Adding support for DBM
-use super::{hal, timers, DmaConfig, PeripheralToMemory, Transfer};
-
-const INPUT_BUFFER_SIZE: usize = 1;
+use super::{SAMPLE_BUFFER_SIZE, hal, timers, DmaConfig, PeripheralToMemory, Transfer};
#[link_section = ".axisram.buffers"]
-static mut BUF: [[u16; INPUT_BUFFER_SIZE]; 2] = [[0; INPUT_BUFFER_SIZE]; 2];
+static mut BUF: [[u16; SAMPLE_BUFFER_SIZE]; 3] = [[0; SAMPLE_BUFFER_SIZE]; 3];
pub struct InputStamper {
_di0_trigger: hal::gpio::gpioa::PA3<hal::gpio::Alternate<hal::gpio::AF2>>,
- next_buffer: Option<&'static mut [u16; INPUT_BUFFER_SIZE]>,
+ next_buffer: Option<&'static mut [u16; SAMPLE_BUFFER_SIZE]>,
transfer: Transfer<
hal::dma::dma::Stream6<hal::stm32::DMA1>,
timers::tim5::Channel4InputCapture,
PeripheralToMemory,
- &'static mut [u16; INPUT_BUFFER_SIZE],
+ &'static mut [u16; SAMPLE_BUFFER_SIZE],
>,
}
@@ -32,21 +30,25 @@ impl InputStamper {
let dma_config = DmaConfig::default()
.transfer_complete_interrupt(true)
.memory_increment(true)
+ .circular_buffer(true)
+ .double_buffer(true)
.peripheral_increment(false);
+ // This needs to operate in double-buffer+circular mode so that we don't potentially drop
+ // input timestamps.
let mut timestamp_transfer: Transfer<_, _, PeripheralToMemory, _> =
Transfer::init(
stream,
input_capture,
unsafe { &mut BUF[0] },
- None,
+ unsafe { Some(&mut BUF[1]) },
dma_config,
);
timestamp_transfer.start(|_| {});
Self {
- next_buffer: unsafe { Some(&mut BUF[1]) },
+ next_buffer: unsafe { Some(&mut BUF[2]) },
transfer: timestamp_transfer,
_di0_trigger: trigger,
}
