test-opencm3/test.c

   1 #include "util.h"
   2 #include "ds18b20.h"
   3
   4 #include <libopencm3/cm3/nvic.h>
   5 #include <libopencm3/cm3/systick.h>
   6 #include <libopencm3/stm32/rcc.h>
   7 #include <libopencm3/stm32/gpio.h>
   8 #include <libopencm3/stm32/timer.h>
   9 #include <libopencm3/stm32/usart.h>
  10
  11 static void clock_setup(void)
  12 {
  13         rcc_clock_setup_in_hse_8mhz_out_72mhz();
  14
  15         rcc_periph_clock_enable(RCC_GPIOA);
  16         rcc_periph_clock_enable(RCC_GPIOB);
  17         rcc_periph_clock_enable(RCC_GPIOC);
  18         rcc_periph_clock_enable(RCC_USART1);
  19         rcc_periph_clock_enable(RCC_TIM3);
  20         rcc_periph_clock_enable(RCC_TIM4);
  21         rcc_periph_clock_enable(RCC_DMA1);
  22 }
  23
  24 static void gpio_setup(void)
  25 {
  26         // PC13 = BluePill LED
  27         gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO13);
  28         gpio_clear(GPIOC, GPIO13);
  29
  30         // PC14 = bypass LED*
  31         gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO14);
  32         gpio_set(GPIOC, GPIO14);
  33
  34         // PC15 = bypass opto-coupler
  35         gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO15);
  36         gpio_clear(GPIOC, GPIO15);
  37 }
  38
  39 static volatile u32 ms_ticks;
  40
  41 void sys_tick_handler(void)
  42 {
  43         ms_ticks++;
  44 }
  45
  46 static void tick_setup(void)
  47 {
  48         systick_set_frequency(1000, 72000000);
  49         systick_counter_enable();
  50         systick_interrupt_enable();
  51 }
  52
  53 static void delay_ms(uint ms)
  54 {
  55         u32 start_ticks = ms_ticks;
  56         while (ms_ticks - start_ticks < ms)
  57                 ;
  58 }
  59
  60 static void usart_setup(void)
  61 {
  62         gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO_USART1_TX);
  63
  64         usart_set_baudrate(USART1, 115200);
  65         usart_set_databits(USART1, 8);
  66         usart_set_stopbits(USART1, USART_STOPBITS_1);
  67         usart_set_mode(USART1, USART_MODE_TX_RX);
  68         usart_set_parity(USART1, USART_PARITY_NONE);
  69         usart_set_flow_control(USART1, USART_FLOWCONTROL_NONE);
  70
  71         usart_enable(USART1);
  72 }
  73
  74 static bool bypass_active;
  75 static byte pwm;
  76
  77 static void show_temperature(void)
  78 {
  79         debug_putc('#');
  80         for (uint i=0; ds_sensors[i].address[0]; i++) {
  81                 debug_putc(' ');
  82                 int t = ds_sensors[i].current_temp;
  83                 if (t == DS_TEMP_UNKNOWN)
  84                         debug_puts("---.---");
  85                 else
  86                         debug_printf("%3d.%03d", t / 1000, t % 1000);
  87         }
  88         debug_printf(" %d", bypass_active);
  89         debug_printf(" %d", pwm);
  90         debug_puts("\r\n");
  91 }
  92
  93 static void pwm_init(void)
  94 {
  95         timer_set_prescaler(TIM4, 3);   // clock = 72 MHz / 2 = 36 MHz
  96         timer_set_mode(TIM4, TIM_CR1_CKD_CK_INT, TIM_CR1_CMS_EDGE, TIM_CR1_DIR_UP);
  97         timer_disable_preload(TIM4);
  98         timer_set_period(TIM4, 255);    // PWM frequency = 18 MHz / 256 = 70.3125 kHz   FIXME
  99         timer_set_oc_mode(TIM4, TIM_OC1, TIM_OCM_PWM1);
 100         timer_set_oc_value(TIM4, TIM_OC1, 1);
 101         pwm = 1;
 102         /*
 103          *      1       0.03
 104          *      4       0.48
 105          *      8       1.54
 106          *      12      2.71
 107          *      16      3.99
 108          *      24      6.34
 109          *      32      7.85
 110          *      64      7.95
 111          *      128     8.02
 112          *      255
 113          */
 114         timer_set_oc_polarity_high(TIM4, TIM_OC1);
 115         timer_enable_counter(TIM4);
 116         timer_enable_oc_output(TIM4, TIM_OC1);
 117
 118         gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO6);
 119 }
 120
 121 int main(void)
 122 {
 123         clock_setup();
 124         gpio_setup();
 125         tick_setup();
 126         usart_setup();
 127         pwm_init();
 128
 129         ds_init();
 130
 131         byte cycles = 0;
 132         for (;;) {
 133                 gpio_toggle(GPIOC, GPIO13);
 134                 delay_ms(100);
 135                 ds_step();
 136                 if (usart_get_flag(USART1, USART_SR_RXNE)) {
 137                         uint ch = usart_recv(USART1);
 138                         if (ch == 'B') {
 139                                 bypass_active = 1;
 140                                 gpio_set(GPIOC, GPIO15);        // opto-coupler
 141                                 gpio_clear(GPIOC, GPIO14);      // LED
 142                         } else if (ch == 'b') {
 143                                 bypass_active = 0;
 144                                 gpio_clear(GPIOC, GPIO15);      // opto-coupler
 145                                 gpio_set(GPIOC, GPIO14);        // LED
 146                         } else if (ch >= '0' && ch <= '9') {
 147                                 pwm = 3*(ch - '0') + 1;
 148                                 /*
 149                                  *      ch      pwm       %
 150                                  *      0         1       0
 151                                  *      1         4       0
 152                                  *      2         7      18
 153                                  *      3        10      31
 154                                  *      4        13      44
 155                                  *      5        16      57
 156                                  *      6        19      71
 157                                  *      7        22      84
 158                                  *      8        25      97
 159                                  *      9        28     100
 160                                  *
 161                                  *      % = pwm*4.389 - 12.723
 162                                  */
 163                                 timer_set_oc_value(TIM4, TIM_OC1, pwm);
 164                         }
 165                 }
 166                 if (cycles++ >= 50) {
 167                         cycles = 0;
 168                         show_temperature();
 169                 }
 170         }
 171
 172         return 0;
 173 }