ESP8266 PWM源文件

/****************************************************************************** * Copyright 2013-2014 Espressif Systems (Wuxi) * * FileName: pwm.c * * Description: pwm driver * * Modification history: * 2014/5/1, v1.0 create this file. *******************************************************************************/ #include "ets_sys.h" #include "os_type.h" #include "osapi.h" #include "user_interface.h" #include "pwm.h" #define pwm_dbg_printf //os_printf struct pwm_single_param { uint16 gpio_set; uint16 gpio_clear; uint32 h_time; }; struct pwm_param pwm; LOCAL bool update_flg = 0; //update finished flag LOCAL bool init_flg = 0; //first update flag LOCAL uint8 pwm_chn_num = 0; LOCAL uint8 pwm_out_io_num[8] = {0}; //each channel gpio number LOCAL bool pwm_stop_flag = 0; //start/stop frc1 timer LOCAL struct pwm_single_param local_single[8 + 1]; //local_single param, on-changing LOCAL uint8 local_channel = 0; //local_channel value LOCAL struct pwm_single_param run_pwm_single[2][8 + 1]; //running para, two sets LOCAL uint8 run_pwm_channel[2]; LOCAL uint8 run_pwm_toggle = 0; LOCAL struct pwm_single_param *pwm_single; LOCAL uint8 pwm_channel; LOCAL uint8 pwm_current_channel = 0; //current pwm channel in pwm_tim1_intr_handler LOCAL uint16 pwm_gpio = 0; //all pwm gpio bits static u32 last_gpio_hdl_frc1_tick = 0x7fffff; //XXX: 0xffffffff/(80000000/16)=35A //IMPORTANT: t mus be u32 type. u16, 450~800, err!!!!!!!!!!! #define US_TO_RTC_TIMER_TICKS(t) \ ((t) ? \ (((t) > 0x35A) ? \ (((t)>>2) * ((APB_CLK_FREQ>>4)/250000) + ((t)&0x3) * ((APB_CLK_FREQ>>4)/1000000)) : \ (((t) *(APB_CLK_FREQ>>4)) / 1000000)) : \ 0) #define FRC1_ENABLE_TIMER BIT7 //TIMER PREDIVED MODE typedef enum { DIVDED_BY_1 = 0, //timer clock DIVDED_BY_16 = 4, //divided by 16 DIVDED_BY_256 = 8, //divided by 256 } TIMER_PREDIVED_MODE; typedef enum { //timer interrupt mode TM_LEVEL_INT = 1, // level interrupt TM_EDGE_INT = 0, //edge interrupt } TIMER_INT_MODE; // sort all channels' h_time,small to big LOCAL void ICACHE_FLASH_ATTR pwm_insert_sort(struct pwm_single_param pwm[], uint8 n) { uint8 i; for (i = 1; i < n; i++) { if (pwm[i].h_time < pwm[i - 1].h_time) { int8 j = i - 1; struct pwm_single_param tmp; os_memcpy(&tmp, &pwm[i], sizeof(struct pwm_single_param)); os_memcpy(&pwm[i], &pwm[i - 1], sizeof(struct pwm_single_param)); while (tmp.h_time < pwm[j].h_time) { os_memcpy(&pwm[j + 1], &pwm[j], sizeof(struct pwm_single_param)); j--; if (j < 0) { break; } } os_memcpy(&pwm[j + 1], &tmp, sizeof(struct pwm_single_param)); } } } #define LOW_LIMIT (6) void ICACHE_FLASH_ATTR pwm_start(void) { uint8 i, j; // step 1: init PWM_CHANNEL+1 channels param for (i = 0; i < pwm_chn_num; i++) { //uint32 us = pwm.period * pwm.duty[i] / PWM_DEPTH; //calc single channel us time //local_single[i].h_time = US_TO_RTC_TIMER_TICKS(us); //calc h_time to write FRC1_LOAD_ADDRESS local_single[i].h_time = (pwm.period * pwm.duty[i]*5)/PWM_DEPTH; //calc h_time to write FRC1_LOAD_ADDRESS if(local_single[i].h_time<LOW_LIMIT) local_single[i].h_time = LOW_LIMIT; local_single[i].gpio_set = 0; //don't set gpio local_single[i].gpio_clear = 1 << pwm_out_io_num[i]; //clear single channel gpio } local_single[pwm_chn_num].h_time = US_TO_RTC_TIMER_TICKS(pwm.period); //calc pwm.period channel us time local_single[pwm_chn_num].gpio_set = pwm_gpio; //set all channels' gpio local_single[pwm_chn_num].gpio_clear = 0; //don't clear gpio pwm_dbg_printf("init\n"); for (i = 0; i < 4; i++) { pwm_dbg_printf("set:%x ",local_single[i].gpio_set); pwm_dbg_printf("clr:%x ",local_single[i].gpio_clear); pwm_dbg_printf("htm:%u ",local_single[i].h_time); pwm_dbg_printf("\n"); } // step 2: sort, small to big pwm_insert_sort(local_single, pwm_chn_num + 1); //time sort small to big, local_channel = pwm_chn_num + 1; //local channel number is PWM_CHANNEL+1 pwm_dbg_printf("sort\n"); for (i = 0; i < local_channel; i++) { pwm_dbg_printf("set:%x ",local_single[i].gpio_set); pwm_dbg_printf("clr:%x ",local_single[i].gpio_clear); pwm_dbg_printf("htm:%u ",local_single[i].h_time); pwm_dbg_printf("\n"); } // step 2.5: low limit of duty diff is 6. for (i =1 ; i <= pwm_chn_num; i++) { u32 tmp = local_single[i].h_time - local_single[i - 1].h_time; if ( tmp < 6 ) { if ( tmp < 3 ) local_single[i].h_time = local_single[i - 1].h_time; else local_single[i].h_time = local_single[i - 1].h_time+6; } } pwm_dbg_printf("remove low limit\n"); for (i = 0; i < local_channel; i++) { pwm_dbg_printf("set:%x ",local_single[i].gpio_set); pwm_dbg_printf("clr:%x ",local_single[i].gpio_clear); pwm_dbg_printf("htm:%u ",local_single[i].h_time); pwm_dbg_printf("\n"); } // step 3: combine same duty channels for (i = pwm_chn_num; i > 0; i--) { if (local_single[i].h_time == local_single[i - 1].h_time) { local_single[i - 1].gpio_set |= local_single[i].gpio_set; local_single[i - 1].gpio_clear |= local_single[i].gpio_clear; //copy channel j param to channel j-1 param for (j = i + 1; j < local_channel; j++) { os_memcpy(&local_single[j - 1], &local_single[j], sizeof(struct pwm_single_param)); } local_channel--; } } pwm_dbg_printf("combine\n"); for (i = 0; i < local_channel; i++) { pwm_dbg_printf("set:%x ",local_single[i].gpio_set); pwm_dbg_printf("clr:%x ",local_single[i].gpio_clear); pwm_dbg_printf("htm:%u ",local_single[i].h_time); pwm_dbg_printf("\n"); } // step 4: calc delt time for (i = local_channel - 1; i > 0; i--) { local_single[i].h_time -= local_single[i - 1].h_time; } // step 5: last channel needs to clean local_single[local_channel - 1].gpio_clear = 0; // step 6: if first channel duty is 0, remove it if (local_single[0].h_time == 0) { local_single[local_channel - 1].gpio_set &= ~local_single[0].gpio_clear; local_single[local_channel - 1].gpio_clear |= local_single[0].gpio_clear; //copy channel i param to channel i-1 param for (i = 1; i < local_channel; i++) { os_memcpy(&local_single[i - 1], &local_single[i], sizeof(struct pwm_single_param)); } local_channel--; } //local OR saved ? pwm_dbg_printf("remove 1st 0\n"); for (i = 0; i < local_channel; i++) { pwm_dbg_printf("set:%x ",local_single[i].gpio_set); pwm_dbg_printf("clr:%x ",local_single[i].gpio_clear); pwm_dbg_printf("htm:%u ",local_single[i].h_time); pwm_dbg_printf("\n"); }