How to restart a TCPWM and Counter for resue with different parameters?

[EmBa_4588821]

Hello,

I am using one PWM, one Delay and one Counter to implement two different functions. These are  1) Create a single pulse with a certain delay 2) Create a certain number of pulses again starting with a delay. Please find below how I configured the TCPWM's for that purpose.

Here are the two functions I use to get all running:

void SinglePulse(Mode_Parameter *mode_parameter)
{
    uint32_t compare1, pwm_period ;
    cy_stc_tcpwm_pwm_config_t *ptr = (cy_stc_tcpwm_pwm_config_t *) &Pulse_Gen_1_config;
    ptr->runMode = CY_TCPWM_PWM_ONESHOT;  //One Shot Configuration
    ptr->compare0 = 75000;
    ptr->period0 = 100000;
    Delay_Counter_1_Start();
    Delay_Counter_1_SetPeriod(400000);  
    Pulse_Gen_1_Start();
}

The second one is to generate a PWM for a certain number of pulses (controlled by the Counter_1)

void MultiPulse (Mode_Parameter *mode_parameter)
{
    uint32_t compare1, pwm_period ;
    cy_stc_tcpwm_pwm_config_t *ptr = (cy_stc_tcpwm_pwm_config_t *) &Pulse_Gen_1_config;
    ptr->runMode = CY_TCPWM_PWM_CONTINUOUS; //Continuous Run
    ptr->compare0 = 75000;
    ptr->period0 = 100000;
    Delay_Counter_1_Start();
    Delay_Counter_1_SetPeriod(0);
    Counter_1_Start(); //This is pretty much the only difference from the previous function
    Pulse_Gen_1_Start(); 
}

They seem to work fine the first time after boot. If you call the other one as second, the counter behaves like the previous configuration.

Scenario 1: (After reset)

1) Call the SinglePulse first. Single pulse achieved.

2) Call next the MultiPulse. I don't get multiple passes, one a single pass.

Scenario 2: (After reset)

1) Call the MultiplePulse first. I get the exact number of pulses I need and it it stops.

2) Call next the Single Pulse. I get the delay and the first pulse but then the pulse never stops. It just keeps coming.

I guess I need somehow to reinitialize the TCPWM's to get the effect of a board reset, but I could't do that.

Thanks in advance.

[MotooTanaka]

Hi,

Last time I played with PSoC6 PWM, I needed to call _TriggerStart() after _Enable() to restart a stopped PWM.

I wonder if calling

     Delay_Counter_1_TriggerStart()  ;

after

     Delay_Counter_1_SetPeriod(x) ;

helps or not.

moto

[EmBa_4588821]

Hello Moto,

Unfortuantely it didn't help. To be more clear, the problem is not restarting a stopped PWM. It is to change the run mode of the TCPWM from "continuous" to "one shot" or vice versa. Once the TCPWM starts in either mode, I cannot switch to the other one without resetting the board.

Thanks

[MotooTanaka]

Hi,

I'm sorry that I missed the point.

Then how about replacing

     Pulse_Gen_1_Start() ;

with

     Pulse_Gen_1_Init(&pulse_gen_1_config) ;

     Pulse_Gen_1_Enable() ;

Because, _Start() call Init() only once.

From the 2nd time, it calls only Enable() ;

moto

[MotooTanaka · Accepted solution]

Dear EmBa-san,

I hacked a little today.

Then I found that Pulse_Gen_config is defined as "const".

So when I assigned a value to ptr->runMode, the program jumped to exception handling.

Then I provided local variable of same type "pulse_gen_config" and tested with a minimum circuit

using CY8CKIT-062-BLE.

When I set break points at each CyDelay(1000) ;

After SinglePulse(), one time black to light

After MultiPulse() , LED blinks till the next SinglePulse() will be called.

schematic

pins

main.c

Note: In the "init_hardware()",

I copy Pulse_Gen_config to pulse_gen_config.

==================

#include "project.h"

cy_stc_tcpwm_pwm_config_t     pulse_gen_config ;

void init_hardware(void)

{

    __enable_irq(); /* Enable global interrupts. */

    pulse_gen_config = Pulse_Gen_config ;

}

void SinglePulse(void)

{

//    uint32_t compare1, pwm_period ;

    cy_stc_tcpwm_pwm_config_t *ptr = &pulse_gen_config ;

    Pulse_Gen_Disable() ;

    Pulse_Gen_DeInit() ;

    ptr->runMode = CY_TCPWM_PWM_ONESHOT ;

    ptr->compare0 = 5000 ;

    ptr->period0 = 10000 ;

    (void) Cy_TCPWM_PWM_Init(Pulse_Gen_HW, Pulse_Gen_CNT_NUM, ptr);

    Cy_TCPWM_Enable_Multiple(Pulse_Gen_HW, Pulse_Gen_CNT_MASK);

    #if (Pulse_Gen_INPUT_DISABLED == 7UL)

        Cy_TCPWM_TriggerStart(Pulse_Gen_HW, Pulse_Gen_CNT_MASK);

    #endif /* (Pulse_Gen_INPUT_DISABLED == 7UL) */  

}

void MultiPulse(void)

{

//    uint32_t compare1, pwm_period ;

    cy_stc_tcpwm_pwm_config_t *ptr = &pulse_gen_config ;

    Pulse_Gen_Disable() ;

    Pulse_Gen_DeInit() ;

    ptr->runMode = CY_TCPWM_PWM_CONTINUOUS ;

    ptr->compare0 = 5000 ;

    ptr->period0 = 10000 ;

    // Pulse_Gen_Init(ptr) ;

    (void) Cy_TCPWM_PWM_Init(Pulse_Gen_HW, Pulse_Gen_CNT_NUM, ptr);

    Cy_TCPWM_Enable_Multiple(Pulse_Gen_HW, Pulse_Gen_CNT_MASK);

    #if (Pulse_Gen_INPUT_DISABLED == 7UL)

        Cy_TCPWM_TriggerStart(Pulse_Gen_HW, Pulse_Gen_CNT_MASK);

    #endif /* (Pulse_Gen_INPUT_DISABLED == 7UL) */  

}

int main(void)

{

    init_hardware() ;

    /* Enable CM4.  CY_CORTEX_M4_APPL_ADDR must be updated if CM4 memory layout is changed. */

    //    Cy_SysEnableCM4(CY_CORTEX_M4_APPL_ADDR);

    /* Place your initialization/startup code here (e.g. MyInst_Start()) */

    for(;;)

    {

        SinglePulse() ;

        CyDelay(1000) ;

        MultiPulse() ;

        CyDelay(1000) ;

    }

}

==================

Best Regards,

8-Apr-2020

Motoo Tanaka