wip

boards/adafruit-clue/include/periph_conf.h

@@ -116,7 +116,7 @@ static const spi_conf_t spi_config[] = {
 /** @} */
 
 /**
- * @name    PDM configuration
+ * @brief    PDM configuration
  * @{
  */
 static const pdm_conf_t pdm_config = {

boards/feather-nrf52840-sense/include/periph_conf.h

@@ -86,7 +86,7 @@ static const i2c_conf_t i2c_config[] = {
 /** @} */
 
 /**
- * @name    PDM configuration
+ * @brief    PDM configuration
  * @{
  */
 static const pdm_conf_t pdm_config = {

cpu/nrf52/include/periph_cpu.h

@@ -116,7 +116,6 @@ void spi_twi_irq_register_i2c(NRF_TWIM_Type *bus,
                               spi_twi_irq_cb_t cb, void *arg);
 
 /**
-
  * @brief   Acquire the shared I2C/SPI peripheral in I2C mode
  *
  * @param   bus bus to acquire exclusive access on
@@ -147,15 +146,14 @@ void nrf5x_spi_acquire(NRF_SPIM_Type *bus, spi_twi_irq_cb_t cb, void *arg);
  * @param   bus bus to release exclusive access on
  */
 void nrf5x_spi_release(NRF_SPIM_Type *bus);
- 
+
  /**
  * @brief   Structure for PDM configuration data
  */
 typedef struct {
     uint8_t din_pin;         /**< DIN pin */
     uint8_t clk_pin;         /**< CLK pin */
 } pdm_conf_t;
-
 #ifdef __cplusplus
 }
 #endif

cpu/nrf52/periph/pdm.c

@@ -26,7 +26,7 @@
 #include "periph/gpio.h"
 #include "periph/pdm.h"
 
-#define ENABLE_DEBUG    (0)
+#define ENABLE_DEBUG 0
 #include "debug.h"
 
 /* The samples buffer is a double buffer */

dist/tools/pdm_check/README.md

@@ -0,0 +1,13 @@
+# PDM Testing Report
+
+## About
+This report outlines the testing process and results for a PDM implementation on a Feather nRF52840 Sense board to validate its functionality and performance.
+
+## Requirements
+To run the python script, you need to install some packages listed in `requirements.txt`.
+
+## Usage
+This repord provides insights into the testing and the corresponding results obtained:
+-Testing the PDM and visualizing the results in a chart.
+-Saving the output data as a wave format for Audacity.
+-Comparing the output signals from Python script and that from the Audacity.

dist/tools/pdm_check/requirements.txt

@@ -0,0 +1,3 @@
+matplotlib==3.8.3
+numpy==1.26.4
+pyserial==3.5

tests/periph_pdm/testing_pdm_conversion.py → dist/tools/pdm_check/testing_pdm_conversion.py

@@ -1,20 +1,15 @@
 import matplotlib.pyplot as plt
 import matplotlib.patches as mpatches
-import re
 import numpy as np
-import os
-import csv
 from itertools import groupby
 from operator import itemgetter
 import serial
-import struct
 import wave
-import time
 
 str1 = "Start of the new buffer".encode('ascii')
-str2= "End of the new buffer".encode('ascii')
+str2 = "End of the new buffer".encode('ascii')
 
-start_index_buf = 0    
+start_index_buf = 0
 stop_index_buf = 0
 start_found = False
 buffer_number = 0
@@ -27,7 +22,6 @@
 ser.writelines(["start\n".encode('ascii')])
 while start:
     line = ser.readline()
-    #print(line)
     value = line.strip()
     data[key] = value
     if line.find(str1) != -1:
@@ -41,7 +35,7 @@
             break
     key +=1
 
-print(start_index_buf)     
+print(start_index_buf)
 print(stop_index_buf)
 print(buffer_number)
 ser.close()
@@ -61,23 +55,23 @@
 samplerate = 16000
 length = 1
 
-# The left channel for 1 second.
+# The left channel for 1 second
 t = np.linspace(0, length, samplerate)
 left_channel = 0.5 * np.sin(2 * np.pi * 440.0 * t)
 
-# Noise on the right channel.
+# Noise on the right channel
 #right_channel = np.random.random(size=samplerate)
 left_channel = data_to_plot/np.max(np.abs(data_to_plot))
 audio = np.array([left_channel]).T
 
-# Convert to (little-endian) 16 bit integers.
+# Convert to (little-endian) 16 bit integers
 audio = (audio * (2 ** 15 - 1)).astype("<h")
 
 # Save the data as a wave format
-with wave.open("sound_new_buf.wav", "w") as f:
+with wave.open("sound.wav", "w") as f:
     # Mono Channel
     f.setnchannels(1)
-    # 2 bytes per sample.
+    # 2 bytes per sample
     f.setsampwidth(2)
     f.setframerate(samplerate)
     f.writeframes(audio.tobytes())

drivers/include/periph/pdm.h

@@ -77,7 +77,9 @@ typedef enum {
 #define PDM_BUF_SIZE        (128U)
 #endif
 
-// Define the new buffer size
+/**
+ * @brief   Define the new buffer size
+ */
 #define NEW_BUF_SIZE    (PDM_BUF_SIZE * 5 * 16 * 16)
 
 /**