Operating instructions

Detailed descriptions
16.4 I/O Address Areas
SIMATIC IPC427C
146 Operating Instructions, 10/2010, A5E02414743-03
Watchdog enable register / 066h select register (r/w address 062h)
1 1 1 960 ms / 64 s
Trigger red Watchdog LED
0 Red LED (WD) off
1 Red LED (WD) on
Watchdog error / Display and reset
0 WD inactive
1 WD triggered
Reset LED after watchdog alarm
(Bit 7 = write 1)
16.4.3 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).
16.4.4 CAN base address register (write only, address 066h)
A 512 byte window is created in the I/O area for the CAN controller (Philips SJA1000). The
block itself only needs 32 or 128 bytes of this depending on the operating mode. The
address window can be selected in 1024 byte steps between 4000h and 7C00h through the
CAN base address register (write only, address 066h).
A limited selection can be preset in the BIOS Setup.
Note
The CAN base address register shares its I/O address with other registers. The watchdog
enable register / 066h select register therefore must be selected before access.