Hi all,
I'm working on a project, in which I need some RF data transmission and highly accurate PWM signals for my application. We have a board with CC1310 SOC with PWM output on one of the connectors. Unfortunately, the accuracy of the PWM signal from CC1310 is not uniform for various duty cycles from 1% to 100%. I've tested with multiple CC1310 boards and all of them are showing random variations on each duty cycle from 1% to 100% (please check the log files). I think CC1310 should not be having such kind issues (I'm assuming CC1310 is generating a Hardware-PWM). Therefore, can anyone help me with understanding the CC1310's internal architecture and working?, so that I can resolve this issue as early as possible.
Questions:
1. Need confirmation on whether the CC1310 is generating hardware or software PWM?
2. What is the lowest resolution of the CC1310 PWM'signal I can get?
3. I'm taking the signal directly from CC1310's PWM pin, do I need to use any signal conditioning circuitry?
Code and other details:
Controller: CC1310F128RGZR.
Libraries: Non-RTOS.
PWM driver: Ti PWM driver.
PWM Configuration:
1. Time period 10ms.
2. PWM Duty unit is microsecond.
void PWM_Set_Init(void)
{
/* Initialize the PWM driver. */
PWM_init();
/* Initialize the PWM parameters */
PWM_Params_init(&pwmParams);
pwmParams.idleLevel = PWM_IDLE_LOW; /* Output low when PWM is not running */
pwmParams.periodUnits = PWM_PERIOD_US;
pwmParams.periodValue = 10000;
pwmParams.dutyUnits = PWM_DUTY_US;
pwmParams.dutyValue = 0;
/* Open the PWM instance */
pwm_Handler = PWM_open(Board_PWM1, &pwmParams);
if (pwm_Handler == NULL)
{
//UART_write(uart,"\n\rPwmInitFail",13);
while (1);
}
PWM_start(pwm_Handler); /* start PWM with 0% duty cycle */
}
/*PWM SET FUNCTION */
void fnPWM_Set(uint8_t ucPWMPercent, uint8_t ucType)
{
uint16_t ui16MappedPwmVal = 0;
uint8_t ucCurrentDutyCycle = 0;
if(PERMANENT_TYPE == ucType)
{
ucDuty_Cycle = ucPWMPercent;
/* By this method the Lamp switches directly to the desired PWM value... */
if (ucPWMPercent == 0)
{
PWM_setDuty(pwm_Handler,0);
}
else if (ucPWMPercent % 2 != 0)
{
ui16MappedPwmVal = (ucPWMPercent * 100) - 30;
/*subtracting by 30 as we're getting 0.3 difference in "ODD Duty-Cycle" */
PWM_setDuty(pwm_Handler,ui16MappedPwmVal);
}
else
{
ui16MappedPwmVal = ucPWMPercent * 100;
PWM_setDuty(pwm_Handler,ui16MappedPwmVal);
}
}
/***************Different LAMP LOGS************************/
Ttotal.xlsx
