@@ -10,13 +10,27 @@ cc uxn.c -std=c89 -Os -DNDEBUG -g0 -s -Wall -Wno-unknown-pragmas -o uxn

 ## Assembly Syntax

-- `;variable`, a named address(zero-page)

-- `:label`, a named address

-- `.pointer`, a pointer to a label

-- `@0010`, a position in the program

+### Write

+

+- `;variable`, set a name to address on the zero-page

+- `:label`, set a name to an address

+

+### Read

+

+- `,literal`, get a literal pointer

+- `.pointer`, get a raw pointer

+

+### Special

+

+- `@0010`, move to position in the program

+- `( comment )`

 ```

-< conditionals >

+( comment )

+

+;variable1

+;variable2

+;variable3

 .there ( 0a 05 GTH ) JMC

@@ -1,13 +1,3 @@

-< conditionals >

+( comment )

-.there ( 0a 05 GTH ) JMC

-

-:here

-	< when not equal >

-	ee

-	BRK

-

-:there

-	< when is equal >

-	ff

-	BRK

+,abcd ,ef STR

\ No newline at end of file

new file mode 100644

@@ -0,0 +1,11 @@

+< vectors >

+

+:RESET BRK

+:FRAME BRK

+:ERROR BRK

+

+@FFFA < vectors >

+

+.RESET

+.FRAME

+.ERROR

\ No newline at end of file

@@ -74,6 +74,13 @@ echo(Stack *s, Uint8 len, char *name)

 void wspush(Uint8 v) { cpu.wst.dat[cpu.wst.ptr++] = v; }

 Uint8 wspop(void) { return cpu.wst.dat[--cpu.wst.ptr]; }

+Uint16 wspop16(void) { 

+

+	Uint8 a = cpu.wst.dat[--cpu.wst.ptr];

+	Uint8 b = cpu.wst.dat[--cpu.wst.ptr];

+	return a + (b << 8); 

+

+}

 Uint8 wspeek(void) { return cpu.wst.dat[cpu.wst.ptr - 1]; }

 void rspush(Uint8 v) { cpu.rst.dat[cpu.rst.ptr++] = v; }

 Uint8 rspop(void) { return cpu.rst.dat[--cpu.rst.ptr]; }

@@ -102,17 +109,27 @@ void op_add() { wspush(wspop() + wspop()); }

 void op_sub() { wspush(wspop() - wspop()); }

 void op_mul() { wspush(wspop() * wspop()); }

 void op_div() { wspush(wspop() / wspop()); }

+void op_ldr() {  }

+void op_str() { 

+

+	Uint8 b = wspop();

+	Uint16 addr = wspop16();

+	printf("store: %02x @ %04x\n", b, addr);

+}

 void (*ops[])(void) = {

 	op_brk, op_rts, op_lit, op_drp, op_dup, op_swp, op_ovr, op_rot, 

 	op_jmu, op_jsu, op_jmc, op_jsc, op_equ, op_neq, op_gth, op_lth, 

-	op_and, op_ora, op_rol, op_ror, op_add, op_sub, op_mul, op_div};

+	op_and, op_ora, op_rol, op_ror, op_add, op_sub, op_mul, op_div,

+	op_ldr, op_str, op_brk, op_brk, op_brk, op_brk, op_brk, op_brk

+};

 Uint8 opr[][2] = {

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

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

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

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

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

+	{3,1}, {3,1}

 };

 /* clang-format on */

@@ -155,7 +172,7 @@ eval()

 		cpu.literal--;

 		return 1;

 	}

-	if(instr < 24) {

+	if(instr < 32) {

 		if(cpu.wst.ptr < opr[instr][0])

 			return error("Stack underflow");

 		/* TODO stack overflow */

@@ -11,19 +11,17 @@ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

 WITH REGARD TO THIS SOFTWARE.

 */

-#define PRGLEN 256

-#define LABELIDLEN 32

-

 typedef unsigned char Uint8;

+typedef unsigned short Uint16;

 typedef struct {

 	int ptr;

-	Uint8 data[PRGLEN];

+	Uint8 data[65536];

 } Program;

 typedef struct {

-	Uint8 addr;

-	char name[LABELIDLEN];

+	Uint16 addr;

+	char name[64];

 } Label;

 int labelslen;

@@ -34,7 +32,9 @@ Label labels[256];

 char opcodes[][4] = {

 	"BRK", "RTS", "LIT", "POP", "DUP", "SWP", "OVR", "ROT",

 	"JMU", "JSU", "JMC", "JSC", "EQU", "NEQ", "GTH", "LTH",

-	"AND", "ORA", "ROL", "ROR", "ADD", "SUB", "MUL", "DIV"};

+	"AND", "ORA", "ROL", "ROR", "ADD", "SUB", "MUL", "DIV",

+	"LDR", "STR", "---", "---", "---", "---", "---", "---"

+};

 /* clang-format on */

@@ -82,7 +82,7 @@ suca(char *s) /* string to uppercase */

 }

 int

-sihx(char *s)

+sihx(char *s) /* string is hexadecimal */

 {

 	int i = 0;

 	char c;

@@ -107,57 +107,66 @@ shex(char *s) /* string to num */

 	return n;

 }

-#pragma mark - Parser

+int

+ismarker(char *w)

+{

+	return w[0] == '[' || w[0] == ']' || w[0] == '{' || w[0] == '}';

+}

-void

-pushprg(Uint8 hex)

+int

+iscomment(char *w, int *skip)

 {

-	p.data[p.ptr++] = hex;

+	if(w[0] == ')') {

+		*skip = 0;

+		return 1;

+	}

+	if(w[0] == '(') *skip = 1;

+	if(*skip) return 1;

+	return 0;

 }

+#pragma mark - I/O

+

 void

-pushlabel(Label *l)

+pushbyte(Uint8 b, int lit)

 {

-	pushprg(0x02);

-	pushprg(0x01);

-	pushprg(l->addr);

+	if(lit) {

+		pushbyte(0x02, 0);

+		pushbyte(0x01, 0);

+	}

+	p.data[p.ptr++] = b;

 }

 void

-pushliteral(char *w)

+pushshort(Uint16 s, int lit)

 {

-	int len = slen(w) / 2, value = shex(w);

-	pushprg(0x02);

-	pushprg(len);

-	switch(len) {

-	case 1:

-		pushprg(value);

-		break;

-	case 2:

-		pushprg(value >> 8);

-		pushprg(value);

-		break;

-	case 3:

-		pushprg(value >> 16);

-		pushprg(value >> 8);

-		pushprg(value);

-		break;

+	if(lit) {

+		pushbyte(0x02, 0);

+		pushbyte(0x02, 0);

 	}

+	pushbyte((s >> 8) & 0xff, 0);

+	pushbyte(s & 0xff, 0);

 }

-void

-addlabel(char *id, Uint8 addr)

+#pragma mark - Parser

+

+Uint8

+findop(char *s)

 {

-	Label *l = &labels[labelslen++];

-	scpy(suca(id), l->name, LABELIDLEN);

-	l->addr = addr;

-	printf("New label: %s[0x%02x]\n", l->name, l->addr);

+	int i;

+	for(i = 0; i < 32; ++i)

+		if(scmp(opcodes[i], s))

+			return i;

+	return 0;

 }

 void

-addconst(char *id, Uint8 value)

+makelabel(char *id, Uint8 addr)

 {

-	printf("New const: %s[%02x]\n", id, value);

+	Label *l = &labels[labelslen++];

+	scpy(suca(id), l->name, 64);

+	l->addr = addr;

+	printf("New label: %s[0x%02x]\n", l->name, l->addr);

 }

 Label *

@@ -170,94 +179,72 @@ findlabel(char *s)

 	return NULL;

 }

-Uint8

-findop(char *s)

-{

-	int i;

-	for(i = 0; i < 24; ++i)

-		if(scmp(opcodes[i], s))

-			return i;

-	return 0;

-}

-

-int

-ismarker(char *w)

-{

-	return w[0] == '(' || w[0] == ')' || w[0] == '{' || w[0] == '}';

-}

+#pragma mark - Parser

 int

-iscomment(char *w, int *skip)

+error(char *name, char *id)

 {

-	if(w[0] == '>') {

-		*skip = 0;

-		return 1;

-	}

-	if(w[0] == '<') *skip = 1;

-	if(*skip) return 1;

+	printf("Error: %s - %s\n", name, id);

 	return 0;

 }

 int

-getlength(char *w)

-{

-	if(findop(w) || scmp(w, "BRK")) return 1;

-	if(w[0] == '.') return 3;

-	if(w[0] == ':') return 0;

-	if(w[0] == ';') return 0;

-	if(w[0] == '@') return 0;

-	if(sihx(w)) { return slen(w) / 2 + 2; }

-	if(ismarker(w)) return 0;

-	printf("Unknown length %s\n", w);

-	return 0;

-}

-

-void

 pass1(FILE *f)

 {

-	int skip = 0;

-	int addr = 0;

-	int vars = 0;

-	char word[64];

-	while(fscanf(f, "%s", word) == 1) {

-		if(iscomment(word, &skip)) continue;

-		if(word[0] == ':') addlabel(word + 1, addr);

-		if(word[0] == ';') addlabel(word + 1, vars++);

-		addr += getlength(word);

+	int skip = 0, addr = 0, vars = 0;

+	char w[64];

+	while(fscanf(f, "%s", w) == 1) {

+		if(iscomment(w, &skip)) continue;

+		if(w[0] == ':') makelabel(w + 1, addr);

+		if(w[0] == ';') makelabel(w + 1, vars++);

+		/* move addr ptr */

+		if(findop(w) || scmp(w, "BRK"))

+			addr += 1;

+		else if(w[0] == '@')

+			addr += 0;

+		else if(w[0] == ':')

+			addr += 0;

+		else if(w[0] == ';')

+			addr += 0;

+		else if(w[0] == '.')

+			addr += 2;

+		else if(w[0] == ',')

+			addr += 4;

+		else if(ismarker(w))

+			addr += 0;

+		else

+			return error("Unknown label(pass1)", w);

 	}

 	rewind(f);

+	return 1;

 }

-void

+int

 pass2(FILE *f)

 {

 	int skip = 0;

-	char word[64];

-	while(fscanf(f, "%s", word) == 1) {

+	char w[64];

+	while(fscanf(f, "%s", w) == 1) {

 		Uint8 op = 0;

 		Label *l;

-		if(word[0] == ':') continue;

-		if(word[0] == ';') continue;

-		suca(word);

-		if(iscomment(word, &skip) || ismarker(word)) continue;

-		if(word[0] == '@')

-			p.ptr = shex(word + 1);

-		else if((op = findop(word)) || scmp(word, "BRK"))

-			pushprg(op);

-		else if((l = findlabel(word + 1)))

-			pushlabel(l);

-		else if(sihx(word))

-			pushliteral(word);

+		if(w[0] == ':') continue;

+		if(w[0] == ';') continue;

+		suca(w);

+		if(iscomment(w, &skip) || ismarker(w)) continue;

+		if(w[0] == '@')

+			p.ptr = shex(w + 1);

+		else if((op = findop(w)) || scmp(w, "BRK"))

+			pushbyte(op, 0);

+		else if((l = findlabel(w + 1)))

+			pushshort(l->addr, w[0] == ',');

+		else if(sihx(w + 1) && slen(w + 1) == 2)

+			pushbyte(shex(w + 1), w[0] == ',');

+		else if(sihx(w + 1) && slen(w + 1) == 4)

+			pushshort(shex(w + 1), w[0] == ',');

 		else

-			printf("Unknown label: %s\n", word);

+			return error("Unknown label(pass2)", w);

 	}

-}

-

-int

-error(char *name)

-{

-	printf("Error: %s\n", name);

-	return 0;

+	return 1;

 }

 int

@@ -265,11 +252,11 @@ main(int argc, char *argv[])

 {

 	FILE *f;

 	if(argc < 3)

-		return error("No input.");

+		return error("Input", "Missing");

 	if(!(f = fopen(argv[1], "r")))

-		return error("Missing input.");

-	pass1(f);

-	pass2(f);

+		return error("Open", "Failed");

+	if(!pass1(f) || !pass2(f))

+		return error("Assembly", "Failed");

 	fwrite(p.data, sizeof(p.data), 1, fopen(argv[2], "wb"));

 	fclose(f);

 	return 0;