Technical information
8.5 Hardware descriptions
SIMATIC IPC477E
Operating Instructions, 11/2020, A5E37455003-AF
153
8.5.4.3
Watchdog trigger register (read only, address 066h)
Watchdog trigger register
The watchdog is triggered by a read action (address 066h) by this register. The result of the
read access can be disregarded (i.e., dummy read).
8.5.4.4
Output register user LED L1/L2/L3 (read/write, address 404Eh)
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.
Output register L1/L2/L3 (read/write, address 404Eh)
Bits
15
14
13
12-8 7
6
5
4-0
1
1
LED L1 / Run/Stop dark (default)
1
0
LED L1 / Run/Stop lit yellow
0
x
LED L1 / Run/Stop lit green
1
1
LED L2 / SF dark (default)
0
x
LED L2 / SF lit red
1
0
LED L2 / SF lit yellow
1
1
LED L3 / Maint dark (default)
0
x
LED L3 / Maint lit red
1
0
LED L3 / Maint lit yellow
xxxx
xx
xxxx
xx
Reserved (read/write)
