Technical specifications
7.5 Hardware descriptions
SIMATIC IPC227G
Operating Instructions, 07/2022, A5E50059933-AC
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7.5.5.4 Watchdog state register
Bit Read/Write
Meaning of the bits
Trigger Watchdog Timer I event. This bit is self-clearing.
Watchdog Timer I status bit:
• 0: Watchdog Timer I is running.
• 1: Watchdog Timer I issues time-out event.
7.5.5.5 Control register user LED L1/L2/L3
Meaning of the bits
The "PC ON/WD" LED flashes yellow to indicate the progress of the BIOS self-test during device
startup. After the BIOS self-test has been completed, the "PC ON/WD" LED lights up
continuously green.
Control register L1/L2/L3
LED L1 Stop dark (default)
LED L2 Stop dark (default)
LED L3 Stop dark (default)
7.5.5.6 Battery status register
The status of the CMOS battery is monitored; the status (two-tier) can be read from the
battery status register.