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Diffstat (limited to 'kernel/old/include/x86/pit.h')
| -rw-r--r-- | kernel/old/include/x86/pit.h | 82 |
1 files changed, 0 insertions, 82 deletions
diff --git a/kernel/old/include/x86/pit.h b/kernel/old/include/x86/pit.h deleted file mode 100644 index 269fcec..0000000 --- a/kernel/old/include/x86/pit.h +++ /dev/null @@ -1,82 +0,0 @@ -/* -** @file pit.h -** -** @author Warren R. Carithers -** @author K. Reek -** -** Definitions of constants and macros for the -** Intel 8254 Programmable Interval Timer -** -*/ - -#ifndef X86PIT_H_ -#define X86PIT_H_ - - -/* -** Hardware timer (Intel 8254 Programmable Interval Timer) -** -** Control word layout: -** -** Bit 7 6 | 5 4 | 3 2 1 | 0 -** Field SC1 SC0|RW1 RW0|M2 M1 M0 |BCD -** -** SC - select counter -** RW - read/write -** M - mode -** BCD - binary or BCD counter -*/ - -/* Frequency settings */ -#define PIT_DEFAULT_TICKS_PER_SECOND 18 // actually 18.2065Hz -#define PIT_DEFAULT_MS_PER_TICK (1000/PIT_DEFAULT_TICKS_PER_SECOND) -#define PIT_FREQ 1193182 // clock cycles/sec - -/* Port assignments */ -#define PIT_BASE_PORT 0x40 // I/O port for the timer -# define PIT_0_PORT (PIT_BASE_PORT) -# define PIT_1_PORT (PIT_BASE_PORT+1) -# define PIT_2_PORT (PIT_BASE_PORT+2) -# define PIT_CONTROL_PORT (PIT_BASE_PORT+3) - -/* BCD field */ -#define PIT_USE_DECIMAL 0x00 // 16-bit binary counter (default) -#define PIT_USE_BCD 0x01 // BCD counter - -/* Timer modes */ -#define PIT_MODE_0 0x00 // int on terminal count -#define PIT_MODE_1 0x02 // one-shot -#define PIT_MODE_2 0x04 // divide-by-N -#define PIT_MODE_3 0x06 // square-wave -#define PIT_MODE_4 0x08 // software strobe -#define PIT_MODE_5 0x0a // hardware strobe - -/* Timer 0 settings */ -#define PIT_0_SELECT 0x00 // select timer 0 -#define PIT_0_LOAD 0x30 // load LSB, then MSB -#define PIT_0_NDIV PIT_MODE_2 // divide-by-N counter -#define PIT_0_SQUARE PIT_MODE_3 // square-wave mode -#define PIT_0_ENDSIGNAL 0x00 // assert OUT at end of count - -/* Timer 1 settings */ -#define PIT_1_SELECT 0x40 // select timer 1 -#define PIT_1_READ 0x30 // read/load LSB then MSB -#define PIT_1_RATE 0x06 // square-wave, for USART - -/* Timer 2 settings */ -#define PIT_2_SELECT 0x80 // select timer 1 -#define PIT_2_READ 0x30 // read/load LSB then MSB -#define PIT_2_RATE 0x06 // square-wave, for USART - -/* Timer read-back */ -#define PIT_READBACK 0xc0 // perform a read-back -#define PIT_RB_NOT_COUNT 0x20 // don't latch the count -#define PIT_RB_NOT_STATUS 0x10 // don't latch the status -#define PIT_RB_CHAN_2 0x08 // read back channel 2 -#define PIT_RB_CHAN_1 0x04 // read back channel 1 -#define PIT_RB_CHAN_0 0x02 // read back channel 0 -#define PIT_RB_ACCESS_MASK 0x30 // access mode field -#define PIT_RB_OP_MASK 0x0e // oper mode field -#define PIT_RB_BCD_MASK 0x01 // BCD mode field - -#endif |