It is in the on-line help in TRiLOGI Version 5.0. Press F1 when in TRiLOGI and select the "TBASIC Keyword Reference" link. I have reproduce it as follow:
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STATUS (n)
Purpose Return the status of various system operations. Function Returned value
status (1) 0 - Normal power on reset
1 - Reset by Watch Dog Timer (WDT)
status (2) 0 - READMODBUS or WRITEMODBUS failure
1 - READMODBUS or WRITEMODBUS successful
status(
PLC?s ID address stored in EEPROM for host communication
Examples IF STATUS(2) 'MODBUS READ/WRITE OK
?
ELSE 'MODBUS READ/WRITE failed
?
ENDIF