NEXCOM NEX 732L2G - Manual (Page 65)

64 Appendix A NEX732L2G User Manual
Clear the WDT
The WDT counter internal cannot be longer than the preset time, otherwise, the WDT generates a NMI (Non
Maskable Interrupt) or sends a reset signal to the system.
Note: Before running WDT, clear the WDT to make sure the initial value is zero before enabling the WDT.
WDT Control Register (Write to WDT configuration port)
Note: This register writes to the WDT configuration port.
You can set the WDT Control Register to control the WDT working mode.
Follow below instructions to set the initial value of the WDT working mode.
1. Select the WDT time out occurs time
Time-out intervals decide by values of bit 2, bit 1, bit 0 in I/O port 2E0h
minute or second decide by values of bit 3 in I/O port 2E0h
2. Enable or Disable WDT Notice Output decide by bit 4 value in I/O port 2E0h
3. Enable or Disable NMI Output decide by bit 5 value in I/O port 2E0h
4. Enable or Disable Reset Output decide by bit 6 value in I/O port 2E0h
5. Enable or Disable the WDT decide by bit 7 value in I/O port 2E0h
After finishing the above settings, you must output the Control Register’s value to the WDT Configuration
Port. Then WDT will start according to the above settings.
Note: Build a mechanism in the program to continue to read the WDT Configuration Port for clearing
WDT before time out.