【AT-START-F425 Review】No.03 Debugging serial port, timer and main system frequency

韵湖葱白

【AT-START-F425 Review】No.03 Debugging serial port, timer and main system frequency [Copy link]

 

## Preface In the previous section, we set up the development environment and ran the main program. In the previous section, we praised the organization of Arteli's website. In this section, we praise Arteli's official demo for being the most detailed. Thumbs up. Next, I started to criticize, -_-. - **The official user manual PDF does not even have a directory on the left column. It is so troublesome to find it. ** - **In the official driver file, at32f425_xx.c does not directly include at32f425_xx.h. The underlying driver should be more direct and not so troublesome** - **at32f425_conf.h file, wouldn't it be better to list the comments in the header file directly? It is unnecessary to make a macro definition. ** >``` >#define ACC_MODULE_ENABLED >... >#ifdef ACC_MODULE_ENABLED >#include "at32f425_acc.h" >#endif >``` - **It's a good name for [Clock Tree], but it has to be called [Clock Structure Diagram]** In this section, we get the time base that drives the entire OS, that is, the timer, and print the main clock frequency of the system through the debug serial port. Arteli's resource numbering starts from 1, which is consistent with the expression of STM32; However, Arteli's function naming method is underscore-style, but the timer is not written as timer but tmr, which obviously does not understand the true meaning of underscore-style naming. ## The timer uses timer 2 to drive the entire OS, and the time base is 1ms. Timer initialization: ``` void timer2_init(void) { tmr_reset(TMR2); crm_periph_clock_enable(CRM_TMR2_PERIPH_CLOCK, TRUE); timerx_init(TMR2, 9599, 9); // 10KHz 1ms tmr_interrupt_enable(TMR2, TMR_OVF_INT, TRUE); n vic_irq_enable(TMR2_GLOBAL_IRQn, 6, 0); } ``` `` static void timerx_init(tmr_type* TIMx, uint16_t prescaler, uint16_t period) { timerx_init_full(TIMx, prescaler, period, TMR_CLOCK_DIV1, TMR_COUNT_UP, 0); } static void timerx_init_full(tmr_type* TIMx, uint16_t prescaler, uint16_t period, uint16_t clock_div, uint16_t counter_mode, uint8_t repetition_counter) { tmr_base_init(TIMx, period, prescaler); tmr_repetition_counter_set(TIMx, repetition_counter); tmr_cnt_dir_set(TIMx, TMR_COUNT_UP); tmr_clock_source_div_set(TIMx, clock_div); tmr_counter_enable(TIMx, TRUE); } ``` ## Debug serial port The serial port initialization is similar, use serial port 1, PA9 to send, the official demo has it. ``` void uart1_init(uint32_t baudrate) { usart_type* com = USART1; gpio_init_type gpio_init_struct; usart_reset(com); crm_periph_clock_enable(CRM_USART1_PERIPH_CLOCK, TRUE); crm_periph_clock_enable(CRM_GPIOA_PERIPH_CLOCK, TRUE); ///< USART1_TX PA.9 gpio_default_para_init(&gpio_init_struct); gpio_init_struct.gpio_drive_strength = GPIO_DRIVE_STRENGTH_STRONGER; gpio_init_struct.gpio_out_type = GPIO_OUTPUT_PUSH_PULL; gpio_init_struct.gpio_mode = GPIO_MODE_MUX; gpio_init _struct.gpio_pins = GPIO_PINS_9; gpio_init_struct.gpio_pull = GPIO_PULL_NONE; gpio_init(GPIOA, &gpio_init_struct); gpio_pin_mux_config(GPIOA, GPIO_PINS_SOURCE9, GPIO_MUX_1); usart_init(com, baudrate, USART_DATA_8BITS, USART_STOP_1_BIT ); usart_transmitter_enable(com, TRUE); usart_enable(com, TRUE); } `` supports printf, which can also be found in this demo: ``` #ifdef USING_PRINTF #define PRINTF_UART USART1 #pragma import(__use_no_semihosting) //Support functions required by the standard library struct __FILE { int handle; /* Whatever you require here. If the only file you are using is */ /* standard output using printf() for debugging, no file handling */ /* is required. */ }; /* FILE is typedef' d in stdio.h. */ FILE __stdout; void _sys_exit(int x) { x = x; } /* retarget the C library printf function to the USART */ int fputc(int ch, FILE *f) { usart_data_transmit(PRINTF_UART,(uint8_t)ch); while(RESET == usart_flag_get(PRINTF_UART, USART_TDBE_FLAG)); return ch; } ``` ## Frequency printing The interface of Arteli is similar to that of STM32, `crm_clocks_freq_get`.接口示例： ``` crm_clocks_freq_type clock; crm_clocks_freq_get(&clock); ``` 打印代码示例： ``` #if defined(AT32) crm_clocks_freq_type clock; crm_clocks_freq_get(&clock); freq[0] = clock.sclk_freq/1000000; freq[1] = clock.ahb_freq/1000000; freq[2] = clock.apb1_freq/1000000; freq[3] = clock.apb2_freq/1000000; freq[4] = clock.adc_freq/1000000; #endif printf("freq: SYS[%d MHz] AHB[%d MHz] APB1[%d MHz] APB2[%d MHz] ADC[%d MHz]\r\n", freq[0], freq[1], freq[2], freq[3], freq[4]); #endif ``` ## Result demonstration `` freq: SYS[96 MHz] AHB[96 MHz] APB 1[96 MHz] APB2[96 MHz] ADC[48 MHz] freq: SYS[96 MHz] AHB[96 MHz] APB1[96 MHz] APB2[96 MHz] ADC[48 MHz] freq: SYS[96 MHz] AHB[96 MHz] APB1[96 MHz] APB2[96 MHz] ADC[48 MHz]SY freq: S[96 MHz] AHB[96 MHz] APB1[96 MHz] APB2[96 MHz] ADC[48 MHz] freq: SYS[96 MHz] AHB[96 MHz] APB1[96 MHz] APB2[96 MHz] ADC[48 MHz] freq: SYS[96 MHz] AHB[96 MHz] APB1[96 MHz] APB2[96 MHz] ADC[48 MHz] freq: SYS[96 MHz] AHB[96 MHz] APB1[96 MHz] APB2[96 MHz] ADC[48 MHz] freq: SYS[96 MHz] AHB[96 MHz] APB1[96 MHz] APB2[96 MHz] ADC[48 MHz] ``` 

lugl4313820

Maybe it's to distinguish each one's characteristics, or because of patent reasons, so each chip is named differently, and the meanings are quite different, which is a bit dizzying.