Copyright © Vecow Co., Ltd. All Rights Reserved. SPC-2000 Series Ultra-compact Embedded System User
Manual
Appendix B:
WDT FUNCTION
A.
Function Description
The WDT are using internal Super IO function. However, you must entry super I/O configuration
mode to set it.
Super I/O special address port = 0x2E
Super I/O special data port
= 0x2F
GPIO Logical device is 0x07
B.
Entry Functions
1.
Entry MB PnP mode.
//write twice 0x87 value.
outportb(
Super I/O special address port
, 0x87);
outportb(
Super I/O special address port
, 0x01);
outportb(
Super I/O special address port
, 0x55);
outportb(
Super I/O special address port
, 0x55);
2.
Located on Logical Device 7(LOGIC_DEVICE_WDT)
//write 0x07 on Reg [0x07] , this setup must follow Step A. that can be workable.
outportb(
Super I/O special address port
, 0x07);
outportb(
Super I/O special data port
, 0x07);
3.
Config the WDT register
outb(WDT_Config,SPECIAL_ADDRESS_PORT);
outb(WDT_As_Second|WDT_Pin_PWRGD,SPECIAL_DATA_PORT);
4.
Start WDT Time out value
Here have 2 Byte for WDT timing count, MSB and LSB should be write the value separate.
outb(
WDT_TimeOut_LSB,SPECIAL_ADDRESS
_PORT);
outb(WDT_TimeOutValue,SPECIAL_DATA_PORT);
WDT_TimeOut_MSB,SPECIAL
WDT_TimeOut_LSB,SPECIAL