Hello,
Here's a patch against us428control in the latest alsa-tools that adds
the following enhancements:
- Master fader and Input Monitor faders use a logarithmic scale, like in Windows
- When the Master fader is all the way down, the sound stops instead
of just getting really quiet
- Input Monitor pan knob now requires 1 revolution instead of 10 to
pan from left to right, like in Windows
- LEDs are reset to a known state when us428control starts
- A new command line option "-g" to allow the gain sliders to go above
0dB gain, which may result in clipping
Mike Bourgeous
diff -u4 alsa-tools-1.0.14rc3/us428control/Cus428State.cc alsa-tools-1.0.14rc3-new/us428control/Cus428State.cc
--- alsa-tools-1.0.14rc3/us428control/Cus428State.cc 2007-02-26 02:24:15.000000000 -0700
+++ alsa-tools-1.0.14rc3-new/us428control/Cus428State.cc 2007-09-07 15:15:22.000000000 -0600
@@ -45,8 +45,11 @@
void Cus428State::InitDevice(void)
{
if (us428ctls_sharedmem->CtlSnapShotLast >= 0)
SliderChangedTo(eFaderM, ((unsigned char*)(us428ctls_sharedmem->CtlSnapShot + us428ctls_sharedmem->CtlSnapShotLast))[eFaderM]);
+
+ // Reset the LEDs to the state known by us428control
+ LightSend();
}
int Cus428State::LightSend()
{
@@ -349,9 +352,13 @@
while( index < 4 && (1 << index) != Light[0].Value)
index++;
if (index >= 4)
return;
- Volume[index].PanTo(Diff, us428_ctls->Knob(eK_SET));
+
+ // The pan encoder has 24 detents. A multiple of 13 allows
+ // the pan to go from full-left to full-right in 20 clicks
+ // instead of 255 clicks (over 10 full turns!).
+ Volume[index].PanTo(Diff * 13, us428_ctls->Knob(eK_SET));
if (!LightIs(eL_Mute0 + index))
SendVolume(Volume[index]);
return;
}
diff -u4 alsa-tools-1.0.14rc3/us428control/us428control.cc alsa-tools-1.0.14rc3-new/us428control/us428control.cc
--- alsa-tools-1.0.14rc3/us428control/us428control.cc 2007-02-26 02:24:15.000000000 -0700
+++ alsa-tools-1.0.14rc3-new/us428control/us428control.cc 2007-09-07 15:19:39.000000000 -0600
@@ -43,8 +43,10 @@
#define SND_CARDS 8
int verbose = 1;
+int positive_gain = 0;
+
Cus428Midi Midi;
static void error(const char *fmt, ...)
@@ -62,10 +64,11 @@
static void usage(void)
{
printf("Tascam US-428 Control\n");
printf("version %s\n", VERSION);
- printf("usage: "PROGNAME" [-v verbosity_level 0..2] [-c card] [-D device] [-u usb-device] [-m mode]\n");
+ printf("usage: "PROGNAME" [-v verbosity_level 0..3] [-c card] [-D device] [-u usb-device] [-m mode] [-g]\n");
printf("mode is one of (us224, us428, mixxx)\n");
+ printf("The -g option allows the Input Monitor and Master gains to go above 0dB\n");
}
/*
* check the name id of the given hwdep handle
*/
@@ -170,9 +173,9 @@
char *device_name = NULL,
*usb_device_name = getenv("DEVICE");
char name[64];
- while ((c = getopt(argc, argv, "c:D:u:v:m:")) != -1) {
+ while ((c = getopt(argc, argv, "c:D:u:v:m:g")) != -1) {
switch (c) {
case 'c':
card = atoi(optarg);
break;
@@ -194,8 +197,12 @@
else
if (!strcmp(optarg, "mixxx"))
mode = 1;
break;
+ case 'g':
+ // Allow positive gain on sliders (which may result in clipping)
+ positive_gain = 1;
+ break;
default:
usage();
return 1;
}
diff -u4 alsa-tools-1.0.14rc3/us428control/usbus428ctldefs.h alsa-tools-1.0.14rc3-new/us428control/usbus428ctldefs.h
--- alsa-tools-1.0.14rc3/us428control/usbus428ctldefs.h 2007-02-26 02:24:15.000000000 -0700
+++ alsa-tools-1.0.14rc3-new/us428control/usbus428ctldefs.h 2007-09-07 15:16:36.000000000 -0600
@@ -2,8 +2,10 @@
/*
*
* Copyright (c) 2003 by Karsten Wiese <annabellesgarden@xxxxxxxx>
*
+ * Logarithmic slider code (c) 2007 by Mike Bourgeous <nitrogen@xxxxxxxxxxxxxxxxxxxxx>
+ *
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
@@ -19,9 +21,12 @@
*/
#ifdef __cplusplus
#include <string.h>
+#include <math.h>
+#include <stdlib.h>
extern int verbose;
+extern int positive_gain;
#endif
enum E_In84 {
eFader0 = 0,
@@ -98,26 +103,94 @@
}
int Scale(){return 0x40;}
void calculate() {
- int lPan = (int)Pan * Slider / 0x80;
- int ValL = (Slider - lPan) * Scale();
- LH = ValL >> 8;
- LL = ValL;
- int ValR = (Slider + lPan) * Scale();
- RH = ValR >> 8;
- RL = ValR;
+ int Val;
+ int ScaledL, ScaledR;
+ float PanLeft, PanRight;
+ float Norm;
+ float dBL, dBR;
+
+ // Subtract 1 because the sliders usually don't reach 0 due to sampling inaccuracy
+ Val = (Slider - 1);
+
+ if(Val < 0) {
+ Val = 0;
+ }
+
+ // This is a balance knob-style pan law
+ PanLeft = (float)(Pan + 127) / 127.0;
+ PanRight = 2.0 - PanLeft;
+
+ if(PanLeft < 0.0) {
+ PanLeft = 0.0;
+ }
+ if(PanLeft > 1.0) {
+ PanLeft = 1.0;
+ }
+ if(PanRight < 0.0) {
+ PanRight = 0.0;
+ }
+ if(PanRight > 1.0) {
+ PanRight = 1.0;
+ }
+
+ Norm = (float)Val / 254.0;
+
+ if(positive_gain) {
+ // -55dB to +12dB
+ dBL = 67.0 * (Norm - 1.0) + 12.0;
+ dBR = 67.0 * (Norm - 1.0) + 12.0;
+ } else {
+ // -55dB to 0dB
+ dBL = 55.0 * (Norm - 1.0);
+ dBR = 55.0 * (Norm - 1.0);
+ }
+
+ // 16384 == 0dB (unity) gain
+ ScaledL = 16384.0 * pow(10.0, dBL / 20.0) * PanLeft;
+ ScaledR = 16384.0 * pow(10.0, dBR / 20.0) * PanRight;
+
+ // Make sure the sound stops completely when the slider is at the bottom
+ if(ScaledL < 30) {
+ ScaledL = 0;
+ }
+ if(ScaledR < 30) {
+ ScaledR = 0;
+ }
+
+ // Prevent overflow of the 16-bit gain value
+ if(positive_gain) {
+ if(ScaledL > 65535) {
+ ScaledL = 65535;
+ }
+ if(ScaledR > 65535) {
+ ScaledR = 65535;
+ }
+ } else {
+ if(ScaledL > 16384) {
+ ScaledL = 16384;
+ }
+ if(ScaledR > 16384) {
+ ScaledR = 16384;
+ }
+ }
+
+ LH = ScaledL >> 8;
+ LL = ScaledL;
+ RH = ScaledR >> 8;
+ RL = ScaledR;
if (2 < verbose)
- printf("S=% 3i, P=% 3i, lP=% 3i, VL=%05i, VR=%05i\n", (int)Slider, (int)Pan, (int)lPan, ValL, ValR);
+ printf("Slider=% 3i, Pan=% 4i, Val=% 3i, dBL=% 6.2f, dBR=% 6.2f, ScaledL=%05i, ScaledR=%05i\n", (int)Slider, (int)Pan, Val, dBL, dBR, ScaledL, ScaledR);
}
void SetTo(unsigned char _Channel, int RawValue){
Slider = RawValue;
Channel = eFaderM == _Channel ? 4 : _Channel;
calculate();
}
void PanTo(int RawValue, bool Grob) {
- int NewPan;
+ int NewPan = 0;
if (Grob) {
static int GrobVals[] = {-128, -64, 0, 64, 127};
int i = 4;
while (i >= 0 && GrobVals[i] > Pan)
@@ -134,10 +207,24 @@
} else {
NewPan = Pan + RawValue;
}
+
+ // Since the step is now 13, make sure 0 can still be reached
+ if (abs(NewPan) < 7) {
+ NewPan = 0;
+ }
+
+ // If we went past the limit, but we weren't at the limit, clamp to the limit
+ if (NewPan < -128 && Pan > -128)
+ NewPan = -128;
+ else if (NewPan > 127 && Pan < 127)
+ NewPan = 127;
+
+ // If we were already at the limit, then clamping didn't occur above, so ignore the new value
if (NewPan < -128 || NewPan > 127)
return;
+
Pan = NewPan;
calculate();
}
#endif
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