From 76dc34b115f0644d8482456e55eda8e7e5310219 Mon Sep 17 00:00:00 2001
From: ede1998 <online@erik-hennig.me>
Date: Fri, 31 Jul 2026 23:20:55 +0200
Subject: [PATCH] retry on failure

---
 src/bin/main.rs | 30 ++++++++++++++++++++++--------
 1 file changed, 22 insertions(+), 8 deletions(-)

diff --git a/src/bin/main.rs b/src/bin/main.rs
index 4325f94..c1d509a 100644
--- a/src/bin/main.rs
+++ b/src/bin/main.rs
@@ -166,15 +166,16 @@ fn main() -> ! {
         ) {
             Ok(uid) => {
                 info!("uid = {uid:?}");
-                for i in (4..=231) {
-                    let result = pn532.process(&Request::ntag_read(i), 17, ms_1000).unwrap();
-                    let success = result.first().is_some_and(|x| *x == 0);
-                    if success {
-                        // info!("page {i}: {:02x?}", result);
-                        data.extend(&result[1..5]);
-                    } else {
-                        info!("err  {i}: {:02x?}", result);
+                for i in (0x0b..=230) {
+                    let mut parse_result = Err(());
+                    while parse_result.is_err() {
+                        let Ok(result) = pn532.process(&Request::ntag_read(i), 17, ms_1000) else {
+                            continue;
+                        };
+                        parse_result = parse_nfc(i, result);
                     }
+                    let bytes = parse_result.unwrap();
+                    data.extend(bytes);
                 }
                 info!("Full data: {data:02x?}");
                 data.clear();
@@ -191,6 +192,19 @@ fn main() -> ! {
     // for inspiration have a look at the examples at https://github.com/esp-rs/esp-hal/tree/esp-hal-v1.1.0/examples
 }
 
+fn parse_nfc(iteration: u8, bytes: &[u8]) -> Result<[u8; 4], ()> {
+    let success = bytes.first().is_some_and(|x| *x == 0);
+    if success {
+        // info!("page {i}: {:02x?}", result);
+        let mut arr = [0; 4];
+        arr.copy_from_slice(&bytes[1..5]);
+        Ok(arr)
+    } else {
+        info!("err  {iteration}: {:02x?}", bytes);
+        Err(())
+    }
+}
+
 struct TimerWrapper {
     // TODO Is that timer accurate enough?
     start: Instant,