FLEXPWM EXT_SYNC

[Motafared]

I am Trying to create 8  synced PWM using IMXRT1062 on TEENSY4 board 
I created master PWM to sync them to it using XBAR and EXT_SYNC
i could build the PWM easily but i couldn't send the the trigger from the master pwm to the others  
i tested it between different modules but everytime i fail ,The slave PWM keep counting to the end of its 16 bit counter without receiving EXT_SYNC signal  and then wrap again from zero 
i even tried to send the trigger signal to external physical pin as a debugging but i could not see it on the scope 
can any one help me what i messed 
i am using ARDUINO IDE

  // ====== FLEXPWM2 Setup: PWM2_0_A on Pin 4  slave======

  // Enable clock for FLEXPWM2 (CG9: bits 19-18)

  CCM_CCGR4 |= (3 << 18);  // FLEXPWM2 for Pin 4 (PWM2_0_A)

   // Set pin 4 to ALT1 = FLEXPWM2_PWM0_A

  CORE_PIN4_CONFIG = 1;

  FLEXPWM2_MCTRL &= ~(FLEXPWM_MCTRL_RUN(1 << 0)); //stop it at the begining

  FLEXPWM2_SM0CTRL2 = FLEXPWM_SMCTRL2_INDEP|FLEXPWM_SMCTRL2_INIT_SEL(3); //independent + init select = EXT_SYNC

  FLEXPWM2_SM0CTRL  = FLEXPWM_SMCTRL_PRSC(0) | FLEXPWM_SMCTRL_FULL;

  FLEXPWM2_SM0INIT  = 0;

  FLEXPWM2_SM0VAL0  = 0;

  FLEXPWM2_SM0VAL1  = 0;

  FLEXPWM2_SM0VAL2  = 0+PHASE;

  FLEXPWM2_SM0VAL3  = (DUTY+PHASE);

  FLEXPWM2_OUTEN   |= FLEXPWM_OUTEN_PWMA_EN(1 << 0);

  FLEXPWM2_MCTRL   |= FLEXPWM_MCTRL_LDOK(1 << 0);

  FLEXPWM2_MCTRL   |= FLEXPWM_MCTRL_RUN(1 << 0);

//FLEXPWM3_PWM1 MASTER

  uint32_t freq_kHz = 500;

  // Enable clock for FLEXPWM3 (CG9: bits 20-21)

  CCM_CCGR4 |= (3 << 20);

//enable clock for xbar1

  CCM_CCGR2 |= CCM_CCGR2_XBAR1(CCM_CCGR_ON);

  // VAL1 determines frequency

  uint32_t M = IPG_CLOCK_HZ / (freq_kHz * 1000);

  // Configure PWM3 SM1 as EXT_SYNC generator

  FLEXPWM3_MCTRL &= ~(FLEXPWM_MCTRL_RUN(1 << 1));

  FLEXPWM3_SM1CTRL2 = FLEXPWM_SMCTRL2_INDEP;

  FLEXPWM3_SM1CTRL = FLEXPWM_SMCTRL_PRSC(0) | FLEXPWM_SMCTRL_FULL;

  FLEXPWM3_SM1INIT = 0;

  FLEXPWM3_SM1VAL0 = 0;

  FLEXPWM3_SM1VAL1 = M;

  FLEXPWM3_SM1VAL2 = 0;

  FLEXPWM3_SM1VAL3 = M/2;

  FLEXPWM3_SM1VAL5 = M/2;

  // Enable OUT_TRIG1 on VAL1 match

  FLEXPWM3_SM1TCTRL = (uint16_t)(1 << 1); // OUT_TRIG_EN bit 1 = PWM_OUT_TRIG1 on VAL1 match

  // Route FLEXPWM3_SM1_OUT_TRIG1:XBAR1_IN48 → XBARA1_OUT_FLEXPWM2_PWM0_EXT_SYNC 44

  XBARA1_SEL22 &= 0xff00; //Clear the SEL44 fields

  XBARA1_SEL22 |= 48; ///

  FLEXPWM3_OUTEN |= FLEXPWM_OUTEN_PWMB_EN(1 << 1);

  FLEXPWM3_MCTRL |= FLEXPWM_MCTRL_LDOK(1 << 1);

  FLEXPWM3_MCTRL |= FLEXPWM_MCTRL_RUN(1 << 1);

[Motafared]

I found the problem

The submodules in all register names are 0 indexd submodule 0,1,2,3

But in the table of xbar inputs for output trigger they are 1 indexed

So if you are working with submodule 0 and you want to assign its output trigger to xbar1 you should choose

FLEXPWM1_PWM1_OUT_TRIG0 or

FLEXPWM1_PWM1_OUT_TRIG1

[EdwinHz]

Hi @Motafared,

I highly recommend you download MCUXpresso and try the pwm example codes we provide with the i.MX RT1060 SDK for more information on how to achieve this setup.