Hi
I am working on interfacing PDM mic (Adafruit PDM MEMS Microphone) with nRF9160 DK, I used AT Client sample as a base code and I have added all rest code from the following ticket devzone.nordicsemi.com/.../pdm-working step by step and other related tickets. my project is successfully build but when i flashed it in nRF9160 DK I am getting repeated output in LTE link monitor as shown below in txt file. The output keep repeating information about SPM which I did not change anything in please find the attached code below. Thank you
/*
* Copyright (c) 2018 Nordic Semiconductor ASA
*
* SPDX-License-Identifier: LicenseRef-BSD-5-Clause-Nordic
*/
#include <zephyr.h>
#include <stdio.h>
#include <drivers/uart.h>
#include <string.h>
#include <nrfx_pdm.h>
#include <hal/nrf_gpio.h>
#include <nrf9160.h>
#define PDM_BUF_SIZE 3072 //length of buffer in 16 bit words
int16_t pdm_buf[PDM_BUF_SIZE];
/**@brief Recoverable BSD library error. */
void bsd_recoverable_error_handler(uint32_t err)
{
printk("bsdlib recoverable error: %u\n", err);
}
void nrfx_pdm_event_handler(nrfx_pdm_evt_t const *const p_evt)
{
if (p_evt->buffer_requested) {
nrfx_pdm_buffer_set(pdm_buf, PDM_BUF_SIZE);
}
if (p_evt->buffer_released != 0) {
printk("Out: %4x @ 0x%x\r\n %4x @ 0x%x\r\n",
(uint16_t)pdm_buf[0], &pdm_buf[0],
(uint16_t)pdm_buf[1], &pdm_buf[1]);
}
}
static void pdm_init(void)
{
nrfx_pdm_config_t pdm_config = NRFX_PDM_DEFAULT_CONFIG(
10, 11); /*configures CLK to pin 10 and Din to pin 11*/
nrfx_pdm_init(&pdm_config, nrfx_pdm_event_handler);
}
/*ISR workaround given by Nordic*/
ISR_DIRECT_DECLARE(pdm_isr_handler)
{
nrfx_pdm_irq_handler();
ISR_DIRECT_PM(); /* PM done after servicing interrupt for best latency
*/
return 1; /* We should check if scheduling decision should be made */
}
void main(void)
{
printk("The AT host sample started\n");
{
IRQ_DIRECT_CONNECT(PDM_IRQn, 0, pdm_isr_handler, 0); //workaround line
printk("Starting PDM program!\n");
printk("PDM Buffer size: %d in 16 bit words\n", PDM_BUF_SIZE);
/*
bool enabled = nrfx_pdm_enable_check();
printk(enabled ? "true/n" : "false\n");
*/
pdm_init();
printk("%4x is the starting address\n", &pdm_buf);
printk("%4x is current value at %x\n", pdm_buf[0], &pdm_buf);
printk("The PDM will start reading NOW...\n");
/* for (int i = 0; i < 500; i++) {
int k = 5;
for (volatile int j = 0; j < 50; j++) {
k = !k;
}
}*/
nrfx_pdm_start();
for (int i = 0; i < 100; i++) {
int k = 5;
for (volatile int j = 0; j < 100; j++) {
k = !k;
}
}
nrfx_pdm_stop();
printk("%4x is current value at %x\n", pdm_buf[0], &pdm_buf);
}
}
