variable length rx

src/lib.rs

@@ -81,10 +81,13 @@ where
         matches!(self.state, InternalState::Idle)
     }
 
-    pub fn start_rx(&mut self, rx_forever: bool) -> Result<(), Spi::Error> {
+    // Len is none when using a variable-length packet
+    pub fn start_rx(&mut self, len: Option<usize>, rx_forever: bool) -> Result<(), Spi::Error> {
         self.radio.clear_fifo()?;
         self.radio.clear_ph_and_modem_interrupts()?;
 
+        let len = len.unwrap_or(0);
+
         self.state = InternalState::Rx {
             data: [0; MAX_PACKET_LEN],
             i: 0,
@@ -96,8 +99,8 @@ where
             START_RX,
             self.channel,
             0,
-            (MAX_PACKET_LEN >> 8).try_into().unwrap(),
-            (MAX_PACKET_LEN & 0xff).try_into().unwrap(),
+            (len >> 8).try_into().unwrap(),
+            (len & 0xff).try_into().unwrap(),
             State::Rx.into(),
             if rx_forever {
                 State::Rx.into()