Technical specifications
7.5 Hardware descriptions
SIMATIC IPC227G
Operating Instructions, 06/2021, A5E50059933-AA
81
7.5.5.4
Watchdog state register
Bit
Read/Write
state
Meaning of the bits
7
Read/Write
Not used for watchdog
6
Read/Write
Not used for watchdog
5
Write "1" Only Trigger Watchdog Timer I event. This bit is self-clearing.
4
Read/Write
Watchdog Timer I status bit:
•
0: Watchdog Timer I is running.
•
1: Watchdog Timer I issues time-out event.
3 to 0
Read/Write
Not used for watchdog
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
Bits
7
6
5
4
3
2
1
0
1
1
LED L1 Stop dark (default)
1
0
LED L1 lit red
0
1
LED L1 lit green
0
0
LED L1 lit orange
1
1
LED L2 Stop dark (default)
1
0
LED L2 lit red
0
1
LED L2 lit green
0
0
LED L2 lit orange
1
1
LED L3 Stop dark (default)
1
0
LED L3 lit red
0
1
LED L3 lit green
0
0
LED L3 lit orange
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.
