Technical information
8.5 Hardware descriptions
SIMATIC IPC477D, IPC477D PRO
Operating Instructions, 11/2016, A5E31347228-AF
239
8.5.4.4
Battery status register (read-only, address 50Ch)
The status of the CMOS battery is monitored; the status (two-tier) can be read from the
battery status register.
Meaning of the bits
Battery status register (read-only, address 404Dh)
Bit
Meaning
7 6 5 4 3 2 1 0
0 0
CMOS battery capacity is still sufficient.
0 1
CMOS battery capacity is exhausted (remaining capacity is
sufficient for approx. one month)
1 1
CMOS battery is empty
8.5.4.5
NVRAM address register
NVRAM occupies a 512 KB memory address area that can be read via PCI registers.
Meaning of the bits
NVRAM address register
PCI register address:
NVRAM base address regis-
ter
PCI register content:
NVRAM memory address (default)
Length of the memory area
C2B0 0000
Address is assigned dynamically
(depending on device configura-
tion)
80000 h