Fixed issue with midi

build.sh

@@ -34,7 +34,7 @@ else
 fi
 
 echo "Assembling.."
-./bin/assembler projects/demos/life.usm bin/boot.rom
+./bin/assembler projects/demos/drum-rack.usm bin/boot.rom
 
 echo "Running.."
 if [ "${2}" = '--cli' ]; 

projects/demos/mandelbrot.usm

@@ -0,0 +1,123 @@
+( a blank file )
+
+%+  { ADD } %-   { SUB }  %*  { MUL } %/   { DIV }  
+%<  { LTH } %>   { GTH }  %=  { EQU } %!   { NEQ } 
+%++ { ADD2 } %-- { SUB2 } %** { MUL2 } %// { DIV2 } 
+%<< { LTH2 } %>> { GTH2 } %== { EQU2 } %!! { NEQ2 }  
+
+( fixed-point )
+
+%RESF { #0008 }
+%TO2F { RESF #0040 SFT2 SFT2 }
+%MUL2F { MUL2 RESF SFT2 }
+%DIV2F { SWP2 TO2F SWP2 DIV2 }
+
+%RTN  { JMP2r }
+%TOB { SWP POP }
+%MOD2 { OVR2 OVR2 DIV2 MUL2 SUB2 }
+%MOD  { DUP2 / * - }
+%SFL2 { #0040 SFT2 SFT2 }
+
+%DEBUG  { .Console/byte DEO #0a .Console/char DEO }
+%DEBUG2 { .Console/short DEO2 #0a .Console/char DEO }
+
+%WIDTH { #0080 }
+%HEIGHT { #0080 }
+
+( devices )
+
+|00 @System     [ &vector $2 &wst      $1 &rst    $1 &pad   $4 &r      $2 &g     $2 &b      $2 ]
+|10 @Console    [ &pad    $8 &char     $1 &byte   $1 &short $2 &string $2 ]
+|20 @Screen     [ &vector $2 &width    $2 &height $2 &pad   $2 &x      $2 &y      $2 &addr  $2 &color $1 ]
+|30 @Audio0     [ &vector $2 &position $2 &output $1 &pad   $3 &adsr   $2 &length $2 &addr  $2 &volume $1 &pitch $1 ]
+|40 @Audio1     [ &vector $2 &position $2 &output $1 &pad   $3 &adsr   $2 &length $2 &addr  $2 &volume $1 &pitch $1 ]
+|50 @Audio2     [ &vector $2 &position $2 &output $1 &pad   $3 &adsr   $2 &length $2 &addr  $2 &volume $1 &pitch $1 ]
+|60 @Audio3     [ &vector $2 &position $2 &output $1 &pad   $3 &adsr   $2 &length $2 &addr  $2 &volume $1 &pitch $1 ]
+|70 @Midi       [ &vector $2 &channel  $1 &note   $1 &velocity $1 ]
+|80 @Controller [ &vector $2 &button   $1 &key    $1 ]
+|90 @Mouse      [ &vector $2 &x        $2 &y      $2 &state $1 &chord $1 ]
+|a0 @File       [ &vector $2 &success  $2 &offset $2 &pad   $2 &name  $2 &length $2 &load $2 &save $2 ]
+|b0 @DateTime   [ &year   $2 &month    $1 &day    $1 &hour $1 &minute $1 &second $1 &dotw $1 &doty $2 &isdst $1 ]
+
+( variables )
+
+|0000
+
+@zoom $1
+@iter $1
+@fractal [ &c_re $2 &c_im $2 &x $2 &y $2 ]
+
+( program )
+
+|0100 ( -> )
+
+	( theme ) 
+	#f840 .System/r DEO2 
+	#f840 .System/g DEO2 
+	#f840 .System/b DEO2
+
+	#20 .iter POK
+	#04 .zoom POK
+
+	#0000 #0080
+	&ver
+		( col ) OVR2 .Screen/y DEO2
+		#0000 #0080
+		&hor
+			( row ) OVR2 .Screen/x DEO2 
+			,mandelbrot JSR
+			( incr ) SWP2 #0001 ++ SWP2
+			OVR2 OVR2 LTH2 ,&hor JNZ
+		POP2 POP2
+		( incr ) SWP2 #0001 ++ SWP2
+		OVR2 OVR2 LTH2 ,&ver JNZ
+	POP2 POP2
+
+BRK
+
+@mandelbrot ( -- )
+	(
+		.Screen/x DEI2 
+		.Screen/y DEI2 )
+
+(
+		double c_re = [col - width/2.0]*4.0/width;
+        double c_im = [row - height/2.0]*4.0/width;
+        double x = 0, y = 0;
+        int iteration = 0;
+        while [x*x+y*y <= 4 && iteration < max] {
+            double x_new = x*x - y*y + c_re;
+            y = 2*x*y + c_im;
+            x = x_new;
+            iteration++;
+        }
+        if [iteration < max] putpixel[col, row, white];
+        else putpixel[col, row, black];
+)
+		
+	( c_re = [col - width / 2.0] * 4.0 / width )
+
+	( 
+
+	.Screen/x DEI2 TO2F
+	WIDTH TO2F
+	#0002 TO2F
+	DIV2F
+	SUB2
+
+	#0002 TO2F
+	WIDTH TO2F 
+	DIV2F
+
+	MUL2F
+
+	.fractal/c_re POK2
+
+)
+
+
+
+	#01 .Screen/color DEO
+
+
+RTN 

src/mpu.c

@@ -23,11 +23,19 @@ initmpu(Mpu *m, Uint8 device)
 			Pm_GetDeviceInfo(i)->name,
 			i == device ? "[x]" : "[ ]");
 	Pm_OpenInput(&m->midi, device, NULL, 128, 0, NULL);
+	m->queue = 0;
+	m->error = pmNoError;
 	return 1;
 }
 
 void
 listenmpu(Mpu *m)
 {
-	m->queue = Pm_Read(m->midi, m->events, 32);
+	const int result = Pm_Read(m->midi, m->events, 32);
+	if(result < 0) {
+		m->error = (PmError)result;
+		m->queue = 0;
+		return;
+	}
+	m->queue = result;
 }

src/mpu.h

@@ -20,6 +20,7 @@ typedef struct {
 	Uint8 queue;
 	PmStream *midi;
 	PmEvent events[32];
+	PmError error;
 } Mpu;
 
 int initmpu(Mpu *m, Uint8 device);

src/uxn.c

@@ -99,7 +99,7 @@ void op_div16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->s
 void op_and16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b & a); }
 void op_ora16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b | a); }
 void op_eor16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b ^ a); }
-void op_sft16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b >> (a & 0x000f) << ((a & 0x00f0) >> 4)); }
+void op_sft16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b >> (a & 0x0007) << ((a & 0x0070) >> 4)); }
 
 void (*ops[])(Uxn *u) = {
 	op_brk, op_lit, op_nop, op_pop, op_dup, op_swp, op_ovr, op_rot,