Bently Nevada 3300/01 Series, Руководство по эксплуатации

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System Monitor
80175-01
17 SELF TEST
The Serial Interface performs the following internal self tests on power-up:
Rom Check A checksum calculation is performed on the rom memory. The value obtained is
compared with a previously calculated value stored in memory. If the values do not
compare, an error flag is set and bit 0 of the Diagnostic Register is set.
Ram Check A n alternating ones and zeros ram test is done on all but the upper 30 bytes of ram
(482 bytes). Also a test is conducted to verify that the COP ON bit is set in the
68HC11 processor. If a ram failure occurs, bit 1 of the Diagnostic Register is set.
I/O Port Test This test checks a portion of the mux control comparator hardware on the interface
circuit board. If a failure occurs, bit 5 of the Diagnostic Register is set.
SPI Test A loop through check of the switch registers on the interface circuit board is
performed using the serial peripheral interface of the 68HC11 processor. If an error
occurs, bit 6 of the Diagnostic Register is set.
If any error occurs during the Power-up self test, the red OK led on the Serial Interface circuit board
will be turned off. The interface program will be allowed to continue. Reliable operation of the
interface will be questionable if the OK led is off.
If the Power-up self tests pass, the red OK led will be permanently turned on.
The Serial Interface OK led is controlled only at power-up. No on-line tests are performed.
If the SERV switch is set ON at power-up, the same self tests are performed but the interface will not
be allowed to continue operation after completion of the tests. If a self test fails the OK led will be
turned off. If the self tests all pass, the OK led will be flashed at a constant rate.
The Diagnostic Register can be returned with a Modbus message using function code 8 and
diagnostic code 2 (loopback maintenance message).
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