目录
K210的UART模块支持全双工通信，可以同时进行数据的发送和接收。在K210上使用UART串口通信，你可以连接外部设备，如传感器、显示器、WiFi模块等，实现数据的交换和控制。
K210-UART串口通信相关函数：
1.machine.UART()：该函数用于初始化一个UART串口对象。你可以指定串口的编号（如UART1）、波特率、数据位、校验位、停止位、TX引脚和RX引脚等参数。
import machine
# 初始化串口
uart = machine.UART(1, baudrate=115200, tx=12, rx=13)在这个示例中，我们使用machine.UART()函数初始化了一个串口对象，指定了串口的编号（1）、波特率（115200）、TX引脚（12）和RX引脚（13）。
或者可以：
machine.UART(uart,baudrate,bits,parity,stop,timeout, read_buf_len)
2.uart.write()：该函数用于向串口发送数据。你可以发送字符串或者字节数据。
# 发送数据
uart.write('Hello, UART!')3.uart.read()：该函数用于从串口接收数据。它会阻塞程序直到接收到指定数量的数据或者超时
# 接收数据
data = uart.read(10)
print(data)4.uart.any()：该函数用于检查串口是否有未读取的数据。如果有，返回值为True；否则返回False。
# 检查是否有未读取的数据
if uart.any():
data = uart.read()
print(data)5.uart.flush()：该函数用于清空串口的缓冲区，将所有未读取的数据丢弃
使用K210串口的时候需要映射引脚：
# IO6→RX1，IO7→TX1
fm.register(6, fm.fpioa.UART1_RX, force=True)
fm.register(7, fm.fpioa.UART1_TX, force=True)
K210与STM32串口通信
K210与STM32串口通信发送分为两种：一种是发送单字节，一种是发送数据包。因为发送的数据不一样，从而K210的代码和STM32的代码都是不一样的。
本篇文章只涉及K210发送给STM32。
发送单字节：
K210端
from machine import UART, Timer
from fpioa_manager import fm
#映射串口引脚
fm.register(6, fm.fpioa.UART1_RX, force=True)
fm.register(7, fm.fpioa.UART1_TX, force=True)
while True:
text=uart.read() #读取数据
if text: #如果读取到了数据
uart.write('1')
STM32端
void Usart3_Init(unsigned int baud)
{
GPIO_InitTypeDef gpio_initstruct;
USART_InitTypeDef usart_initstruct;
NVIC_InitTypeDef nvic_initstruct;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);
//PA2 TXD
gpio_initstruct.GPIO_Mode = GPIO_Mode_AF_PP;
gpio_initstruct.GPIO_Pin = GPIO_Pin_10;
gpio_initstruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &gpio_initstruct);
//PA3 RXD
gpio_initstruct.GPIO_Mode = GPIO_Mode_IN_FLOATING;
gpio_initstruct.GPIO_Pin = GPIO_Pin_11;
gpio_initstruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &gpio_initstruct);
usart_initstruct.USART_BaudRate = baud;
usart_initstruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
usart_initstruct.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
usart_initstruct.USART_Parity = USART_Parity_No;
usart_initstruct.USART_StopBits = USART_StopBits_1;
usart_initstruct.USART_WordLength = USART_WordLength_8b;
USART_Init(USART3, &usart_initstruct)；
USART_Cmd(USART3, ENABLE);
USART_ITConfig(USART3, USART_IT_RXNE, ENABLE);
nvic_initstruct.NVIC_IRQChannel = USART2_IRQn;
nvic_initstruct.NVIC_IRQChannelCmd = ENABLE;
nvic_initstruct.NVIC_IRQChannelPreemptionPriority = 0;
nvic_initstruct.NVIC_IRQChannelSubPriority = 1;
NVIC_Init(&nvic_initstruct);
}
if(USART_ReceiveData(USART3)=='1')//K210
{
numbert++;
}
发送数据包
K210端
def str_int(data_str):
bb = binascii.hexlify(data_str)
bb = str(bb)[2:-1]
#print(bb)
#print(type(bb))
hex_1 = int(bb[0])*16
hex_2 = int(bb[1],16)
return hex_1+hex_2
def send_data(x,y,w,h,msg):
start = 0x24
end = 0x23
length = 5
class_num = 0x05 #例程编号
class_group = 0xBB #例程组
data_num = 0x00 #数据量
fenge = 0x2c #逗号
crc = 0 #校验位
data = [] #数据组
#参数都为0
if x==0 and y==0 and w==0 and h ==0:
pass
else:
#x(小端模式)
low = x & 0xFF #低位
high = x >> 8& 0xFF #高位
data.append(low)
data.append(fenge) #增加","
data.append(high)
data.append(fenge) #增加","
#y(小端模式)
low = y & 0xFF #低位
high = y >> 8& 0xFF #高位
data.append(low)
data.append(fenge) #增加","
data.append(high)
data.append(fenge) #增加","
#w(小端模式)
low = w & 0xFF #低位
high = w >> 8& 0xFF #高位
data.append(low)
data.append(fenge) #增加","
data.append(high)
data.append(fenge) #增加","
#h(小端模式)
low = h & 0xFF #低位
high = h >> 8& 0xFF #高位
data.append(low)
data.append(fenge) #增加","
data.append(high)
data.append(fenge) #增加","
if msg !=None:
#msg
for i in range(len(msg)):
hec = str_int(msg[i])
data.append(hec)
data.append(fenge) #增加","
#print(data)
data_num = len(data)
length += len(data)
#print(length)
send_merr = [length,class_num,class_group,data_num]
for i in range(data_num):
send_merr.append(data[i])
#print(send_merr)
#不加上CRC位，进行CRC运算
for i in range(len(send_merr)):
crc +=send_merr[i]
crc = crc%256
send_merr.insert(0,start) #插入头部
send_merr.append(crc)
send_merr.append(end)
#print(send_merr)
global send_buf
send_buf = send_merrSTM32端
char buf_msg[100] = {'\0'};
u8 new_flag = 0;
u8 r_index = 0;
u16 buf_crc = 0;
u8 tou_flag = 0;
u8 len_flag = 0;
u8 buf_len = 0;
char data[50];
void recv_k210msg(uint8_t recv_msg)
{
if (recv_msg == '$')
{
new_flag = 1;
}
if (recv_msg == '#')
{
if (buf_len == r_index)
{
new_flag = 0;
tou_flag = 0;
len_flag = 0;
buf_crc -= buf_msg[r_index - 1];
buf_crc %= 256;
if (buf_crc == buf_msg[r_index - 1])
{
deal_recvmsg();
}
else
{
r_index = 0;
buf_crc = 0;
}
}
}
if (new_flag == 1)
{
if (recv_msg == '$' && tou_flag == 0)
{
tou_flag = 1;
}
else
{
buf_msg[r_index++] = recv_msg;
buf_crc += recv_msg;
if (len_flag == 0)
{
buf_len = buf_msg[0];
len_flag = 1;
}
}
}
}
void deal_recvmsg(void)
{
u8 index, data_i = 0;
u8 eg_num = buf_msg[1];
u8 number = buf_msg[3];
u8 i_duo = 0;
if (r_index != buf_len)
{
buf_len = 0;
return;
}
for (index = 0; index < number; index++)
{
if (buf_msg[4 + index] == 0x2c && i_duo == 0)
{
i_duo = 1;
continue;
}
data[data_i++] = buf_msg[4 + index];
i_duo = 0;
}
buf_crc = 0;
r_index = 0;
memset(buf_msg, 0, sizeof(buf_msg));
deal_data(eg_num);
}
void deal_data(u8 egnum)
{
u16 x, y, w, h;
u8 msg[20] = {'\0'};
u8 icopy = 0;
u16 id = 999;
switch (egnum)
{
case 1:
case 5:
case 6:
x = data[1] << 8 | data[0];
y = data[3] << 8 | data[2];
w = data[5] << 8 | data[4];
h = data[7] << 8 | data[6];
break;
case 2:
case 3:
x = data[1] << 8 | data[0];
y = data[3] << 8 | data[2];
w = data[5] << 8 | data[4];
h = data[7] << 8 | data[6];
while (*(data + 8 + icopy) != '\0')
{
msg[icopy] = *(data + 8 + icopy);
icopy++;
}
break;
case 4:
x = data[1] << 8 | data[0];
y = data[3] << 8 | data[2];
w = data[5] << 8 | data[4];
h = data[7] << 8 | data[6];
id = data[8] << 8 | data[9];
while (*(data + 10 + icopy) != '\0')
{
msg[icopy] = *(data + 10 + icopy);
icopy++;
}
break;
case 7:
case 8:
x = data[1] << 8 | data[0];
y = data[3] << 8 | data[2];
w = data[5] << 8 | data[4];
h = data[7] << 8 | data[6];
id = data[8];
break;
case 9:
x = data[1] << 8 | data[0];
y = data[3] << 8 | data[2];
w = data[5] << 8 | data[4];
h = data[7] << 8 | data[6];
while (*(data + 8 + icopy) != '\0')
{
msg[icopy] = *(data + 8 + icopy);
icopy++;
}
break;
case 10:
case 11:
id = data[0];
break;
}
k210_msg.class_n = egnum;
k210_msg.x = x;
k210_msg.y = y;
k210_msg.w = w;
k210_msg.h = h;
k210_msg.id = id;
strcpy((char*)k210_msg.msg_msg, (char*)msg);
memset(data, 0, sizeof(data));
}
void USART2_IRQHandler(void)
{
uint8_t Rx2_Temp;
if (USART_GetITStatus(USART2, USART_IT_RXNE) != RESET)
{
Rx2_Temp = USART_ReceiveData(USART2);
recv_k210msg(Rx2_Temp);
}
}
有读者看到这里可能会想问，能不能用单字节的方式发送字符串，STM32中USART_ReceiveData(USART3)=='1'此处没法等于字符串。