test-modbus/test.c

   1 #include "util.h"
   2 #include "modbus.h"
   3
   4 #include <libopencm3/cm3/cortex.h>
   5 #include <libopencm3/cm3/nvic.h>
   6 #include <libopencm3/cm3/systick.h>
   7 #include <libopencm3/stm32/rcc.h>
   8 #include <libopencm3/stm32/gpio.h>
   9 #include <libopencm3/stm32/usart.h>
  10 #include <libopencm3/stm32/timer.h>
  11
  12 static void clock_setup(void)
  13 {
  14         rcc_clock_setup_in_hse_8mhz_out_72mhz();
  15
  16         rcc_periph_clock_enable(RCC_GPIOA);
  17         rcc_periph_clock_enable(RCC_GPIOB);
  18         rcc_periph_clock_enable(RCC_GPIOC);
  19         rcc_periph_clock_enable(RCC_USART2);
  20         rcc_periph_clock_enable(RCC_TIM2);
  21         rcc_periph_clock_enable(RCC_TIM4);
  22
  23         rcc_periph_reset_pulse(RST_GPIOA);
  24         rcc_periph_reset_pulse(RST_GPIOB);
  25         rcc_periph_reset_pulse(RST_GPIOC);
  26         rcc_periph_reset_pulse(RST_USART2);
  27         rcc_periph_reset_pulse(RST_TIM2);
  28         rcc_periph_reset_pulse(RST_TIM4);
  29 }
  30
  31 static void gpio_setup(void)
  32 {
  33         // PC13 = BluePill LED
  34         gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO13);
  35         gpio_clear(GPIOC, GPIO13);
  36 }
  37
  38 static volatile u32 ms_ticks;
  39
  40 void sys_tick_handler(void)
  41 {
  42         ms_ticks++;
  43 }
  44
  45 static void tick_setup(void)
  46 {
  47         systick_set_frequency(1000, 72000000);
  48         systick_counter_enable();
  49         systick_interrupt_enable();
  50 }
  51
  52 static void delay_ms(uint ms)
  53 {
  54         u32 start_ticks = ms_ticks;
  55         while (ms_ticks - start_ticks < ms)
  56                 ;
  57 }
  58
  59 static void usart_setup(void)
  60 {
  61 #if 0
  62         gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO_USART2_TX);
  63
  64         usart_set_baudrate(USART2, 9600);
  65         usart_set_databits(USART2, 8);
  66         usart_set_stopbits(USART2, USART_STOPBITS_1);
  67         usart_set_mode(USART2, USART_MODE_TX_RX);
  68         usart_set_parity(USART2, USART_PARITY_NONE);
  69         usart_set_flow_control(USART2, USART_FLOWCONTROL_NONE);
  70
  71         usart_enable(USART2);
  72 #endif
  73 }
  74
  75 int main(void)
  76 {
  77         clock_setup();
  78         gpio_setup();
  79         tick_setup();
  80         usart_setup();
  81
  82         modbus_init();
  83         cm_enable_interrupts();         // FIXME: Needed?
  84
  85 #if 0
  86         timer_set_prescaler(TIM4, 7);   // clock = 72 MHz / 8 = 18 MHz  FIXME!
  87         timer_set_mode(TIM4, TIM_CR1_CKD_CK_INT, TIM_CR1_CMS_EDGE, TIM_CR1_DIR_UP);
  88         timer_disable_preload(TIM4);
  89         timer_set_period(TIM4, 255);    // PWM frequency = 18 MHz / 256 = 70.3125 kHz
  90         timer_set_oc_mode(TIM4, TIM_OC1, TIM_OCM_PWM1);
  91         timer_set_oc_value(TIM4, TIM_OC1, 128);
  92         timer_set_oc_polarity_high(TIM4, TIM_OC1);
  93         timer_enable_counter(TIM4);
  94         timer_enable_oc_output(TIM4, TIM_OC1);
  95 #endif
  96
  97         gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO6);
  98         // gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO8);
  99
 100         for (;;) {
 101                 //gpio_toggle(GPIOC, GPIO13);
 102                 delay_ms(50);
 103                 // gpio_toggle(GPIOA, GPIO8);
 104                 //timer_set_oc_mode(TIM4, TIM_OC1, TIM_OCM_FORCE_LOW);
 105                 //delay_ms(50);
 106                 //timer_set_oc_mode(TIM4, TIM_OC1, TIM_OCM_FORCE_HIGH);
 107                 modbus_loop();
 108         }
 109
 110         return 0;
 111 }