17 lines
498 B
C
17 lines
498 B
C
#pragma once
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// C.f https://wiki.osdev.org/PIT
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#define PIT_FREQ 1193182
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#define PIT_CHAN_0 0x40 // IRQ0
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#define PIT_CHAN_1 0x41 // Used for DRAM refresh. Not used anymore
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#define PIT_CHAN_2 0x42 // PC Speaker
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#define PIT_CMD 0x43
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// Cmd are
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// 7-6: select channel. 0 ->chan0, 1 -> chan1, 2 -> chan 2, 3 -> read back
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// 5-4: access mode. 0 -> latch count; 1 -> low value only; 2 -> high value only;
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// 3 -> low then high 3-1: mode. See https://wiki.osdev.org/PIT
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int initPit(unsigned int freq);
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