Improve the connection of RTdunio PWM(stm32f401-st-nucleo) (#6192)

* Improve the connection of RTdunio PWM

* Update bsp/stm32/stm32f401-st-nucleo/applications/arduino_pinout/README.md

bsp/stm32/stm32f401-st-nucleo/applications/arduino_pinout/README.md

@@ -32,8 +32,8 @@ Hardware Drivers Config --->
 | 7 (D7)          | PA8           | 是     |                                                              |
 | 8 (D8)          | PA9           | 是     |                                                              |
 | 9 (D9)          | PC7           | 是     | PWM（定时器3发生）                                           |
-| 10 (D10)        | PB6           | 是     |  |
-| 11 (D11)        | PA7           | 是     |  |
+| 10 (D10)        | PB6           | 是     | PWM（定时器4发生） |
+| 11 (D11)        | PA7           | 是     | PWM（定时器1发生） |
 | 12 (D12)        | PA6           | 是     |  |
 | 13 (D13)        | PA5           | 是     | |
 | 14 (D14)        | PB9           | 是     | I2C1-SDA，被RT-Thread的I2C设备框架i2c1总线接管，不可当做普通IO |
@@ -53,6 +53,7 @@ Hardware Drivers Config --->
 > 1. 驱动舵机和analogWrite函数要选择不同定时器发生的PWM信号引脚，由于STM32的定时器4个通道需要保持相同的频率，如果采用相同的定时器发生的PWM分别驱动舵机和analogWrite，可能会导致舵机失效。
 > 2. USART2是Nucleo板的默认串口，理论应对接到了Arduino引脚编号的D0和D1，但是其实际用于串口通信，因此不允许当做普通IO来使用和操作。如果需要将D0、D1与STM32 USART2的引脚相连，需要手动焊接锡桥SB62、SB63。
 > 3. Nucleo板的Arduino接口中AVDD（即AREF）默认是与VDD相连的，如果需要扩展板提供外部参考电压，需要将SB57锡桥挑开。
+> 4. D11引脚是PWM反相位引脚(也就是常说的互补输出引脚CHxN)。但是这里不用考虑到占空比互补问题（CHx-20%，CHxN-80%），直接正常使用即可。
 
 > 参考资料
 >

bsp/stm32/stm32f401-st-nucleo/applications/arduino_pinout/pins_arduino.c

 /*
- * Copyright (c) 2006-2021, RT-Thread Development Team
+ * Copyright (c) 2006-2022, RT-Thread Development Team
  *
  * SPDX-License-Identifier: Apache-2.0
  *
  * Change Logs:
  * Date           Author       Notes
  * 2022-04-19     Meco Man     first version
+ * 2022-07-26     liYony       Perfect PWM (docking of complementary outputs)
  */
 #include <Arduino.h>
 #include <board.h>
@@ -23,15 +24,15 @@ const pin_map_t pin_map_table[]=
     {D0}, /* RX */
     {D1}, /* TX */
     {D2, GET_PIN(A,10)},
-    {D3, GET_PIN(B,3), "pwm2", 2}, /* PWM */
+    {D3, GET_PIN(B,3), "pwm2", 2}, /* PWM2-CH2 */
     {D4, GET_PIN(B,5)},
-    {D5, GET_PIN(B,4), "pwm3", 1}, /* PWM */
-    {D6, GET_PIN(B,10), "pwm2", 3}, /* PWM */
+    {D5, GET_PIN(B,4), "pwm3", 1}, /* PWM3-CH1 */
+    {D6, GET_PIN(B,10), "pwm2", 3}, /* PWM2-CH3 */
     {D7, GET_PIN(A,8)},
     {D8, GET_PIN(A,9)},
-    {D9, GET_PIN(C,7), "pwm3", 2}, /* PWM */
-    {D10, GET_PIN(B,6)},
-    {D11, GET_PIN(A,7)},
+    {D9, GET_PIN(C,7), "pwm3", 2}, /* PWM3-CH2 */
+    {D10, GET_PIN(B,6), "pwm4", 1}, /* PWM4-CH1 */
+    {D11, GET_PIN(A,7), "pwm1", -1}, /* PWM1-CH1N */
     {D12, GET_PIN(A,6)},
     {D13, GET_PIN(A,5)},
     {D14}, /* I2C1-SDA */