diff --git a/.gitignore b/.gitignore
index 37d3d43..e20c756 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 *.o
 first
 test.rom
+make.deps
diff --git a/Makefile b/Makefile
index 6ee73f9..0a66dc8 100644
--- a/Makefile
+++ b/Makefile
@@ -2,7 +2,13 @@ QUIET=1
 
 all:first
 
-OBJECT_FILES=gui.o main.o simdata.o assembly.o
+OBJECT_FILES=gui.o main.o simdata.o assembly.o cpu.o
+
+make.deps: $(subst .o,.c,${OBJECT_FILES}) $(wildcard *.h)
+	    @$(CC)  -MM $(subst .o,.c,${OBJECT_FILES}) > make.deps
+
+include make.deps
+
 
 ifeq "${QUIET}" "1"
        QUIET_CC     = @echo   ' CC    '$@;
diff --git a/cpu.c b/cpu.c
new file mode 100644
index 0000000..2c703a8
--- /dev/null
+++ b/cpu.c
@@ -0,0 +1,136 @@
+#include "simdata.h"
+#include "cpu.h"
+#include <stdlib.h>
+
+
+
+struct fetch_data_t *malloc_fetch_data(){
+	return NULL;
+}
+void free_fetch_data(__attribute__((unused)) struct fetch_data_t *tofree){
+}
+int fetch(struct simdata_t *simdata){
+	simdata->decode_data->in_bytecode=(uint32_t)(simdata->RAM[simdata->PC])<<24|(uint32_t)(simdata->RAM[simdata->PC+1])<<16|(uint32_t)(simdata->RAM[simdata->PC+2])<<8|(uint32_t)(simdata->RAM[simdata->PC+3]);
+	simdata->PC+=4;
+	return 0;
+}
+
+
+
+
+struct decode_data_t *malloc_decode_data(){
+	return malloc(sizeof(struct decode_data_t));
+}
+void free_decode_data(struct decode_data_t *tofree){
+	free(tofree);
+}
+int decode(struct simdata_t *simdata){
+	uint16_t opcode;
+	switch((simdata->decode_data->in_bytecode&0xE0000000)>>29){
+		case 0:
+			opcode=(simdata->decode_data->in_bytecode&0x1F000000)>>24;
+			switch(opcode){
+				case 1:
+					simdata->exec_data->out_op->OP_ADDR=IMMEDIATE;
+					simdata->exec_data->out_op->data=simdata->decode_data->in_bytecode&0x00FFFFFF;
+					simdata->exec_data->EXEC_ACTION=JUMP;
+					break;
+				default:
+					return 1;
+			}
+			break;
+		case 1:
+			return 1;
+			break;
+		case 2:
+			return 1;
+			break;
+		default:
+			return 1;
+	}
+	return 0;
+}
+
+
+
+
+struct exec_data_t *malloc_exec_data(){
+	struct exec_data_t *ret;
+	ret=malloc(sizeof(struct exec_data_t));
+	if(!ret)
+		return 0;
+	ret->in_op1=malloc(sizeof(struct exec_op_t));
+	if(!ret->in_op1){
+		free(ret);
+		return 0;
+	}
+	ret->in_op2=malloc(sizeof(struct exec_op_t));
+	if(!ret->in_op2){
+		free(ret->in_op1);
+		free(ret);
+		return 0;
+	}
+	ret->out_op=malloc(sizeof(struct exec_op_t));
+	if(!ret->out_op){
+		free(ret->in_op1);
+		free(ret->in_op2);
+		free(ret);
+		return 0;
+	}
+	return ret;
+}
+void free_exec_data(struct exec_data_t *tofree){
+	free(tofree->in_op1);
+	free(tofree->in_op2);
+	free(tofree->out_op);
+	free(tofree);
+}
+int exec(struct simdata_t *simdata){
+	switch(simdata->exec_data->EXEC_ACTION){
+		case JUMP:
+			if(simdata->exec_data->out_op->OP_ADDR==IMMEDIATE)
+				simdata->PC=simdata->exec_data->out_op->data;
+			else
+				return 1;
+			break;
+		case EXEC_ALU:
+			return 1;
+	}
+	return 0;
+}
+
+
+
+
+
+int state=0;
+
+int cpu_cycle_clock(struct simdata_t *simdata){
+	switch(state){
+		case 0: if( fetch(simdata)  ) return 1; break;
+		case 1: if( decode(simdata) ) return 1; break;
+		case 2: if( exec(simdata)   ) return 1; break;
+	}
+	if(state==2)
+		state=0;
+	else
+		state++;
+	return 0;
+}
+
+
+int cpu_simdata_malloc(struct simdata_t *simdata){
+	simdata->fetch_data=malloc_fetch_data();
+	simdata->decode_data=malloc_decode_data();
+	simdata->exec_data=malloc_exec_data();
+	if((simdata->fetch_data!=NULL)&&(simdata->decode_data!=NULL)&&(simdata->exec_data!=NULL))
+		return 1;
+	else
+		return 0;
+}
+
+void cpu_simdata_free(struct simdata_t *simdata){
+	free_fetch_data(simdata->fetch_data);
+	free_decode_data(simdata->decode_data);
+	free_exec_data(simdata->exec_data);
+}
diff --git a/cpu.h b/cpu.h
new file mode 100644
index 0000000..6632a62
--- /dev/null
+++ b/cpu.h
@@ -0,0 +1,54 @@
+#ifndef CPU_HEADER
+#include "simdata.h"
+
+struct fetch_data_t{
+
+};
+struct decode_data_t{
+	uint32_t in_bytecode;
+};
+
+
+
+
+///// EXEC DATA STRUCTURES ///////
+enum EXEC_ACTION_t {
+	EXEC_ALU,
+	JUMP
+};
+
+enum ALU_OP_t {
+	ALU_ADD,
+	ALU_SUB,
+	ALU_SL,
+	ALU_SR,
+	ALU_CMP
+};
+
+enum OP_ADDR_t {
+	IMMEDIATE,
+	REGISTER,
+};
+
+struct exec_op_t {
+	enum OP_ADDR_t OP_ADDR;
+	uint32_t data;
+};
+
+
+struct exec_data_t {
+	enum EXEC_ACTION_t EXEC_ACTION;
+	enum ALU_OP_t ALU_OP;
+	struct exec_op_t *in_op1;
+	struct exec_op_t *in_op2;
+	struct exec_op_t *out_op;
+};
+
+
+
+void cpu_simdata_free(struct simdata_t *simdata);
+int cpu_simdata_malloc(struct simdata_t *simdata);
+int cpu_cycle_clock(struct simdata_t *simdata);
+
+#endif
+#define CPU_HEADER
diff --git a/gui.c b/gui.c
index 0b9a95b..41c943b 100644
--- a/gui.c
+++ b/gui.c
@@ -170,6 +170,7 @@ int gui_error(char *str){
 }
 
 int update_general_disas(struct simdata_t *simdata){
+	wclear(general_disas);
 	int width,height;
 	getmaxyx(general_disas,height,width);
 	box(general_disas, 0 , 0);
@@ -219,6 +220,7 @@ int update_general_disas(struct simdata_t *simdata){
 }
 
 int update_general_stack(struct simdata_t *simdata){
+	wclear(general_stack);
 	int width,height;
 	getmaxyx(general_stack,height,width);
 	box(general_stack, 0 , 0);
@@ -275,6 +277,7 @@ int update_general_stack(struct simdata_t *simdata){
 }
 
 int update_general_memdump(struct simdata_t *simdata){
+	wclear(general_memdump);
 	int width,height;
 	getmaxyx(general_memdump,height,width);
 	box(general_memdump, 0 , 0);
@@ -292,7 +295,7 @@ int update_general_memdump(struct simdata_t *simdata){
 			wprintw(general_memdump,"%06x  ",ADDRESS);
 			uint32_t temp_address=ADDRESS;
 			for (int i=0;i<n;i++){
-				if(ADDRESS>=simdata->PC&&ADDRESS<=simdata->PC+4)
+				if(ADDRESS>=simdata->PC&&ADDRESS<=simdata->PC+3)
 					wattron(general_memdump,A_BOLD);
 				else
 					wattroff(general_memdump,A_BOLD);
@@ -301,7 +304,7 @@ int update_general_memdump(struct simdata_t *simdata){
 			}
 			ADDRESS=temp_address;
 			for (int i=0;i<n;i++){
-				if(ADDRESS>=simdata->PC&&ADDRESS<=simdata->PC+4)
+				if(ADDRESS>=simdata->PC&&ADDRESS<=simdata->PC+3)
 					wattron(general_memdump,A_BOLD);
 				else
 					wattroff(general_memdump,A_BOLD);
diff --git a/main.c b/main.c
index a912457..06952dc 100644
--- a/main.c
+++ b/main.c
@@ -24,6 +24,7 @@
 #include <unistd.h>
 #include <errno.h>
 #include "assembly.h"
+#include "cpu.h"
 
 void help(char* progname){
 	printf("Usage: %s  -i <file> \n", progname);
@@ -71,6 +72,10 @@ int main(int argc, char* argd[] ){
 	FILE* rom=fopen(infile,"r");
 
 	struct simdata_t *simdata = init_simdata();
+	if(!simdata){
+		printf("Couldn't allocate memory\n");
+		return 1;
+	}
 
 	if ( assemble != NULL ){
 		/* RUN ASSEMBLER */
@@ -127,7 +132,7 @@ int main(int argc, char* argd[] ){
 		fseek(rom, 0, SEEK_SET);
 
 		if(!simdata){
-			gui_error("failed to initialise simdata");
+			gui_error("failed to initialise simdata\n");
 			fclose(rom);
 			free_simdata(simdata);
 			return 1;
@@ -144,25 +149,42 @@ int main(int argc, char* argd[] ){
 		/// INITIALISE GUI ///
 		if(start_gui()){
 			printf("Failed on start_gui()\n");
+			cpu_simdata_free(simdata);
 			free_simdata(simdata);
 			return 1;
 		}
 
-		update_gui(simdata);
+		cpu_simdata_malloc(simdata);
 
-		if(gui_continue_request()){
-			end_gui();
-			printf("Failed on gui_continue_request()\n");
-			free_simdata(simdata);
-			return 1;
+		while(1){
+			update_gui(simdata);
+
+			if(gui_continue_request()){
+				end_gui();
+				printf("Failed on gui_continue_request()\n");
+				cpu_simdata_free(simdata);
+				free_simdata(simdata);
+				return 1;
+			}
+
+			if(cpu_cycle_clock(simdata)){
+				cpu_simdata_free(simdata);
+				free_simdata(simdata);
+				end_gui();
+				printf("Failed to execute instruction\n");
+				return 1;
+			}
 		}
 
 		if(end_gui()){
 			printf("Failed on end_gui()\n");
+			cpu_simdata_free(simdata);
 			free_simdata(simdata);
 			return 1;
 		}
 
+
+		cpu_simdata_free(simdata);
 		free_simdata(simdata);
 	}
 	return 0;
diff --git a/simdata.h b/simdata.h
index 4a51d94..b689a18 100644
--- a/simdata.h
+++ b/simdata.h
@@ -6,6 +6,9 @@ struct simdata_t{
 	uint8_t *RAM;
 	uint32_t PC;
 	uint32_t SP;
+	struct fetch_data_t *fetch_data;
+	struct decode_data_t *decode_data;
+	struct exec_data_t *exec_data;
 };
 
 struct simdata_t *init_simdata();
@@ -17,5 +20,6 @@ enum CPU_STATE_t{
 	SINGLE_STEPPING,
 	STOPPED
 };
+
 #endif
 #define SIMDATA_HEADER
diff --git a/test.asm b/test.asm
index b7a8abd..d21cc29 100644
--- a/test.asm
+++ b/test.asm
@@ -1,4 +1,6 @@
-JMP $ABCDEF
+JMP $000008
+SL %R7
+JMP $000000
 JMP,NZ $DEADBA
 JMP,C $EEEEEF
 SL %R7