serial: resync serial data after invalid read

User reported bm1397 received an invalid packet and was unable to continue without manually reset the device. This patch enables the serial comms to resync when invalid/short data is received issue skot#24
tommywatson · Oct 20, 2023 · e2bb38f · e2bb38f
1 parent a4da6e2
commit e2bb38f
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Showing 4 changed files with 44 additions and 42 deletions.
diff --git a/components/bm1397/bm1366.c b/components/bm1397/bm1366.c
@@ -633,24 +633,7 @@ void BM1366_send_work(void * pvParameters, bm_job * next_bm_job)
 
 asic_result * BM1366_receive_work(void)
 {
-    // wait for a response, wait time is pretty arbitrary
-    int received = SERIAL_rx(asic_response_buffer, 11, 60000);
-
-    if (received < 0) {
-        ESP_LOGI(TAG, "Error in serial RX");
-        return NULL;
-    } else if (received == 0) {
-        // Didn't find a solution, restart and try again
-        return NULL;
-    }
-
-    if (received != 11 || asic_response_buffer[0] != 0xAA || asic_response_buffer[1] != 0x55) {
-        ESP_LOGI(TAG, "Serial RX invalid %i", received);
-        ESP_LOG_BUFFER_HEX(TAG, asic_response_buffer, received);
-        return NULL;
-    }
-
-    return (asic_result *) asic_response_buffer;
+    return SERIAL_rx_aa55(asic_response_buffer,11);
 }
 
 uint16_t reverse_uint16(uint16_t num)

diff --git a/components/bm1397/bm1397.c b/components/bm1397/bm1397.c
@@ -378,29 +378,7 @@ void BM1397_send_work(void *pvParameters, bm_job *next_bm_job)
 
 asic_result *BM1397_receive_work(void)
 {
-
-    // wait for a response, wait time is pretty arbitrary
-    int received = SERIAL_rx(asic_response_buffer, 9, 60000);
-
-    if (received < 0)
-    {
-        ESP_LOGI(TAG, "Error in serial RX");
-        return NULL;
-    }
-    else if (received == 0)
-    {
-        // Didn't find a solution, restart and try again
-        return NULL;
-    }
-
-    if (received != 9 || asic_response_buffer[0] != 0xAA || asic_response_buffer[1] != 0x55)
-    {
-        ESP_LOGI(TAG, "Serial RX invalid %i", received);
-        ESP_LOG_BUFFER_HEX(TAG, asic_response_buffer, received);
-        return NULL;
-    }
-
-    return (asic_result *)asic_response_buffer;
+    return SERIAL_rx_aa55(asic_response_buffer,9);
 }
 
 task_result *BM1397_proccess_work(void *pvParameters)

diff --git a/components/bm1397/include/serial.h b/components/bm1397/include/serial.h
@@ -10,4 +10,7 @@ int16_t SERIAL_rx(uint8_t *, uint16_t, uint16_t);
 void SERIAL_clear_buffer(void);
 void SERIAL_set_baud(int baud);
 
-#endif /* SERIAL_H_ */
+// recieve packet with 0xaa 0x55 header
+void *SERIAL_rx_aa55(uint8_t *data,const int length);
+
+#endif /* SERIAL_H_ */
diff --git a/components/bm1397/serial.c b/components/bm1397/serial.c
@@ -94,3 +94,41 @@ void SERIAL_clear_buffer(void)
 {
     uart_flush(UART_NUM_1);
 }
+
+/**
+ * @brief recieve packet with 0xaa 0x55 header
+ * @param data - buffer for received serial data
+ * @param length - length of expected packet
+ */
+void *SERIAL_rx_aa55(uint8_t *data,const int length) {
+    for(int len=0; len < length;) {
+        // wait for a response, wait time is pretty arbitrary
+        int received = SERIAL_rx(data+len, length-len, 60000);
+        if (received < 0) {
+            ESP_LOGI(TAG, "Error in serial RX");
+            return NULL;
+        } else if (received == 0) {
+            // Didn't find a solution, restart and try again
+            return NULL;
+        }
+
+        if (len+received > 2) {
+            // valid start
+            if (data[0] == 0xAA && data[1] == 0x55) {
+                len += received;
+            } else {
+                for(int count = 1; count < len + received; ++count) {
+                    if(*(data+count) == 0xAA) {
+                        // move to head and adjust read length
+                        memmove(data, data+count, len+received-count);
+                        len+=received-count;
+                        break;
+                    }
+                }
+            }
+        } else {
+            len+=received;
+        }
+    }
+    return data;
+}