Tibor Nagy
36 lines
848 B
Rust
36 lines
848 B
Rust
use syscall::io::{Io, Pio};
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pub struct Pcspkr {
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command: Pio<u8>,
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channel: Pio<u8>,
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gate: Pio<u8>,
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}
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const PIT_FREQUENCY: usize = 0x1234DC;
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impl Pcspkr {
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pub fn new() -> Pcspkr {
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Pcspkr {
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command: Pio::new(0x43),
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channel: Pio::new(0x42),
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gate: Pio::new(0x61),
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}
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}
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pub fn set_frequency(&mut self, frequency: usize) {
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let div = PIT_FREQUENCY.checked_div(frequency).unwrap_or(0);
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self.command.write(0xB6);
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self.channel.write((div & 0xFF) as u8);
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self.channel.write(((div >> 8) & 0xFF) as u8);
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}
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pub fn set_gate(&mut self, state: bool) {
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let gate_value = self.gate.read();
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if state {
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self.gate.write(gate_value | 0x03);
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} else {
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self.gate.write(gate_value & 0xFC);
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}
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}
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}
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