Improved NFC reading speed

src/drivers/nfc_pn532.rs

@@ -7,53 +7,9 @@ use pn532::i2c::I2CInterface;
 use pn532::requests::SAMMode;
 use pn532::{nb, Pn532, Request};
 
-/// Timer implementation required by `pn532::CountDown`.
-pub struct TimerWrapper {
-    start: Instant,
-    duration: Duration,
-    counter: u32,
-}
+pub type Pn532Device<I2C> = Pn532<I2CInterface<I2C>, (), 34>;
 
-impl TimerWrapper {
-    pub fn new() -> Self {
-        Self {
-            start: Instant::now(),
-            duration: Duration::ZERO,
-            counter: 0,
-        }
-    }
-}
-
-impl Default for TimerWrapper {
-    fn default() -> Self {
-        Self::new()
-    }
-}
-
-impl pn532::CountDown for TimerWrapper {
-    type Time = Duration;
-
-    fn start<T>(&mut self, timeout: T)
-    where
-        T: Into<Self::Time>,
-    {
-        self.start = Instant::now();
-        self.duration = timeout.into();
-        self.counter = 0;
-    }
-
-    fn wait(&mut self) -> nb::Result<(), Infallible> {
-        let elapsed = self.start.elapsed();
-        self.counter += 1;
-        if elapsed >= self.duration {
-            Ok(())
-        } else {
-            Err(nb::Error::WouldBlock)
-        }
-    }
-}
-
-pub type Pn532Device<I2C> = Pn532<I2CInterface<I2C>, (), 32>;
+pub const PAGES_PER_READ: usize = 4;
 
 /// PN532 NFC reader driver.
 pub struct NfcPn532Driver<I2C>
@@ -98,11 +54,12 @@ where
         }
     }
 
-    pub fn parse_nfc_page(iteration: u8, bytes: &[u8]) -> Result<[u8; 4], ()> {
+    pub fn parse_nfc_page(iteration: u8, bytes: &[u8]) -> Result<[u8; PAGES_PER_READ * 4], ()> {
         let success = bytes.first().is_some_and(|x| *x == 0);
         if success {
-            let mut arr = [0; 4];
-            arr.copy_from_slice(&bytes[1..5]);
+            let slice_len = bytes.len().min(PAGES_PER_READ * 4 + 1);
+            let mut arr = [0; PAGES_PER_READ * 4];
+            arr[..slice_len - 1].copy_from_slice(&bytes[1..slice_len]);
             Ok(arr)
         } else {
             info!("err  {iteration}: {:02x?}", bytes);
@@ -118,10 +75,10 @@ where
 
         let mut data: Vec<u8> = Vec::with_capacity(858);
 
-        for i in 0x0B..=230 {
+        for i in (0x0B..=230).step_by(PAGES_PER_READ) {
             let mut parse_result = Err(());
             while parse_result.is_err() {
-                let Ok(result) = self.pn532.process_async(&Request::ntag_read(i), 17).await else {
+                let Ok(result) = self.pn532.process_async(&Request::ntag_read(i), PAGES_PER_READ * 4 + 1).await else {
                     continue;
                 };
                 parse_result = Self::parse_nfc_page(i, result);
@@ -134,8 +91,6 @@ where
             };
             data.extend(bytes);
         }
-
-        info!("PN532 full card payload read over I2C: {:02x?}", data);
         Ok(data)
     }