diff options
| author | Curly <[email protected]> | 2025-02-23 07:33:58 -0800 |
|---|---|---|
| committer | Curly <[email protected]> | 2025-02-23 07:33:58 -0800 |
| commit | 3932835998802fc3abf7cce4f736e072858ebfd1 (patch) | |
| tree | 5dd714b99bc74a03556c58809237c88691c293bb /examples/rp235x/src/bin/pio_rotary_encoder_rxf.rs | |
| parent | c3c67db93e627a4fafe5e1a1123e5cbb4abafe47 (diff) | |
rename `rp23` (?) folder to `rp235x`; fix `ci.sh` to use `rp235x` folder
Diffstat (limited to 'examples/rp235x/src/bin/pio_rotary_encoder_rxf.rs')
| -rw-r--r-- | examples/rp235x/src/bin/pio_rotary_encoder_rxf.rs | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/examples/rp235x/src/bin/pio_rotary_encoder_rxf.rs b/examples/rp235x/src/bin/pio_rotary_encoder_rxf.rs new file mode 100644 index 000000000..0216c131b --- /dev/null +++ b/examples/rp235x/src/bin/pio_rotary_encoder_rxf.rs | |||
| @@ -0,0 +1,112 @@ | |||
| 1 | //! This example shows how to use the PIO module in the RP235x to read a quadrature rotary encoder. | ||
| 2 | //! It differs from the other example in that it uses the RX FIFO as a status register | ||
| 3 | |||
| 4 | #![no_std] | ||
| 5 | #![no_main] | ||
| 6 | |||
| 7 | use defmt::info; | ||
| 8 | use embassy_executor::Spawner; | ||
| 9 | use embassy_rp::gpio::Pull; | ||
| 10 | use embassy_rp::peripherals::PIO0; | ||
| 11 | use embassy_rp::pio::program::pio_asm; | ||
| 12 | use embassy_rp::{bind_interrupts, pio}; | ||
| 13 | use embassy_time::Timer; | ||
| 14 | use fixed::traits::ToFixed; | ||
| 15 | use pio::{Common, Config, FifoJoin, Instance, InterruptHandler, Pio, PioPin, ShiftDirection, StateMachine}; | ||
| 16 | use {defmt_rtt as _, panic_probe as _}; | ||
| 17 | |||
| 18 | // Program metadata for `picotool info` | ||
| 19 | #[link_section = ".bi_entries"] | ||
| 20 | #[used] | ||
| 21 | pub static PICOTOOL_ENTRIES: [embassy_rp::binary_info::EntryAddr; 4] = [ | ||
| 22 | embassy_rp::binary_info::rp_program_name!(c"example_pio_rotary_encoder_rxf"), | ||
| 23 | embassy_rp::binary_info::rp_cargo_version!(), | ||
| 24 | embassy_rp::binary_info::rp_program_description!(c"Rotary encoder (RXF)"), | ||
| 25 | embassy_rp::binary_info::rp_program_build_attribute!(), | ||
| 26 | ]; | ||
| 27 | |||
| 28 | bind_interrupts!(struct Irqs { | ||
| 29 | PIO0_IRQ_0 => InterruptHandler<PIO0>; | ||
| 30 | }); | ||
| 31 | |||
| 32 | pub struct PioEncoder<'d, T: Instance, const SM: usize> { | ||
| 33 | sm: StateMachine<'d, T, SM>, | ||
| 34 | } | ||
| 35 | |||
| 36 | impl<'d, T: Instance, const SM: usize> PioEncoder<'d, T, SM> { | ||
| 37 | pub fn new( | ||
| 38 | pio: &mut Common<'d, T>, | ||
| 39 | mut sm: StateMachine<'d, T, SM>, | ||
| 40 | pin_a: impl PioPin, | ||
| 41 | pin_b: impl PioPin, | ||
| 42 | ) -> Self { | ||
| 43 | let mut pin_a = pio.make_pio_pin(pin_a); | ||
| 44 | let mut pin_b = pio.make_pio_pin(pin_b); | ||
| 45 | pin_a.set_pull(Pull::Up); | ||
| 46 | pin_b.set_pull(Pull::Up); | ||
| 47 | |||
| 48 | sm.set_pin_dirs(pio::Direction::In, &[&pin_a, &pin_b]); | ||
| 49 | |||
| 50 | let prg = pio_asm!( | ||
| 51 | "start:" | ||
| 52 | // encoder count is stored in X | ||
| 53 | "mov isr, x" | ||
| 54 | // and then moved to the RX FIFO register | ||
| 55 | "mov rxfifo[0], isr" | ||
| 56 | |||
| 57 | // wait for encoder transition | ||
| 58 | "wait 1 pin 1" | ||
| 59 | "wait 0 pin 1" | ||
| 60 | |||
| 61 | "set y, 0" | ||
| 62 | "mov y, pins[1]" | ||
| 63 | |||
| 64 | // update X depending on pin 1 | ||
| 65 | "jmp !y decr" | ||
| 66 | |||
| 67 | // this is just a clever way of doing x++ | ||
| 68 | "mov x, ~x" | ||
| 69 | "jmp x--, incr" | ||
| 70 | "incr:" | ||
| 71 | "mov x, ~x" | ||
| 72 | "jmp start" | ||
| 73 | |||
| 74 | // and this is x-- | ||
| 75 | "decr:" | ||
| 76 | "jmp x--, start" | ||
| 77 | ); | ||
| 78 | |||
| 79 | let mut cfg = Config::default(); | ||
| 80 | cfg.set_in_pins(&[&pin_a, &pin_b]); | ||
| 81 | cfg.fifo_join = FifoJoin::RxAsStatus; | ||
| 82 | cfg.shift_in.direction = ShiftDirection::Left; | ||
| 83 | cfg.clock_divider = 10_000.to_fixed(); | ||
| 84 | cfg.use_program(&pio.load_program(&prg.program), &[]); | ||
| 85 | sm.set_config(&cfg); | ||
| 86 | |||
| 87 | sm.set_enable(true); | ||
| 88 | Self { sm } | ||
| 89 | } | ||
| 90 | |||
| 91 | pub async fn read(&mut self) -> u32 { | ||
| 92 | self.sm.get_rxf_entry(0) | ||
| 93 | } | ||
| 94 | } | ||
| 95 | |||
| 96 | pub enum Direction { | ||
| 97 | Clockwise, | ||
| 98 | CounterClockwise, | ||
| 99 | } | ||
| 100 | |||
| 101 | #[embassy_executor::main] | ||
| 102 | async fn main(_spawner: Spawner) { | ||
| 103 | let p = embassy_rp::init(Default::default()); | ||
| 104 | let Pio { mut common, sm0, .. } = Pio::new(p.PIO0, Irqs); | ||
| 105 | |||
| 106 | let mut encoder = PioEncoder::new(&mut common, sm0, p.PIN_4, p.PIN_5); | ||
| 107 | |||
| 108 | loop { | ||
| 109 | info!("Count: {}", encoder.read().await); | ||
| 110 | Timer::after_millis(1000).await; | ||
| 111 | } | ||
| 112 | } | ||
