nRF51822 PWM and GPIOTE: differrences between Keil MDK(ARMCC) and GNU_GCC_ARM Compiler

[robotden]

Hello everybody!

I have a problem with compilers for nRF51822. My problems: I create a pwm signal ~38Khz, duty 30% at pin 30 of nRF51822. This process is work well. I want use the function:

nrf_drv_gpiote_out_task_enable(pin)
nrf_drv_gpiote_out_task_disable(pin)

to Enable and Disable pwm signal to GPIO (pin 30). With Keil MDK is good (as the followd picture), but with gcc compiler is not good (as the second picture). I use SDK11, pwm_library example

Source code:

APP_PWM_INSTANCE(PWM1,1);                   // Create the instance "PWM1" using TIMER1.

static volatile bool ready_flag;            // A flag indicating PWM status.

void pwm_ready_callback(uint32_t pwm_id)    // PWM callback function
{
    ready_flag = true;
}

#define enable_pwm_out(pin)			nrf_drv_gpiote_out_task_enable(pin)
#define disable_pwm_out(pin)		nrf_drv_gpiote_out_task_disable(pin)
int main(void)
{
    ret_code_t err_code;
    
	
	/*2 channels PWM, 38,4Khz - 26us, p30 and p8*/
    app_pwm_config_t pwm1_cfg = APP_PWM_DEFAULT_CONFIG_2CH(26L, 30, 8);
    
    /* Switch the polarity of the second channel. */
		pwm1_cfg.pin_polarity[0] = APP_PWM_POLARITY_ACTIVE_HIGH;
    pwm1_cfg.pin_polarity[1] = APP_PWM_POLARITY_ACTIVE_HIGH;
    
    /* Initialize and enable PWM. */
    err_code = app_pwm_init(&PWM1,&pwm1_cfg,pwm_ready_callback);
    APP_ERROR_CHECK(err_code);
    app_pwm_enable(&PWM1);
    
    
    while(true)
    {
			
				disable_pwm_out(30);
				while (app_pwm_channel_duty_set(&PWM1, 0, 30) == NRF_ERROR_BUSY);
				//while (app_pwm_channel_duty_set(&PWM1, 1, 70) == NRF_ERROR_BUSY);
				
				//Create timing
				while(1){
					
					enable_pwm_out(30);	
					nrf_delay_us(2400);
					
					disable_pwm_out(30);
					nrf_delay_us(600);
					
					enable_pwm_out(30);	
					nrf_delay_us(1200);
					
					disable_pwm_out(30);
					nrf_delay_us(600);
					
					enable_pwm_out(30);	
					nrf_delay_us(600);
					
					disable_pwm_out(30);	
					nrf_delay_us(600);
				}
    }
    
}

Results with Keil MDK:

Results with ARM_GCC:

I do not understand why gcc_arm compiler is not good with my problems. Thanks for your watching!

[robotden]

The followed code is a part of Makefile:

#flags common to all targets
CFLAGS  = -DNRF51
CFLAGS += -DBOARD_PCA10028
CFLAGS += -DBSP_DEFINES_ONLY
CFLAGS += -mcpu=cortex-m0
CFLAGS += -mthumb -mabi=aapcs --std=gnu99
CFLAGS += -Wall -Werror -O3 -g3
CFLAGS += -mfloat-abi=soft
# keep every function in separate section. This will allow linker to dump unused functions
CFLAGS += -ffunction-sections -fdata-sections -fno-strict-aliasing
CFLAGS += -fno-builtin --short-enums 
# keep every function in separate section. This will allow linker to dump unused functions
LDFLAGS += -Xlinker -Map=$(LISTING_DIRECTORY)/$(OUTPUT_FILENAME).map
LDFLAGS += -mthumb -mabi=aapcs -L $(TEMPLATE_PATH) -T$(LINKER_SCRIPT)
LDFLAGS += -mcpu=cortex-m0
# let linker to dump unused sections
LDFLAGS += -Wl,--gc-sections
# use newlib in nano version
LDFLAGS += --specs=nano.specs -lc -lnosys

# Assembler flags
ASMFLAGS += -x assembler-with-cpp
ASMFLAGS += -DNRF51
ASMFLAGS += -DBOARD_PCA10028
ASMFLAGS += -DBSP_DEFINES_ONLY