Nexcom Peak 602VL, Руководство пользователя

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Peak 602VL User's Guide Rev. B0 Dec. 2000
Apendix
Watch Dog Timer Programming Procedure
••••
Power on or reset the system
The initial value of WDT Control Register (D4~D0) is zero, when power is on or reset the system. The
following means the initial value of WDT ( 00000000b ) :
Bit Value Mean
4 0 Select Reset
3 0 Disable Watch Dog Timer
2, 1, 0 0 0 0 Select 64 second
••••
Initialize the SQW of RTC (set SQW output period=0.5 second)
To initialize the SQW of RTC Component is to set the SQW signal which is output period=0.5 second.
It offers the basic frequency of the WDT counter.
The following is an example of initializing the SQW signal program in Intel 8086 assembly language.
; (Generate SQW = 0.5 Sec.)
; (Generate SQW = 0.5 Sec.) ; (Generate SQW = 0.5 Sec.)
; (Generate SQW = 0.5 Sec.)
Mov Mov Mov Mov dx, 70h dx, 70h dx, 70h dx, 70h
Mov Mov Mov Mov ax, 0Ah ax, 0Ah ax, 0Ah ax, 0Ah
Out Out Out Out dx, al dx, al dx, al dx, al ; Out port 70h = 0Ah ; Out port 70h = 0Ah ; Out port 70h = 0Ah ; Out port 70h = 0Ah
Mov Mov Mov Mov dx, 71h dx, 71h dx, 71h dx, 71h
Mov
Mov Mov
Mov ax, 2Fh
ax, 2Fh ax, 2Fh
ax, 2Fh
Out
Out Out
Out dx, al
dx, al dx, al
dx, al ; Out port 71h = 2Fh
; Out port 71h = 2Fh ; Out port 71h = 2Fh
; Out port 71h = 2Fh
; (enable the SQW output) ; (enable the SQW output) ; (enable the SQW output) ; (enable the SQW output)
Mov Mov Mov Mov dx, 70h dx, 70h dx, 70h dx, 70h
Mov Mov Mov Mov ax, 0Bh ax, 0Bh ax, 0Bh ax, 0Bh
Out
Out Out
Out dx, al
dx, al dx, al
dx, al ; Out port
; Out port ; Out port
; Out port 70h = 0Bh
70h = 0Bh 70h = 0Bh
70h = 0Bh
Mov
Mov Mov
Mov dx, 71h
dx, 71h dx, 71h
dx, 71h
Mov Mov Mov Mov ax, 0Ah ax, 0Ah ax, 0Ah ax, 0Ah
Out Out Out Out dx, al dx, al dx, al dx, al ; Out port 71h = 0Ah ; Out port 71h = 0Ah ; Out port 71h = 0Ah ; Out port 71h = 0Ah