Application Examples
NON-MASKABLE INTERRUPT
SERVICE ROUTINE START
TRIGGER THE
WATCHDOG TIMER
IS IT SET?
YES
OTHER NMI SO CHECK
FOR SOURCES ELSE-
WHERE IN THE SYSTEM
AND HANDLE THEM
READ INTERRUPT RE-
QUEST REGISTER BIT 5
POWER FAIL NMI
SO DO THE FOLLOWING
SAVE REGISTERS, IE,
SEGMENT, AX, BX, CX,
DX, SI, DI, BP, SP, IN
BATTERY BACKED RAM
SAVE CRITICAL PRO-
GRAM DATA IN BATTERY
BACKED RAM
SET SYSTEM DATA
SAVED FLAG IN BATTERY
BACKED RAM, IE A
PATTERN LIKE AA556996h
NO
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