Hi I am using nRF connect 2.3.0 with VS Code on Windows 11. My board is a Custom board with nRF52832 QFAA.
I am trying to find a working example of PPI with SAADC collection. I found this and it has A LOT of what I want but doesnt actually work. There are several issues with it including the fact that it isnt using NRF Connect 2.x.x.
This is my sample code:
#include <inttypes.h>
#include <stddef.h>
#include <stdint.h>
#include <errno.h>
#include <time.h>
#include <zephyr/kernel.h>
#include <zephyr/logging/log.h>
#include <nrfx_saadc.h>
#include <nrfx_ppi.h>
#include <nrfx_timer.h>
#include <drivers/nrfx_errors.h>
#include <zephyr/drivers/gpio.h>
//This is set so battery power can be down to mins and still work
#define NRF_POWER_HAS_POFCON 0
#define LOG_MODULE_NAME drone_controller_main
LOG_MODULE_REGISTER(LOG_MODULE_NAME, LOG_LEVEL_DBG);
#if !DT_NODE_EXISTS(DT_PATH(zephyr_user)) || \
!DT_NODE_HAS_PROP(DT_PATH(zephyr_user), io_channels)
#error "No suitable devicetree overlay specified"
#endif
//SAADC Defines
// define the number of SAADC channels and parameters
#define SAADC_CHANNELS_IN_USE 4
#define SAADC_SAMPLE_INTERVAL_MS 100
#define SAADC_RESOLUTION NRF_SAADC_RESOLUTION_10BIT
#define SAADC_OVERSAMPLE NRF_SAADC_OVERSAMPLE_DISABLED
//define the buttons
#define SW0 DT_ALIAS(sw0)
#define SW1 DT_ALIAS(sw1)
#define SW2 DT_ALIAS(sw2)
#define SW3 DT_ALIAS(sw3)
#define SW4 DT_ALIAS(sw4)
#define SW5 DT_ALIAS(sw5)
#define SW6 DT_ALIAS(sw6)
#define SW7 DT_ALIAS(sw7)
#define SW8 DT_ALIAS(sw8)
//Devicetree node for the var resistor power
#define PWRR_NODE DT_ALIAS(pwrr)
#define PWRL_NODE DT_ALIAS(pwrl)
//Power the joysticks
#define PWRR DT_ALIAS(pwrr)
#define PWRL DT_ALIAS(pwrl)
//setup the LED's
#define LED0_R DT_ALIAS(led0)
#define LED3_G DT_ALIAS(led3)
#define LED4_B DT_ALIAS(led4)
//Timer settings
#define TIMER_INTERVAL_MS 1000
#define NRFX_SAADC_CHANNEL_COUNT 4
#define SAADC_BUF_SIZE NRFX_SAADC_CHANNEL_COUNT
#define SAADC_BUF_COUNT 2
static nrfx_timer_t timer1 = NRFX_TIMER_INSTANCE(1); //timer instance
static nrf_saadc_value_t samples[SAADC_BUF_COUNT][SAADC_BUF_SIZE]; //sample buffer
static nrf_ppi_channel_t m_timer_saadc_ppi_channel; //timer to ppi channel
static const uint32_t saadc_sampling_rate = 250; // milliseconds (ms)
static const nrf_saadc_input_t ANALOG_INPUT_MAP[NRFX_SAADC_CHANNEL_COUNT] = {NRF_SAADC_INPUT_AIN0, NRF_SAADC_INPUT_AIN1, NRF_SAADC_INPUT_AIN4, NRF_SAADC_INPUT_AIN5};
static void timer_event_handler(nrf_timer_event_t event_type, void *p_context)
{
printk("Event");
}
// Simple function to provide an index to the next input buffer
// Will simply alernate between 0 and 1 when SAADC_BUF_COUNT is 2
static uint32_t next_free_buf_index(void)
{
static uint32_t buffer_index = -1;
buffer_index = (buffer_index + 1) % SAADC_BUF_COUNT;
return buffer_index;
}
static void ppi_init(void)
{
nrfx_err_t err;
// Trigger task sample from timer
err = nrfx_ppi_channel_alloc(&m_timer_saadc_ppi_channel);
if(err==NRFX_SUCCESS)
LOG_DBG("ppi alloc success");
err = nrfx_ppi_channel_assign(m_timer_saadc_ppi_channel,
nrfx_timer_event_address_get(&timer1, NRF_TIMER_EVENT_COMPARE0),
nrf_saadc_task_address_get(NRF_SAADC,NRF_SAADC_TASK_SAMPLE));
err = nrfx_ppi_channel_enable(m_timer_saadc_ppi_channel);
if(err==NRFX_SUCCESS)
LOG_DBG("PPI enable ok");
}
static void timer_init(void)
{
nrfx_timer_config_t timer_cfg = NRFX_TIMER_DEFAULT_CONFIG;
timer_cfg.frequency = NRF_TIMER_FREQ_31250Hz;
nrfx_timer_init(&timer1, &timer_cfg, timer_event_handler);
nrfx_timer_extended_compare(&timer1,NRF_TIMER_CC_CHANNEL0,nrfx_timer_ms_to_ticks(&timer1, saadc_sampling_rate),NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,false);
nrfx_timer_resume(&timer1);
}
/*
* Function: saadc_handler
* Description: This handler is called when there is SAADC data available
* when the data is processed, saadc is re-enabled for more data.
* Data is sent to the calibrate routine until the drone is ready
* then the data is formatted for the joystick.
*/
static void saadc_handler(nrfx_saadc_evt_t const * p_event)
{
uint16_t samples_number;
uint16_t flydata[4];
nrfx_err_t err;
switch (p_event->type)
{
case NRFX_SAADC_EVT_DONE:
samples_number = p_event->data.done.size;
for (uint16_t i = 0; i < samples_number; i++)
{
LOG_DBG("SAADC_Value: Channel[%d] - %d",i,p_event->data.done.p_buffer[i]);
//flydata[i]=p_event->data.done.p_buffer[i];
}
break;
case NRFX_SAADC_EVT_BUF_REQ:
err = nrfx_saadc_buffer_set(&samples[next_free_buf_index()][0], SAADC_BUF_SIZE);
break;
default:
LOG_DBG("SAADC evt %d", p_event->type);
break;
}
}
static void saadc_configure(void)
{
nrfx_err_t err;
uint8_t channel_mask = 0;
static nrfx_saadc_channel_t channel_configs[NRFX_SAADC_CHANNEL_COUNT];
nrfx_saadc_adv_config_t saadc_adv_config = NRFX_SAADC_DEFAULT_ADV_CONFIG;
//Update the timer and start for the adv config
saadc_adv_config.internal_timer_cc = 0;
saadc_adv_config.start_on_end = true;
err = nrfx_saadc_init(NRFX_SAADC_DEFAULT_CONFIG_IRQ_PRIORITY);
if(err!=NRFX_SUCCESS)
LOG_INF("Error: SAADC init failed");
for(int i=0;i<NRFX_SAADC_CHANNEL_COUNT;i++)
{
nrf_saadc_input_t pin = ANALOG_INPUT_MAP[i];
nrfx_saadc_channel_t config = NRFX_SAADC_DEFAULT_CHANNEL_SE(pin, i);
// Replace some parameters in default config
config.channel_config.reference = NRF_SAADC_REFERENCE_INTERNAL;
config.channel_config.gain = NRF_SAADC_GAIN1_4;
// Copy to list of channel configs
memcpy(&channel_configs[i], &config, sizeof(config));
// Update channel mask
channel_mask |= 1 << i;
}
err = nrfx_saadc_channels_config(channel_configs, NRFX_SAADC_CHANNEL_COUNT);
err = nrfx_saadc_advanced_mode_set(channel_mask, NRF_SAADC_RESOLUTION_10BIT, &saadc_adv_config, saadc_handler);
// Configure two buffers to ensure double buffering of samples, to avoid data loss when the sampling frequency is high
err = nrfx_saadc_buffer_set(&samples[next_free_buf_index()][0], SAADC_BUF_SIZE);
err = nrfx_saadc_mode_trigger();
}
void main(void)
{
printk("Hello World! %s\n", CONFIG_BOARD);
LOG_DBG("LOG DBG test");
timer_init();
ppi_init();
saadc_configure();
while(1)
{
__WFE();
}
}
This is the conf file:
#required for the custom board CONFIG_CLOCK_CONTROL_NRF_K32SRC_XTAL=n CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y #memory settings CONFIG_HEAP_MEM_POOL_SIZE=16384 CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=2304 CONFIG_MAIN_STACK_SIZE=2048 #Thread settings CONFIG_THREAD_NAME=y CONFIG_THREAD_MONITOR=y #GPIO and ADC settings CONFIG_GPIO=y CONFIG_NRFX_SAADC=y CONFIG_NRFX_PPI=y CONFIG_NRFX_TIMER1=y #Enable statistics (MCU ADDED) CONFIG_STATS=y CONFIG_STATS_NAMES=y #MCU Manager CONFIG_MCUMGR=y CONFIG_MCUMGR_CMD_IMG_MGMT=y CONFIG_MCUMGR_CMD_OS_MGMT=y CONFIG_BOOTLOADER_MCUBOOT=y # Support for taskstat command CONFIG_OS_MGMT_TASKSTAT=y #Logging CONFIG_CONSOLE=y CONFIG_LOG_BACKEND_RTT=y CONFIG_LOG_DEFAULT_LEVEL=4 CONFIG_USE_SEGGER_RTT=y CONFIG_RTT_CONSOLE=y CONFIG_PRINTK=y CONFIG_LOG_PRINTK=y CONFIG_CBPRINTF_FP_SUPPORT=y CONFIG_LOG=y CONFIG_LOG_MODE_IMMEDIATE=y
My problem is that NO sample is ever printed in the event handler and it is not even called. What happens when I run it without stepping through is a fault:
[00:00:00.002,532] <err> os: >>> ZEPHYR FATAL ERROR 1: Unhandled interrupt on CPU 0
[00:00:00.003,112] <err> os: Current thread: 0x20000368 (main)
[00:00:00.008,575] <err> fatal_error: Resetting system
I am very new to this and am trying to get samples first. Please let me know if you see anything I missed or more likely didn't configure correctly. If there is a PPI SAADC example somewhere I could look at that would help. I have looked at the PPI Trace example and it doesn't seem to apply.
Thanks
