Table B.1: Watchdog Timer Registers
Address of | Attribute | Description |
register (2E) |
|
|
|
|
|
Read/Write | Value (2F) |
|
| and |
|
| description |
|
|
|
|
87 (hex) | Write this address to I/O address | |
|
| port 2E (hex) twice to unlock the |
|
| W83627HF |
|
|
|
07 (hex) | write | Write 08 (hex) to select register of |
|
| watchdog timer. |
|
|
|
30 (hex) | write | Write 01 (hex) to enable the function |
|
| of the watchdog timer. Disabled is |
|
| set as default. |
|
|
|
F5 (hex) | write | Set seconds or minutes as units for |
|
| the timer. |
|
|
|
Write 0 to bit 3: set second as counting unit. [default]
Write 1 to bit 3: set minute as counting unit
F6 (hex) | write | 0: stop timer [default]01~FF (hex): |
|
| The amount of the count, in seconds |
|
| or minutes, depends on the value |
|
| set in register F5 (hex). This number |
|
| decides how long the watchdog |
|
| timer waits for strobe before gener- |
|
| ating an interrupt or reset signal. |
|
| Writing a new value to this register |
|
| can reset the timer to count with the |
|
| new value. |
|
|
|
F7 (hex) | rd/wr | Bit 6: Write 1 to enable keyboard to |
|
| reset the timer, 0 to disable.[default] |
|
| Bit 5: Write 1 to generate a timeout |
|
| signal immediately and automati- |
|
| cally return to 0. [default=0] Bit 4: |
|
| Read status of watchdog timer, 1 |
|
| means timer is "time out". |
|
|
|
AA (hex) | Write this address to I/O port 2E | |
|
| (hex) to lock the watchdog timer.2 |
|
|
|
40 |
