From 2c16a0f7e769605a8af3c275f12889dd90c2ad23 Mon Sep 17 00:00:00 2001
From: Ross Owen <ross@xmos.com>
Date: Thu, 5 Nov 2015 15:28:45 +0000
Subject: [PATCH] Updated PDM Mic integration for latest version of
 lib_mic_array

---
 module_usb_audio/pdm_mics/pcm_pdm_mic.xc | 42 +++++++++++++-----------
 1 file changed, 22 insertions(+), 20 deletions(-)

diff --git a/module_usb_audio/pdm_mics/pcm_pdm_mic.xc b/module_usb_audio/pdm_mics/pcm_pdm_mic.xc
index 3f959b47..fdb2eea2 100644
--- a/module_usb_audio/pdm_mics/pcm_pdm_mic.xc
+++ b/module_usb_audio/pdm_mics/pcm_pdm_mic.xc
@@ -1,8 +1,9 @@
 
-#include "devicedefines.h"
 
 #if (NUM_PDM_MICS > 0)
 
+#include "devicedefines.h"
+
 /* This file includes an example integration of lib_array_mic into USB Audio */
 
 #include <platform.h>
@@ -17,6 +18,8 @@
 #include "fir_decimator.h"
 #include "mic_array.h"
 
+#define DF 1
+
 /* Hardware resources */
 in port p_pdm_clk                = PORT_PDM_CLK;
 in buffered port:32 p_pdm_mics   = PORT_PDM_DATA;
@@ -27,6 +30,9 @@ clock pdmclk                     = on tile[PDM_TILE]: XS1_CLKBLK_3;
 unsafe void user_pdm_process(frame_audio * unsafe audio, int output[]);
 void user_pdm_init();
 
+int data_0[4*COEFS_PER_PHASE*DF] = {0};
+int data_1[4*COEFS_PER_PHASE*DF] = {0};
+
 void pdm_process(streaming chanend c_ds_output_0, streaming chanend c_ds_output_1, chanend c_audio)
 {
     unsigned buffer = 1;     // Buffer index
@@ -36,6 +42,15 @@ void pdm_process(streaming chanend c_ds_output_0, streaming chanend c_ds_output_
 
     user_pdm_init();
 
+    unsigned decimation_factor=DF;
+    unsafe
+    {
+        decimator_config_common dcc = {FRAME_SIZE_LOG2, 1, 0, 0, decimation_factor, fir_coefs[decimation_factor], 0};
+        decimator_config dc0 = {&dcc, data_0, {0, 0, 0, 0}};
+        decimator_config dc1 = {&dcc, data_1, {0, 0, 0, 0}};
+        decimator_configure(c_ds_output_0, c_ds_output_1, dc0, dc1);
+    }
+
     decimator_init_audio_frame(c_ds_output_0, c_ds_output_1, buffer, audio);
 
     while(1)
@@ -54,10 +69,6 @@ void pdm_process(streaming chanend c_ds_output_0, streaming chanend c_ds_output_
     }
 }
 
-#define DF 1
-
-#define OUTPUT_SAMPLE_RATE (48000/DF)
-
 #if MAX_FREQ != 48000
 #error NOT CURRENTLY SUPPORTED
 #endif
@@ -65,10 +76,6 @@ void pdm_process(streaming chanend c_ds_output_0, streaming chanend c_ds_output_
 #error NOT CURRENTLY SUPPORTED
 #endif
 
-//TODO make these not global
-int data_0[4*COEFS_PER_PHASE*DF] = {0};
-int data_1[4*COEFS_PER_PHASE*DF] = {0};
-
 void pcm_pdm_mic(chanend c_pcm_out)
 {
     streaming chan c_multi_channel_pdm, c_sync, c_4x_pdm_mic_0, c_4x_pdm_mic_1;
@@ -80,18 +87,13 @@ void pcm_pdm_mic(chanend c_pcm_out)
     configure_in_port(p_pdm_mics, pdmclk);
     start_clock(pdmclk);
 
-    unsafe
-    {
-        decimator_config dc0 = {FRAME_SIZE_LOG2, 1, 0, 0, DF, FIR_LUT(DF), data_0, 0, {0,0, 0, 0}};
-        decimator_config dc1 = {FRAME_SIZE_LOG2, 1, 0, 0, DF, FIR_LUT(DF), data_1, 0, {0,0, 0, 0}};
 
-        par 
-        {
-            pdm_rx(p_pdm_mics, c_4x_pdm_mic_0, c_4x_pdm_mic_1);
-            decimate_to_pcm_4ch(c_4x_pdm_mic_0, c_ds_output_0, dc0);
-            decimate_to_pcm_4ch(c_4x_pdm_mic_1, c_ds_output_1, dc1);
-            pdm_process(c_ds_output_0, c_ds_output_1, c_pcm_out);
-        }
+    par 
+    {
+        pdm_rx(p_pdm_mics, c_4x_pdm_mic_0, c_4x_pdm_mic_1);
+        decimate_to_pcm_4ch(c_4x_pdm_mic_0, c_ds_output_0);
+        decimate_to_pcm_4ch(c_4x_pdm_mic_1, c_ds_output_1);
+        pdm_process(c_ds_output_0, c_ds_output_1, c_pcm_out);
     }
 }