39 lines
1,002 B
PHP
39 lines
1,002 B
PHP
;++
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;
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; Copyright (c) 1996-97 Microsoft Corporation
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;
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; Module Name:
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;
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; mp8254.inc
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;
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; Abstract:
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;
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; This module contains common definitions for the 8254 used
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; by the timer tick routine and the query peformance counter
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; routine.
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;
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; Author:
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;
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; Shivnandan Kaushik
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;
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;--
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;
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; Constants used to initialize timer 0
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;
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TIMER1_DATA_PORT0 EQU 40H ; Timer1, channel 0 data port
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TIMER1_CONTROL_PORT0 EQU 43H ; Timer1, channel 0 control port
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COMMAND_8254_COUNTER0 EQU 00H ; Select count 0
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COMMAND_8254_RW_16BIT EQU 30H ; Read/Write LSB first then MSB
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COMMAND_8254_MODE2 EQU 4 ; Use mode 2
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COMMAND_8254_BCD EQU 0 ; Binary count down
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COMMAND_8254_LATCH_READ EQU 0 ; Latch read command
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PERFORMANCE_FREQUENCY EQU 1193182 ; frequency of 8254
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PERFORMANCE_INTERVAL EQU 0ffffH ; Maximum counter value
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PERF_USE_8254 EQU 01h
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PERF_8254_INITIALIZED EQU 40h
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