/* i8253.h - Intel 8253 PIT (Programmable Interrupt Timer) */ /* Copyright 1984-1993 Wind River Systems, Inc. */ /* modification history -------------------- 01b,16jun93,hdn updated to 5.1. 01a,20may92,hdn written. */ #ifndef __INCi8253h #define __INCi8253h #ifdef __cplusplus extern "C" { #endif /* * The macro PIT_REG_ADDR_INTERVAL must be defined * when including this header. */ /* default definitions */ #define CAST #define PIT_ADRS(base,reg) (CAST (base+(reg*PIT_REG_ADDR_INTERVAL))) /* register definitions */ #define PIT_CNT0(base) PIT_ADRS(base,0x00) /* Counter 0. */ #define PIT_CNT1(base) PIT_ADRS(base,0x01) /* Counter 1. */ #define PIT_CNT2(base) PIT_ADRS(base,0x02) /* Counter 2. */ #define PIT_CMD(base) PIT_ADRS(base,0x03) /* Control word. */ #ifdef __cplusplus } #endif #endif /* __INCi8253h */