15 lines
335 B
ArmAsm
15 lines
335 B
ArmAsm
;; File: pit.s
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;; Programmable Interval Timer (8253/8254)
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PIT_CHAN_0 equ 0x40
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PIT_CHAN_1 equ 0x41
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PIT_CHAN_2 equ 0x42
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PIT_CMD equ 0x43
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CMD_CHANNEL_1 equ (0x1 << 6)
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CMD_CHANNEL_2 equ (0x2 << 6)
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CMD_READ_BACK equ (0x3 << 6)
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CMD_ACCESS_LO equ (0x1 << 4)
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CMD_ACCESS_HI equ (0x2 << 4)
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CMD_ACCESS_LO_HI equ (0x3 << 4)
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