![background image](http://html1.mh-extra.com/html/ziatech-corporation/zt-8907/zt-8907_hardware-user-manual_3665381078.webp)
15. AC Power Fail
ÛZIATECH
77
In operation, a non-maskable interrupt is generated when AC power falls below
95 VRMS. The non-maskable interrupt must be enabled through jumper W6. The
application software must include a non-maskable interrupt service routine to perform
the following:
•
Determine if the AC power fail is the source of the interrupt request. The three
sources of non-maskable interrupts are:
–
AC power fail
–
STD bus NMIRQ*
–
PCI Parity Error
•
Preserve any critical information into the optional battery backed static RAM
(option T1) or flash memory. These data can then be retrieved at system restart with
appropriate user software.
•
Place the CPU in a dormant state using a halt instruction or a looping sequence that
is not reading or writing critical data to memory or I/O.