INI option to enable volume control.

MiSTer.ini

@@ -6,7 +6,9 @@ composite_sync=0       ; set to 1 for composite sync on HSync signal of VGA outp
 vga_scaler=0           ; set to 1 to connect VGA to scaler output.
 hdmi_audio_96k=0       ; set to 1 for 96khz/16bit HDMI audio (48khz/16bit otherwise)
 keyrah_mode=0x18d80002 ; VIDPID of keyrah for special code translation (0x23418037 for Arduino Micro)
+volumectl=1            ; enable audio volume control by multimedia keys
 ;bootscreen=0          ; uncomment to disable boot screen of some cores like Minimig. 
+;mouse_throttle=10     ; 1-100 mouse speed divisor. Useful for very sensitive mouses
 
 ; USER button emulation by keybaord. Usually it's reset button.
 ; 0 - lctrl+lalt+ralt (lctrl+lgui+rgui on keyrah)

cfg.cpp

@@ -39,6 +39,7 @@ const ini_var_t ini_vars[] = {
 	{ "KBD_NOMOUSE", (void*)(&(cfg.kbd_nomouse)), UINT8, 0, 1, 1 },
 	{ "MOUSE_THROTTLE", (void*)(&(cfg.mouse_throttle)), UINT8, 1, 100, 1 },
 	{ "BOOTSCREEN", (void*)(&(cfg.bootscreen)), UINT8, 0, 1, 1 },
+	{ "VOLUMECTL", (void*)(&(cfg.volumectl)), UINT8, 0, 1, 1 },
 };
 
 // mist ini config

cfg.h

@@ -28,6 +28,7 @@ typedef struct {
 	uint8_t kbd_nomouse;
 	uint8_t mouse_throttle;
 	uint8_t bootscreen;
+	uint8_t volumectl;
 	char video_conf[1024];
 } cfg_t;
 

user_io.cpp

@@ -424,6 +424,7 @@ void user_io_init(const char *path)
 	parse_video_mode();
 	FileLoadConfig("Volume.dat", &vol_att, 1);
 	vol_att &= 0x1F;
+	if (!cfg.volumectl) vol_att = 0;
 	spi_uio_cmd8(UIO_AUDVOL, vol_att);
 	user_io_send_buttons(1);
 
@@ -1896,6 +1897,8 @@ void user_io_osd_key_enable(char on)
 
 static void set_volume(int cmd)
 {
+	if (!cfg.volumectl) return;
+
 	vol_set_timeout = GetTimer(1000);
 
 	vol_att &= 0x17;