From a8bf3fd7e051fa1aa36350c3f83407a6b12d2b2b Mon Sep 17 00:00:00 2001
From: Philipp <interfisch@gmx.net>
Date: Sun, 11 Jun 2017 00:22:50 +0200
Subject: [PATCH] Move log10 for audio volume from nodered to arduino pro mini
 and fix scaling

---
 firmware_arduino_mini/firmware_arduino_mini.ino | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/firmware_arduino_mini/firmware_arduino_mini.ino b/firmware_arduino_mini/firmware_arduino_mini.ino
index aefcfcf..c921fe7 100644
--- a/firmware_arduino_mini/firmware_arduino_mini.ino
+++ b/firmware_arduino_mini/firmware_arduino_mini.ino
@@ -1,3 +1,4 @@
+#include <math.h>
 
 #define PIN_DATA_VOL_A   8
 #define PIN_DATA_VOL_B   7
@@ -106,6 +107,11 @@ void switchInputs(uint8_t channel, bool state) {
   
 }
 
+uint8_t logify(uint8_t volumelinear){
+  double volumelog=log10( ((double)volumelinear)/10.0 +1)*97;
+  return (int)volumelog;
+}
+
 // control a M62429 Chip for Volume Control
 // function take from here: http://forum.arduino.cc/index.php?topic=244152.0
 void setVolume(uint8_t volume, uint8_t dataPin) {
@@ -171,7 +177,7 @@ void loop() {
         }
         
         int vol=ser.substring(2).toInt();
-        setVolume(vol,datapin);
+        setVolume(logify(vol),datapin);
         
       } else if(command == 'r') { // relais