From 08d5a813830f1a3e66f8394da82c4f64bff4a72a Mon Sep 17 00:00:00 2001
From: windowsair <msdn_02@sina.com>
Date: Tue, 18 Jan 2022 22:12:41 +0800
Subject: [PATCH] feat(uart): Change baudrate by first ime recv content

---
 README.md          | 25 +++++++++++++++++++++----
 main/uart_bridge.c | 14 ++++++++++++++
 2 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index 627caf4..25d8522 100644
--- a/README.md
+++ b/README.md
@@ -66,8 +66,6 @@ There is built-in ipv4 only mDNS server. You can access the device using `dap.lo
 |----------------|--------|
 | SWCLK          | GPIO14 |
 | SWDIO          | GPIO13 |
-| LED\_CONNECTED | GPIO2  |
-| LED\_RUNNING   | GPIO15 |
 | TVCC           | 3V3    |
 | GND            | GND    |
 
@@ -83,11 +81,18 @@ There is built-in ipv4 only mDNS server. You can access the device using `dap.lo
 | TDO                | GPIO16  |
 | nTRST \(optional\) | GPIO0\* |
 | nRESET             | GPIO5   |
-| LED\_CONNECTED     | GPIO2   |
-| LED\_RUNNING       | GPIO15  |
 | TVCC               | 3V3     |
 | GND                | GND     |
 
+--------------
+
+| Other              |               |
+|--------------------|---------------|
+| LED\_WIFI_STATUS   | GPIO15        |
+| Tx                 | GPIO2         |
+| Rx                 | GPIO3 (U0RXD) |
+
+> Rx and Tx is used for uart bridge, not enabled by default.
 
 ----
 
@@ -252,6 +257,18 @@ The flash size of the board can be checked with the esptool.py tool:
 esptool.py -p (PORT) flash_id
 ```
 
+### Uart TCP Bridge
+
+This feature provides a bridge between TCP and Uart:
+```
+Send data   ->  TCP  ->  Uart TX -> external devices
+
+Recv data   <-  TCP  <-  Uart Rx <- external devices
+```
+
+For performance reasons, this feature is not enabled by default. You can can modify [wifi_configuration.h](main/wifi_configuration.h) to turn it on.
+
+
 ----
 
 ## Develop
diff --git a/main/uart_bridge.c b/main/uart_bridge.c
index fa0e658..e41b3ab 100644
--- a/main/uart_bridge.c
+++ b/main/uart_bridge.c
@@ -74,6 +74,7 @@ static uint8_t uart_read_buffer[UART_BUF_SIZE];
 // use lwip buffer to write back
 static struct netconn *uart_netconn = NULL;
 static bool is_conn_valid = false; // lock free
+static bool is_first_time_recv = false;
 
 void uart_bridge_close() {
     netconn_events events;
@@ -215,6 +216,7 @@ void uart_bridge_task() {
 
             uart_netconn = nc_in;
             is_conn_valid = true;
+            is_first_time_recv = true;
         } else if (events.nc->state != NETCONN_LISTEN) {
             // if (events.nc && events.nc->pcb.tcp)
             //     tcp_nagle_disable(events.nc->pcb.tcp);
@@ -233,6 +235,18 @@ void uart_bridge_task() {
                 do {
                     netbuf_data(netbuf, (void *)&buffer, &len_buf);
                     // write to uart
+                    if (is_first_time_recv) { // change bard rate
+                        if (len_buf > 2 && buffer[len_buf - 2] == '\r' && buffer[len_buf - 1] == '\n') {
+                            buffer[len_buf - 2] = '\0';
+                            int baudrate = atoi(buffer);
+                            if (baudrate > 0 && baudrate < 2000000) {
+                                printf("change bard:%d\r\n", baudrate);
+                                uart_set_baudrate(UART_NUM_0, baudrate);
+                                uart_set_baudrate(UART_NUM_1, baudrate);
+                            }
+                        }
+                        is_first_time_recv = true;
+                    }
                     uart_write_bytes(UART_NUM_1, (const char *)buffer, len_buf);
                 } while (netbuf_next(netbuf) >= 0);
                 netbuf_delete(netbuf);