Toshiba T2N - Manual (Page 112)

2.INTERNAL OPERATIONS
User’s manual 99
The system initialization is performed after power ON. That is, Hardware
diagnostics and initialization followed by system initialization as follows.
The sequence of process is shown below.
CPU hardware diagnostics and initialization
The system ROM check, the system RAM check and initial set up, the
peripheral LSI check and initial set up, the calendar LSI and the language
processor (LP) check take place.
Power OFF time, Power ON time registration
The last time the power was switched OFF is registered in the event history
table, and the present date and time of Power ON read from the calendar
LSI is recorded. Also, the special register (SW0007-SW013) are set into
the present date and time.
Battery cheak
The battery voltage is checked for the user program and the user data back
up. If the battery voltage is lower than the specified value a message is
recorded in the event hystory table ‘batt voltage drop’ together with the
special relay battery alarm flag (S000F) setting.
Initial load
The initial load means the term for the transfer of the contents of the user
program and the first 2K words of the data register (D0000-D2047), from
the peripheral memory (EEPROM) to the main memory (RAM), prior to
running the user program.
The initial load is performed or not, depending on the position of
operation mode switch and operation mode setting switches (DIP switches)
when the power is turned ON.
The performance table of initial load is shown below.
2.2
System Initialization
Battery check
Initial load
User data initialization
User program check
The system initialization from power
ON to completion :
approx. 2 seconds
(without initial load)
approx. 2-3 seconds
(with initial load)
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CPU hardware diagnostics and
initialization
Power OFF time,
Power ON time registration
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