 1
9
1 6
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
7
4
3
2
1
0
Not assigned
6
923C Coordinator Module
System Manual
C79000-B8576-C199-03
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