GTCO 2500 Series - Users Guide 2/3 - Manual (Page 17)

2500 Series 17
Switch 7: Spare
Switch 8 Spare
BANK 2: Model ID
BANK 3: Software ID
BANK 4: Analog to Digital Converter
BANK 5: Input
BANK 6: Grid Test
BANK 7: Checksum
BANK 8: Transducer Data
Test Descriptions
RUNTIME OR SELF-TESTS
RS-232 PINOUT
NON-VOLATILE MEMORY
CHECKSUM
ROM CHECKSUM
RAM READ/WRITE
This is NOT a failure indicator. Indicator lights #2 and #3
correspond to pins #2 and #3 of the RS-232 connector.
The indicator lights if -12 V is present on the pin.
All bytes of the non-volatile memory are added and
compared to a Checksum. If they are not equal, the test is
failed. Each time the memory is altered; a new Checksum
is calculated and stored.
The bytes of the ROM are exclusive-ORed. The test fails if
the ending value is non-zero.
The RAM is written with a checkerboard pattern, read and
compared with write data. The test fails if the two do not
match. Data needed by the system is moved so the entire
RAM may be checked without destroying its contents.