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Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: ivmarkov

openthread/src/esp.rs

@@ -63,6 +63,9 @@ impl<'a> EspRadio<'a> {
             pan_id: config.pan_id,
             short_addr: config.short_addr,
             ext_addr: config.ext_addr,
+            // The default of 10 is too small for OpenThread,
+            // which can have bursts of incoming frames, so we increase it to 50.
+            // TODO: See if we can get by with a smaller number to save memory.
             rx_queue_size: 50,
             ..Default::default()
         };
@@ -138,12 +141,17 @@ impl Radio for EspRadio<'_> {
                         ack_frame.channel
                     );
 
-                    let rssi = ack_frame.data[1..][ack_psdu_len] as i8;
+                    // Only read RSSI if there is at least one byte after the PSDU.
+                    let rssi = if ack_frame.data.len() > 1 + ack_psdu_len {
+                        Some(ack_frame.data[1 + ack_psdu_len] as i8)
+                    } else {
+                        None
+                    };
 
                     return Ok(Some(PsduMeta {
                         len: ack_psdu_len,
                         channel: ack_frame.channel,
-                        rssi: Some(rssi),
+                        rssi,
                     }));
                 }
             }
@@ -152,7 +160,7 @@ impl Radio for EspRadio<'_> {
         } else {
             trace!("ESP Radio, transmission failed");
 
-            // Report as NoAck error so OpenThread SubMac retries
+            // Report as a failure so OpenThread SubMac retries
             Err(RadioErrorKind::TxFailed)
         }
     }

openthread/src/radio.rs

@@ -168,10 +168,13 @@ impl Config {
     pub const fn new() -> Self {
         Self {
             channel: 11,
+            // Run with max power by default
+            // TODO: Figure out how to have this specified by the user
             power: 20,
             cca: Cca::Carrier,
             sfd: 0,
             promiscuous: false,
+            // OpenThread can have bursts of incoming frames, so we need to receive during idle state to not miss them.
             rx_when_idle: true,
             pan_id: None,
             short_addr: None,