Hi Nordics!
I am using app_pwm.c file in SDK 8.1, and when I use it with softdevice(advertising or data transfer event), sometimes pwm signal is reversed.
I guess, reversed signal's reason is the BLE interrupt. Because this problem is not occurred, when I don't use softdevice ( advertising or data transfer event)
And I need your advice for overcome this problem.
These are my development environment.
SDK 8.1
SD 8.0
nRF51822 AA G0
custom board
Timer1- 2channels
Timer2-1 channel.
3 PWM channels - Red led, Green led, Blue led.
first, I used app_pwm library. (100Hz )
/* */
static void pwm_init(void)
{
ret_code_t err_code;
/* 2-channel PWM, 100Hz, output on LED pins. */
app_pwm_config_t pwm1_cfg = APP_PWM_DEFAULT_CONFIG_2CH(10000L, GPIO_LED_RED, GPIO_LED_GREEN);
app_pwm_config_t pwm2_cfg = APP_PWM_DEFAULT_CONFIG_1CH(10000L, GPIO_LED_BLUE);
/* Set the polarity of the channel. */
pwm1_cfg.pin_polarity[0] = APP_PWM_POLARITY_ACTIVE_HIGH;
pwm1_cfg.pin_polarity[1] = APP_PWM_POLARITY_ACTIVE_HIGH;
pwm2_cfg.pin_polarity[0] = APP_PWM_POLARITY_ACTIVE_HIGH;
/* Initialize and enable PWM. */
err_code = app_pwm_init(&PWM1,&pwm1_cfg,pwm_1_ready_callback);
APP_ERROR_CHECK(err_code);
err_code = app_pwm_init(&PWM2,&pwm2_cfg,pwm_2_ready_callback);
APP_ERROR_CHECK(err_code);
app_pwm_enable(&PWM1);
app_pwm_enable(&PWM2);
}
void pwm_1_ready_callback(uint32_t pwm_id)
{
pwm_1_ready_flag = true;
}
void pwm_2_ready_callback(uint32_t pwm_id)
{
pwm_2_ready_flag = true;
}
second, I set the pwm chanel duty by using below code.
(in this function, I didn't wait callback. I just keep trying until PWM is ready)
static void color_setting(uint8_t red, uint8_t green, uint8_t blue)
{
color_red=red;
color_green=green;
color_blue=blue;
pwm_1_ready_flag = false;
pwm_2_ready_flag = false;
/* Set the duty cycle - keep trying until PWM is ready... */
while (app_pwm_channel_duty_set(&PWM1, 0, (uint32_t)(sin_table[color_red]/2.55)) == NRF_ERROR_BUSY);
while (app_pwm_channel_duty_set(&PWM1, 1, (uint32_t)(sin_table[color_green]/2.55)) == NRF_ERROR_BUSY);
while (app_pwm_channel_duty_set(&PWM2, 0, (uint32_t)(sin_table[color_blue]/2.55)) == NRF_ERROR_BUSY);
/* ... or wait for callback. */
// while(!pwm_1_ready_flag);
}
sin_table's value is from 0 to 255. so I divided it by 2.55
And this color_setting function is called in app_timer call_back function.
my app timer's interval is 40ms.
In other words, PWM values is changed in every 40ms, and it repeat 0~100 value.
This "PWM signal reversed" issue is not appeared, when I don't use softDevice.
Is there any idea for avoiding this problem??
This problem is critical issue on my project.
Please help me.
Thanks.
