Detail register descriptions – Lanner RS12-38800 User Manual

Page 63

第

第 56

56 頁

頁

頁: [1]

: [1]

: [1] 刪除

刪除

KevinYu

2005/6/22 3:21:00 PM

Detail Register Descriptions

A watchdog action consists of a series of watchdog instructions. A watchdog instruction is the

operation on a register region. This section describes the detail register in LPC I/O(W83627HF).

Watch Dog Timer Control Register

Watch Dog Timer is controlled by CRF5, CRF6, CRF7 of Logical Device.

CRF5 (PLED mode register. Default 0x00)

Bit 7-6 : select PLED mode

= 00 Power LED pin is tri-stated.

= 01 Power LED pin is drived low.

= 10 Power LED pin is a 1Hz toggle pulse with 50 duty cycle

= 11 Power LED pin is a 1/4Hz toggle pulse with 50 duty cycle.

Bit 5-4 : Reserved

Bit 3 : select WDTO count mode.

= 0 second

= 1 minute

Bit 2 : Enable the rising edge of keyboard Reset(P20) to force Time-out event.

= 0 Disable

= 1 Enable

Bit 1-0 : Reserved

CRF6 (Default 0x00)

Watch Dog Timer Time-out value. Writing a non-zero value to this register

causes the counter toload the value to Watch Dog Counter and start counting

down. If the Bit 7 and Bit 6 are set, anyMouse Interrupt or Keyboard Interrupt

event will also cause the reload of previously-loaded non-zerovalue to Watch

Dog Counter and start counting down. Reading this register returns current

value inWatch Dog Counter instead of Watch Dog Timer Time-out value.

Bit 7 - 0 = 0x00 Time-out Disable

= 0x01 Time-out occurs after 1 second/minute

= 0x02 Time-out occurs after 2 second/minutes

= 0x03 Time-out occurs after 3 second/minutes

= 0xFF Time-out occurs after 255 second/minutes