本帖最后由 masterqqq 于 2020-8-12 10:15 编辑
调试环境：MPLAB x IDE5.40 + XC8
项目属性的PKOB 通讯速率需要设置位0.75M才能正常下载
USART输出测试
- #define F_CPU (4000000UL) /* using default clock 4MHz*/
- #define USART1_BAUD_RATE(BAUD_RATE) ((float)(64 * 4000000 / (16 * (float)BAUD_RATE)) +0.5)
- #include <avr/io.h>
- #include <util/delay.h>
- #include <string.h>
- void USART1_init(void);
- void USART1_sendChar(char c);
- void USART1_sendString(char str[]);
- void USART1_init(void)
- {
- PORTC.DIRSET = PIN0_bm; /* set pin 0 of PORT C (TXd) as output*/
- PORTC.DIRCLR = PIN1_bm; /* set pin 1 of PORT C (RXd) as input*/
-
- USART1.BAUD = (uint16_t)USART1_BAUD_RATE(9600); /* set the baud rate*/
-
- USART1.CTRLC = USART_CHSIZE0_bm
- | USART_CHSIZE1_bm; /* set the data format to 8-bit*/
-
- USART1.CTRLB |= USART_TXEN_bm; /* enable transmitter*/
-
- }
- void USART1_sendChar(char c)
- {
- while(!(USART1.STATUS & USART_DREIF_bm))
- {
- ;
- }
-
- USART1.TXDATAL = c;
- }
- void USART1_sendString(char str[])
- {
- for(int i = 0; i < strlen(str); i++)
- {
- USART1_sendChar(str[i]);
- }
- }
- int main(void)
- {
- char str[40] ="Curiosity Nano USART ";
- USART1_init();
-
- while (1)
- {
- USART1_sendString(str);
- _delay_ms(1000);
- }
- }
| 
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