@@ -31,7 +31,7 @@ Program p;

 /* clang-format off */

 char ops[][4] = {

-	"BRK", "---", "LI1", "LIX", "IOR", "IOW", "LDR", "STR",

+	"BRK", "NOP", "LI1", "LIX", "IOR", "IOW", "LDR", "STR",

 	"JMP", "JSR", "RTI", "RTS", "---", "---", "---", "---",

 	"POP", "DUP", "SWP", "OVR", "ROT", "AND", "ORA", "ROL",

 	"ADD", "SUB", "MUL", "DIV", "EQU", "NEQ", "GTH", "LTH"

@@ -24,5 +24,5 @@ rm -f ./bin/emulator

 cc -std=c89 -DDEBUG -Wall -Wno-unknown-pragmas -Wpedantic -Wshadow -Wextra -Werror=implicit-int -Werror=incompatible-pointer-types -Werror=int-conversion -Wvla -g -Og -fsanitize=address -fsanitize=undefined uxn.c emulator.c -L/usr/local/lib -lSDL2 -o bin/emulator

 # run

-./bin/assembler examples/draw.usm bin/boot.rom

+./bin/assembler examples/test.usm bin/boot.rom

 ./bin/emulator bin/boot.rom

new file mode 100644

@@ -0,0 +1,44 @@

+( draw routines )

+

+:dev/r fff8 ( std read port )

+:dev/w fff9 ( std write port )

+

+;x_ 2 ;y_ 2 ;x0 2 ;y0 2 ;x1 2 ;y1 2 ;color 1

+

+|0100 @RESET

+

+	( set dev/write to screen ) 

+	,01 ,dev/w STR 

+	,01 ,color STR

+

+	( init positions )

+	,0020 ,x0 STR^ ,0018 ,y0 STR^

+	,0030 ,x1 STR^ ,0048 ,y1 STR^

+	,x0 LDR^ ,x_ STR^ ,y0 LDR^ ,y_ STR^

+

+	( draw control points )

+	,02 ,color STR

+	,x0 LDR^ ,y0 LDR^ ,putpixel JSR

+	,x1 LDR^ ,y1 LDR^ ,putpixel JSR

+

+	,redraw JSR

+

+BRK

+

+@redraw

+	,0000 IOW^

+	,0000 IOW^

+	,00 IOW

+	,01 IOW

+	RTS

+

+@putpixel 

+	IOW^ ( y short )

+	IOW^ ( x short )

+	,color LDR IOW  ( color byte )

+	,00 IOW  ( redraw byte )

+	RTS

+

+|c000 @FRAME BRK 

+|d000 @ERROR BRK 

+|FFFA .RESET .FRAME .ERROR

@@ -5,6 +5,9 @@

 |0100 @RESET 

+	,00 ,dev/w STR ( set dev/write to console ) 

+

+

 BRK

 |c000 @FRAME BRK

@@ -25,15 +25,15 @@ void   mempoke16(Memory *m, Uint16 a, Uint16 b) { mempoke8(m, a, b >> 8); mempok

 Uint16 mempeek16(Memory *m, Uint16 a) { return (mempeek8(m, a) << 8) + mempeek8(m, a + 1); }

 void   push8(St8 *s, Uint8 a) { s->dat[s->ptr++] = a; }

 Uint8  pop8(St8 *s) { return s->dat[--s->ptr]; }

-Uint8  peek8(St8 *s, Uint8 a) { return s->dat[s->ptr - a]; }

+Uint8  peek8(St8 *s, Uint8 a) { return s->dat[s->ptr - a - 1]; }

 void   push16(St8 *s, Uint16 a) { push8(s, a >> 8); push8(s, a); }

 Uint16 pop16(St8 *s) { return pop8(s) + (pop8(s) << 8); }

-Uint16 peek16(St8 *s, Uint8 a) { return (peek8(s, a) << 8) + peek8(s, a + 1); }

+Uint16 peek16(St8 *s, Uint8 a) { return peek8(s, a * 2) + (peek8(s, a * 2 + 1) << 8); }

 /* I/O */

 void op_brk(Uxn *u) { setflag(&u->status,FLAG_HALT, 1); }

 void op_li1(Uxn *u) { u->literal += 1; }

 void op_lix(Uxn *u) { u->literal += u->ram.dat[u->ram.ptr++]; }

-void op_nop(Uxn *u) { printf("NOP"); (void)u; }

+void op_nop(Uxn *u) { printf("%02x\n", pop8(&u->wst)); }

 void op_ior(Uxn *u) { Device *dev = &u->dev[mempeek8(&u->ram, u->devr)]; if(dev) push8(&u->wst, dev->read(dev, pop8(&u->wst))); }

 void op_iow(Uxn *u) { Uint8 a = pop8(&u->wst); Device *dev = &u->dev[mempeek8(&u->ram, u->devw)]; if(dev) dev->write(dev, a); }

 void op_ldr(Uxn *u) { Uint16 a = pop16(&u->wst); push8(&u->wst, mempeek8(&u->ram, a)); }

@@ -44,9 +44,9 @@ void op_jsr(Uxn *u) { push16(&u->rst, u->ram.ptr); u->ram.ptr = pop16(&u->wst);

 void op_rts(Uxn *u) { u->ram.ptr = pop16(&u->rst); }

 /* Stack */

 void op_pop(Uxn *u) { pop8(&u->wst); }

-void op_dup(Uxn *u) { push8(&u->wst, peek8(&u->wst, 1)); }

+void op_dup(Uxn *u) { push8(&u->wst, peek8(&u->wst, 0)); }

 void op_swp(Uxn *u) { Uint8 b = pop8(&u->wst), a = pop8(&u->wst); push8(&u->wst, b); push8(&u->wst, a); }

-void op_ovr(Uxn *u) { Uint8 a = peek8(&u->wst,2); push8(&u->wst, a); }

+void op_ovr(Uxn *u) { push8(&u->wst, peek8(&u->wst, 1)); }

 void op_rot(Uxn *u) { Uint8 c = pop8(&u->wst), b = pop8(&u->wst), a = pop8(&u->wst); push8(&u->wst, b); push8(&u->wst, c); push8(&u->wst, a); }

 void op_and(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, b & a); }

 void op_ora(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, b | a); }

@@ -61,15 +61,16 @@ void op_neq(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst,

 void op_gth(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, b > a); }

 void op_lth(Uxn *u) { Uint8 a = pop8(&u->wst), b = pop8(&u->wst); push8(&u->wst, b < a); }

 /* --- */

+void op_nop16(Uxn *u) { printf("%04x\n", pop16(&u->wst)); }

 void op_ior16(Uxn *u) { Uint8 a = pop8(&u->wst); Device *dev = &u->dev[mempeek8(&u->ram, u->devr)]; if(dev) push16(&u->wst, (dev->read(dev, a) << 8) + dev->read(dev, a + 1)); }

 void op_iow16(Uxn *u) { Uint8 a = pop8(&u->wst); Uint8 b = pop8(&u->wst); Device *dev = &u->dev[mempeek8(&u->ram, u->devw)]; if(dev) { dev->write(dev, b); dev->write(dev, a); } }

 void op_ldr16(Uxn *u) { Uint16 a = pop16(&u->wst); push16(&u->wst, mempeek16(&u->ram, a)); }

 void op_str16(Uxn *u) { Uint16 a = pop16(&u->wst); Uint16 b = pop16(&u->wst); mempoke16(&u->ram, a, b); }

 /* Stack(16-bits) */

 void op_pop16(Uxn *u) { pop16(&u->wst); }

-void op_dup16(Uxn *u) { push16(&u->wst, peek16(&u->wst, 2)); }

+void op_dup16(Uxn *u) { push16(&u->wst, peek16(&u->wst, 0)); }

 void op_swp16(Uxn *u) { Uint16 b = pop16(&u->wst), a = pop16(&u->wst); push16(&u->wst, b); push16(&u->wst, a); }

-void op_ovr16(Uxn *u) { Uint16 a = peek16(&u->wst, 4); push16(&u->wst, a); }

+void op_ovr16(Uxn *u) { push16(&u->wst, peek16(&u->wst, 1)); }

 void op_rot16(Uxn *u) { Uint16 c = pop16(&u->wst), b = pop16(&u->wst), a = pop16(&u->wst); push16(&u->wst, b); push16(&u->wst, c); push16(&u->wst, a); }

 void op_and16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push16(&u->wst, b & a); }

 void op_ora16(Uxn *u) { Uint16 a = pop16(&u->wst), b = pop16(&u->wst); push16(&u->wst, b | a); }

@@ -90,7 +91,7 @@ void (*ops[])(Uxn *u) = {

 	op_pop, op_dup, op_swp, op_ovr, op_rot, op_and, op_ora, op_rol,

 	op_add, op_sub, op_mul, op_div, op_equ, op_neq, op_gth, op_lth,

 	/* 16-bit */

-	op_brk, op_nop, op_li1, op_lix, op_ior16, op_iow16, op_ldr16, op_str16, 

+	op_brk, op_nop16, op_li1, op_lix, op_ior16, op_iow16, op_ldr16, op_str16, 

 	op_jmp, op_jsr, op_nop, op_rts, op_nop, op_nop, op_nop, op_nop, 

 	op_pop16, op_dup16, op_swp16, op_ovr16, op_rot16, op_and16, op_ora16, op_rol16,

 	op_add16, op_sub16, op_mul16, op_div16, op_equ16, op_neq16, op_gth16, op_lth16

@@ -99,7 +100,7 @@ void (*ops[])(Uxn *u) = {

 Uint8 opr[][2] = { 

 	{0,0}, {0,0}, {0,0}, {0,0}, {1,1}, {1,0}, {2,1}, {3,0},

 	{2,0}, {2,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0},

-	{1,0}, {1,2}, {2,2}, {3,3}, {3,3}, {2,1}, {2,1}, {2,1},

+	{1,0}, {1,2}, {2,2}, {2,3}, {3,3}, {2,1}, {2,1}, {2,1},

 	{2,1}, {2,1}, {2,1}, {2,1}, {2,1}, {2,1}, {2,1}, {2,1},

 	/* 16-bit */

 	{0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, /* TODO */