feat: adds the baud rate detection feature to ESP32-S3 and ESP32-C3

espressif · Feb 17, 2024 · c77ae60 · c77ae60
1 parent 668910a
commit c77ae60
Showing 1 changed file with 20 additions and 34 deletions.
diff --git a/cores/esp32/esp32-hal-uart.c b/cores/esp32/esp32-hal-uart.c
@@ -630,32 +630,32 @@ void log_print_buf(const uint8_t *b, size_t len){
 
 /*
  * if enough pulses are detected return the minimum high pulse duration + minimum low pulse duration divided by two. 
+ * In the case of S3 and C3 using XTAL as UART CLK SOURCE, one bit period = Negative Pulse Count + 1
  * This equals one bit period. If flag is true the function return inmediately, otherwise it waits for enough pulses.
  */
 unsigned long uartBaudrateDetect(uart_t *uart, bool flg)
 {
 // Baud rate detection only works for ESP32 and ESP32S2
-#if CONFIG_IDF_TARGET_ESP32 || CONFIG_IDF_TARGET_ESP32S2
     if(uart == NULL) {
         return 0;
     }
 
     uart_dev_t *hw = UART_LL_GET_HW(uart->num);
 
-    while(hw->rxd_cnt.edge_cnt < 30) { // UART_PULSE_NUM(uart_num)
+    while(uart_ll_get_rxd_edge_cnt(hw) < 30) { // UART_PULSE_NUM(uart_num)
         if(flg) return 0;
         ets_delay_us(1000);
     }
 
     UART_MUTEX_LOCK();
-    //log_i("lowpulse_min_cnt = %d hightpulse_min_cnt = %d", hw->lowpulse.min_cnt, hw->highpulse.min_cnt);
-    unsigned long ret = ((hw->lowpulse.min_cnt + hw->highpulse.min_cnt) >> 1);
+#if CONFIG_IDF_TARGET_ESP32 || CONFIG_IDF_TARGET_ESP32S2
+    unsigned long ret = ((uart_ll_get_low_pulse_cnt(hw) + uart_ll_get_high_pulse_cnt(hw)) >> 1);
+#else
+    unsigned long ret = uart_ll_get_neg_pulse_cnt(hw) + 1;
+#endif
     UART_MUTEX_UNLOCK();
 
     return ret;
-#else
-    return 0;
-#endif
 }
 
 
@@ -675,16 +675,12 @@ void uartStartDetectBaudrate(uart_t *uart) {
     uart_ll_set_autobaud_en(hw, true);
 }
 
-unsigned long
-uartDetectBaudrate(uart_t *uart)
+unsigned long uartDetectBaudrate(uart_t *uart)
 {
     if(uart == NULL) {
         return 0;
     }
 
-// Baud rate detection only works for ESP32 and ESP32S2
-#if CONFIG_IDF_TARGET_ESP32 || CONFIG_IDF_TARGET_ESP32S2
-
     static bool uartStateDetectingBaudrate = false;
 
     if(!uartStateDetectingBaudrate) {
@@ -698,37 +694,27 @@ uartDetectBaudrate(uart_t *uart)
     }
 
     uart_dev_t *hw = UART_LL_GET_HW(uart->num);
-    hw->auto_baud.en = 0;
+    uart_ll_set_autobaud_en(hw, false);
 
     uartStateDetectingBaudrate = false; // Initialize for the next round
-
-    unsigned long baudrate = getApbFrequency() / divisor;
 
-    //log_i("APB_FREQ = %d\nraw baudrate detected = %d", getApbFrequency(), baudrate);
-
-    static const unsigned long default_rates[] = {300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 74880, 115200, 230400, 256000, 460800, 921600, 1843200, 3686400};
-
+#if CONFIG_IDF_TARGET_ESP32 || CONFIG_IDF_TARGET_ESP32S2
+    unsigned long baudrate = getApbFrequency() / divisor;  // ESP32 and S2 APB Freq
+#else
+    unsigned long baudrate = (getXtalFrequencyMhz() * 1000000) / divisor;  // S3 and C3 XTAL Frequency
+#endif
+
+    static const unsigned long default_rates[] = {300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 74880, 115200, 230400, 250000, 
+                                                  256000, 460800, 500000, 921600, 1000000, 1843200, 2000000, 3686400};
     size_t i;
-    for (i = 1; i < sizeof(default_rates) / sizeof(default_rates[0]) - 1; i++)	// find the nearest real baudrate
-    {
-        if (baudrate <= default_rates[i])
-        {
-            if (baudrate - default_rates[i - 1] < default_rates[i] - baudrate) {
-                i--;
-            }
+    for (i = 1; i < sizeof(default_rates) / sizeof(default_rates[0]) - 1; i++)	{ // find the nearest real baudrate
+        if (baudrate <= default_rates[i]) {
+            if (baudrate - default_rates[i - 1] < default_rates[i] - baudrate) i--;
             break;
         }
     }
 
     return default_rates[i];
-#else
-#ifdef CONFIG_IDF_TARGET_ESP32C3 
-    log_e("ESP32-C3 baud rate detection is not supported.");
-#else
-    log_e("ESP32-S3 baud rate detection is not supported.");
-#endif
-    return 0;
-#endif
 }
 
 /*