From d3abffa13dbbc26f3d3fc5e22abe11089b403381 Mon Sep 17 00:00:00 2001
From: Killorin <askillorin@wpi.edu>
Date: Thu, 17 Apr 2025 12:53:51 -0400
Subject: [PATCH] fix fft

cast in high priority task was causing data issues + buffer overflow causing crazy issues
---
 main.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/main.c b/main.c
index 79ecb6b..4297527 100644
--- a/main.c
+++ b/main.c
@@ -187,10 +187,9 @@ void capture_waveform(UArg arg1, UArg arg2)
 
         if (true) {
             adc_current_index = gADCBufferIndex;
+            int32_t j = 0;
             for(i=adc_current_index-FFT_BUF_LEN; i<adc_current_index; i++) {
-                //in[i].r = sinf(20*PI*i/FFT_BUF_LEN);
-                in[i].r = (float) gADCBuffer[ADC_BUFFER_WRAP(adc_current_index + i)];
-                in[i].i = 0;
+                adc_buffer_fft_sample[j++] = gADCBuffer[ADC_BUFFER_WRAP(adc_current_index + i)];
             }
         } else {
             // single read of options is atomic
@@ -231,7 +230,9 @@ void process_waveform(UArg arg1, UArg arg2) {
 
         if(true) { // fft
             for(i=0; i<FFT_BUF_LEN; i++) {
-                in[i].r *= w[i];
+                //in[i].r = sinf(20*PI*i/FFT_BUF_LEN);
+                in[i].r = (float) adc_buffer_fft_sample[i] * w[i];
+                in[i].i = 0;
             }
 
             kiss_fft(cfg, in, out);
@@ -240,7 +241,7 @@ void process_waveform(UArg arg1, UArg arg2) {
                 #define DB(out) 10 * log10f(out.r * out.r + out.i * out.i)
 
                 //adc_buffer_processed[i] = CONSTRAIN(HEIGHT- (int)roundf(0.5 * DB(out[i])));
-                adc_buffer_processed[i] = CONSTRAIN(HEIGHT- (int) (DB(out[i])) + 64);
+                adc_buffer_processed[i] = CONSTRAIN(HEIGHT- (int) (DB(out[i])) );
 
             }