diff --git a/docs/draw.ul b/docs/draw.ul
index 4c05356..8f4b9c4 100644
--- a/docs/draw.ul
+++ b/docs/draw.ul
@@ -1,46 +1,78 @@
-Device screen("/dev/screen/0");
-u8[] colors = [0,255,36,73,146,182,128,224,144,
-252,9,18,12,16,28,159,2,3,10,19,131,147,130,227,129,226,
-72,141,136,241,208,244];
+str screen_namespace = "/dev/screen/0";
+str mouse_namespace = "/dev/mouse/0";
+byte selected_color = 255;
 
-fn main() {
+const byte BLACK = 0;
+const byte WHITE = 255;
+const byte DARK_GRAY = 73;
+const byte GRAY = 146;
+const byte LIGHT_GRAY = 182;
+
+function main() {
+    Device screen(screen_namespace);
     screen.open(0);
+
+    Device mouse(mouse_namespace);
+    mouse.open(0);
+
+    outline_swatch(screen, BLACK, 1, 1);
+    outline_swatch(screen, WHITE, 21, 1);
     screen.draw();
 
-    int x = 10;
-    int y = 20;
-    for (int i = 0; i < colors.length; i+=2) {
-        draw_outline_swatch(colors[i], x, y);
-        draw_outline_swatch(colors[i + 1], x + 20, y);
-        x += 20;
-        y += 20;
+    while (true) {
+        mouse.read();
+        if (mouse.btn1) {
+            int box_size = 20;
+            int x = 1;
+            int y = 1;
+            byte color = BLACK;
+            outlined_swatch(screen, color, x, y);
+            set_color_if_clicked(box_size, x, y, mouse.x, mouse.y, color, mouse.btn1);
+
+            color = WHITE;
+            x = 21;
+            outlined_swatch(screen, color, x, y);
+            set_color_if_clicked(box_size, x, y, mouse.x, mouse.y, color, mouse.btn1);
+            screen.draw();
+
+            box(screen, selected_color, x, y, 5, 5);
+        }
     }
-    screen.draw();
     exit(0);
 }
 
-fn draw_outline_swatch(u8 color, int x, int y) {
-    u8 gray = colors[5];
-    int outline_size = 20;
-    int fill_size = 17;
-    int offset = 2;
+function set_color_if_clicked(int box_size, int bx, int by, int mx, int my, byte color, bool btn1_down) {
+    int right = bx + box_size;
+    int bottom = by + box_size;
+
+    if (mx < mx) return;
+    if (mx > right) return;
+    if (my < by) return;
+    if (my > bottom) return;
+    if (not btn1_down) return;
+
+    selected_color = color;
 
-    draw_box(gray, x, y, outline_size, outline_size);
-    int swatch_pos = x + 2;
-    int offset_pos = y + 2;
-    draw_box(color, swatch_pos, offset_pos, fill_size, fill_size);
     return;
 }
 
-fn draw_box(u8 color, int x, int y, int width, int height) {
-    int screen_width = screen.width;
-    int pos = y * 640 + x;
-
-    do (int i = height; i > 0; i--) {
-        int row = pos + width;
-        int pixel = offset;
-        do (int j = ; pos;j++) {
-            screen.buffer[j] = color;
-        }
+function outline_swatch(ref Device screen, byte color, int x, int y) {
+    byte bg_color = GRAY;
+    if (selected_color == color) {
+        bg_color = DARK_GRAY;
     }
-}
\ No newline at end of file
+
+    box(screen, bg_color, x, y, 20, 20);
+    box(screen, color, x + 2, y + 2, 17, 17);
+    return;
+}
+
+function box(ref Device screen, byte color, int x, int y, int width, int height) {
+   int pixel = y * width + x + &screen.buffer + 4;
+   do (int i = height, i > 0, i--) {
+     int row = pixel + width;
+     screen.set(row, color, width);
+     pixel += width;
+   }
+   return;
+}
diff --git a/src/arch/emscripten/devices.c b/src/arch/emscripten/devices.c
index 3938612..00b376d 100644
--- a/src/arch/emscripten/devices.c
+++ b/src/arch/emscripten/devices.c
@@ -5,9 +5,11 @@
 #include <emscripten/html5.h>
 
 
-i32 console_open(void *data, u32 mode) {
+i32 console_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size) {
   USED(mode);
   USED(data);
+  USED(buffer);
+  USED(size);
   return 0;
 }
 
@@ -41,18 +43,23 @@ i32 console_ioctl(void *data, u32 cmd, const u8 *buffer) {
   return -1;
 }
 
-i32 screen_open(void *data, u32 mode) {
+i32 screen_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size) {
   USED(mode);
   ScreenDeviceData *screen = (ScreenDeviceData *)data;
 
   // Initialize with proper values
   screen->width = 640;
   screen->height = 480;
-  screen->size = 640 * 480;
+  screen->size = 640 * 480 + 12;
   screen->window = NULL;
   screen->renderer = NULL;
   screen->texture = NULL;
 
+  u8 *info = (u8 *)buffer;
+  memcpy(&info[0], &screen->width, sizeof(u32));
+  memcpy(&info[4], &screen->height, sizeof(u32));
+  memcpy(&info[8], &screen->size, sizeof(u32));
+
   #ifdef __EMSCRIPTEN__
   emscripten_set_canvas_element_size("#canvas", screen->width, screen->height);
   #endif
@@ -161,30 +168,13 @@ i32 screen_read(void *data, u8 *buffer, u32 size) {
 }
 
 i32 screen_ioctl(void *data, u32 cmd, const u8 *buffer) {
-  ScreenDeviceData *screen = (ScreenDeviceData *)data;
-
-  switch (cmd) {
-  case IOCTL_GET_INFO: {
-    u8 *info = (u8 *)buffer;
-    u32 size;
-    memcpy(&size, &info[0], sizeof(u32));
-
-    if (size < 16) {
-      return -1;
-    }
-
-    memcpy(&info[4], &screen->pos, sizeof(u32));
-    memcpy(&info[8], &screen->size, sizeof(u32));
-    memcpy(&info[12], &screen->width, sizeof(u32));
-    memcpy(&info[16], &screen->height, sizeof(u32));
-    return 0;
-  }
-  default:
-    return -1;
-  }
+  USED(data);
+  USED(cmd);
+  USED(buffer);
+  return 0;
 }
 
-i32 mouse_open(void *data, u32 mode) {
+i32 mouse_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size) {
   USED(mode);
   return 0;
 }
@@ -216,9 +206,10 @@ i32 mouse_close(void *data) {
   return 0;
 }
 
-i32 keyboard_open(void *data, u32 mode) {
+i32 keyboard_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size) {
   USED(data);
   USED(mode);
+  USED(buffer);
   return 0;
 }
 
diff --git a/src/arch/emscripten/devices.h b/src/arch/emscripten/devices.h
index 526b37d..48578e5 100644
--- a/src/arch/emscripten/devices.h
+++ b/src/arch/emscripten/devices.h
@@ -1,14 +1,13 @@
 #include "../../vm/vm.h"
 #include <SDL2/SDL.h>
 
-#define IOCTL_GET_INFO 0x01
-
 typedef struct screen_device_data_s {
+    u32 handle;
     u32 width;
     u32 height;
-    u32 pos;
     u32 size;
     u8 *screen_buffer;
+    u32 pos;
     bool update;
     SDL_Window *window;
     SDL_Renderer *renderer;
@@ -17,6 +16,7 @@ typedef struct screen_device_data_s {
 
 /* Mouse device data */
 typedef struct mouse_device_data_s {
+    u32 handle;
     u32 x;
     u32 y;
     u8 btn1;
@@ -29,29 +29,36 @@ typedef struct mouse_device_data_s {
 
 /* Keyboard device data */
 typedef struct keyboard_device_data_s {
+    u32 handle;
+    i32 key_count;    
     const u8 *keys;
-    i32 key_count;
     u32 pos;
     u32 size;
 } KeyboardDeviceData;
 
-i32 screen_open(void *data, u32 mode);
+/* Console device data */
+typedef struct console_device_data_s {
+    u32 handle;
+    u32 size;
+} ConsoleDeviceData;
+
+i32 screen_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size);
 i32 screen_read(void *data, u8 *buffer, u32 size);
 i32 screen_write(void *data, const u8 *buffer, u32 size);
 i32 screen_close(void *data);
 i32 screen_ioctl(void *data, u32 cmd, const u8 *buffer);
 
-i32 mouse_open(void *data, u32 mode);
+i32 mouse_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size);
 i32 mouse_read(void *data, u8 *buffer, u32 size);
 i32 mouse_write(void *data, const u8 *buffer, u32 size);
 i32 mouse_close(void *data);
 
-i32 keyboard_open(void *data, u32 mode);
+i32 keyboard_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size);
 i32 keyboard_read(void *data, u8 *buffer, u32 size);
 i32 keyboard_write(void *data, const u8 *buffer, u32 size);
 i32 keyboard_close(void *data);
 
-i32 console_open(void *data, u32 mode);
+i32 console_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size);
 i32 console_read(void *data, u8 *buffer, u32 size);
 i32 console_write(void *data, const u8 *buffer, u32 size);
 i32 console_close(void *data);
diff --git a/src/arch/linux/devices.c b/src/arch/linux/devices.c
index 5e704e1..009c6ed 100644
--- a/src/arch/linux/devices.c
+++ b/src/arch/linux/devices.c
@@ -3,10 +3,14 @@
 #include <string.h>
 #include <unistd.h>
 
-i32 console_open(void *data, u32 mode) {
+i32 console_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size) {
   USED(mode);
-  USED(data);
-  /* Nothing to open — stdin/stdout are always available */
+  USED(size);
+  ConsoleDeviceData *console = (ConsoleDeviceData *)data;
+  console->handle = handle;
+
+  u8 *info = (u8 *)buffer;
+  memcpy(&info[0], &console->handle, sizeof(u32));
   return 0; /* Success */
 }
 
@@ -44,9 +48,17 @@ i32 console_ioctl(void *data, u32 cmd, const u8 *buffer) {
   return -1; /* Unsupported */
 }
 
-i32 screen_open(void *data, u32 mode) {
+i32 screen_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size) {
   USED(mode);
+  USED(size);
   ScreenDeviceData *screen = (ScreenDeviceData *)data;
+  screen->handle = handle;
+
+  u8 *info = (u8 *)buffer;
+  memcpy(&info[0], &screen->handle, sizeof(u32));
+  memcpy(&info[4], &screen->width, sizeof(u32));
+  memcpy(&info[8], &screen->height, sizeof(u32));
+  memcpy(&info[12], &screen->size, sizeof(u32));
 
   screen->window =
       SDL_CreateWindow("Reality Engine VM", SDL_WINDOWPOS_CENTERED,
@@ -111,34 +123,21 @@ i32 screen_close(void *data) {
 }
 
 i32 screen_ioctl(void *data, u32 cmd, const u8 *buffer) {
-  ScreenDeviceData *screen = (ScreenDeviceData *)data;
-
-  switch (cmd) {
-  case IOCTL_GET_INFO: {
-    u8 *info = (u8 *)buffer;
-    u32 size;
-    memcpy(&size, &info[0], sizeof(u32));
-
-    if (size < 16) {
-      return -1;
-    }
-
-    memcpy(&info[4], &screen->pos, sizeof(u32));
-    memcpy(&info[8], &screen->size, sizeof(u32));
-    memcpy(&info[12], &screen->width, sizeof(u32));
-    memcpy(&info[16], &screen->height, sizeof(u32));
-    return 0;
-  }
-
-  default:
-    return -1; // Error
-  }
+  USED(data);
+  USED(cmd);
+  USED(buffer);
+  return 0;
 }
 
 /* MOUSE */
-i32 mouse_open(void *data, u32 mode) {
-  USED(data);
+i32 mouse_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size) {
   USED(mode);
+  USED(size);
+  MouseDeviceData *mouse = (MouseDeviceData *)data;
+  mouse->handle = handle;
+
+  u8 *info = (u8 *)buffer;
+  memcpy(&info[0], &mouse->handle, sizeof(u32));
   return 0;
 }
 
@@ -160,12 +159,12 @@ i32 mouse_read(void *data, u8 *buffer, u32 size) {
   mouse_data->btn4 = (state & SDL_BUTTON(SDL_BUTTON_X1)) ? 1 : 0;
 
   u8 *info = (u8 *)buffer;
-  memcpy(&info[0], &mouse_data->x, sizeof(u32));
-  memcpy(&info[4], &mouse_data->y, sizeof(u32));
-  memcpy(&info[8], &mouse_data->btn1, sizeof(u8));
-  memcpy(&info[9], &mouse_data->btn2, sizeof(u8));
-  memcpy(&info[10], &mouse_data->btn3, sizeof(u8));
-  memcpy(&info[11], &mouse_data->btn4, sizeof(u8));
+  memcpy(&info[4], &mouse_data->x, sizeof(u32));
+  memcpy(&info[8], &mouse_data->y, sizeof(u32));
+  memcpy(&info[9], &mouse_data->btn1, sizeof(u8));
+  memcpy(&info[10], &mouse_data->btn2, sizeof(u8));
+  memcpy(&info[11], &mouse_data->btn3, sizeof(u8));
+  memcpy(&info[12], &mouse_data->btn4, sizeof(u8));
   return 0;
 }
 
@@ -181,9 +180,15 @@ i32 mouse_close(void *data) {
   return 0;
 }
 
-i32 keyboard_open(void *data, u32 mode) {
-  USED(data);
+i32 keyboard_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size) {
   USED(mode);
+  USED(size);
+  KeyboardDeviceData *kbd = (KeyboardDeviceData *)data;
+  kbd->handle = handle;
+
+  u8 *info = (u8 *)buffer;
+  memcpy(&info[0], &kbd->handle, sizeof(u32));
+
   return 0;
 }
 
@@ -193,7 +198,8 @@ i32 keyboard_read(void *data, u8 *buffer, u32 size) {
   if (size < (u32)kbd->key_count)
     return -1;
 
-  memcpy(buffer, kbd->keys, kbd->key_count);
+  u8 *info = (u8 *)buffer;
+  memcpy(&info[4], kbd->keys, kbd->key_count);
   return 0;
 }
 
diff --git a/src/arch/linux/devices.h b/src/arch/linux/devices.h
index 29b1343..f4bad6e 100644
--- a/src/arch/linux/devices.h
+++ b/src/arch/linux/devices.h
@@ -6,9 +6,9 @@
 
 /* Screen device data */
 typedef struct screen_device_data_s {
+    u32 handle;
     u32 width;
     u32 height;
-    u32 pos;
     u32 size;
     u8 *screen_buffer;
     u32 update;
@@ -19,41 +19,48 @@ typedef struct screen_device_data_s {
 
 /* Mouse device data */
 typedef struct mouse_device_data_s {
+    u32 handle;
     u32 x;
     u32 y;
     u8 btn1;
     u8 btn2;
     u8 btn3;
     u8 btn4;
-    u32 pos;
     u32 size;
 } MouseDeviceData;
 
 /* Keyboard device data */
 typedef struct keyboard_device_data_s {
+    u32 handle;
     const u8 *keys;
     i32 key_count;
     u32 pos;
     u32 size;
 } KeyboardDeviceData;
 
-i32 screen_open(void *data, u32 mode);
+/* Console device data */
+typedef struct console_device_data_s {
+    u32 handle;
+    u32 size;
+} ConsoleDeviceData;
+
+i32 screen_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size);
 i32 screen_read(void *data, u8 *buffer, u32 size);
 i32 screen_write(void *data, const u8 *buffer, u32 size);
 i32 screen_close(void *data);
 i32 screen_ioctl(void *data, u32 cmd, const u8 *buffer);
 
-i32 mouse_open(void *data, u32 mode);
+i32 mouse_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size);
 i32 mouse_read(void *data, u8 *buffer, u32 size);
 i32 mouse_write(void *data, const u8 *buffer, u32 size);
 i32 mouse_close(void *data);
 
-i32 keyboard_open(void *data, u32 mode);
+i32 keyboard_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size);
 i32 keyboard_read(void *data, u8 *buffer, u32 size);
 i32 keyboard_write(void *data, const u8 *buffer, u32 size);
 i32 keyboard_close(void *data);
 
-i32 console_open(void *data, u32 mode);
+i32 console_open(void *data, u32 mode, u32 handle, u8 *buffer, u32 size);
 i32 console_read(void *data, u8 *buffer, u32 size);
 i32 console_write(void *data, const u8 *buffer, u32 size);
 i32 console_close(void *data);
diff --git a/src/arch/linux/main.c b/src/arch/linux/main.c
index bbe641c..ed4f469 100644
--- a/src/arch/linux/main.c
+++ b/src/arch/linux/main.c
@@ -39,6 +39,7 @@ static DeviceOps console_device_ops = {
 static ScreenDeviceData screen_data = {0};
 static MouseDeviceData mouse_data = {0};
 static KeyboardDeviceData keyboard_data = {0};
+static ConsoleDeviceData console_data = {0};
 
 // Function to save VM state to ROM file
 bool saveVM(const char *filename, VM *vm) {
@@ -382,7 +383,9 @@ i32 main(i32 argc, char *argv[]) {
     return EXIT_SUCCESS;
   }
 
-  vm_register_device(&vm, "/dev/term/0", "terminal", nil, &console_device_ops);
+  vm_register_device(&vm, "/dev/term/0", "terminal", &console_data,
+                     &console_device_ops, 4);
+
   if (gui_mode) {
     if (SDL_Init(SDL_INIT_VIDEO) < 0) {
       printf("SDL initialization failed: %s\n", SDL_GetError());
@@ -395,7 +398,7 @@ i32 main(i32 argc, char *argv[]) {
     screen_data.size = screen_data.width * screen_data.height;
 
     vm_register_device(&vm, "/dev/screen/0", "screen", &screen_data,
-                       &screen_ops);
+                       &screen_ops, 16 + screen_data.size);
 
     mouse_data.x = 0;
     mouse_data.y = 0;
@@ -403,13 +406,14 @@ i32 main(i32 argc, char *argv[]) {
     mouse_data.btn2 = 0;
     mouse_data.btn3 = 0;
     mouse_data.btn4 = 0;
-    mouse_data.size = 12;
+    mouse_data.size = 16;
 
-    vm_register_device(&vm, "/dev/mouse/0", "mouse", &mouse_data, &mouse_ops);
+    vm_register_device(&vm, "/dev/mouse/0", "mouse", &mouse_data, &mouse_ops,
+                       mouse_data.size);
 
     keyboard_data.keys = SDL_GetKeyboardState(&keyboard_data.key_count);
     vm_register_device(&vm, "/dev/keyboard/0", "keyboard", &keyboard_data,
-                       &keyboard_ops);
+                       &keyboard_ops, keyboard_data.key_count + 4);
 
     SDL_Event event;
     bool running = true;
diff --git a/src/tools/assembler.c b/src/tools/assembler.c
index e265f52..e659ccc 100644
--- a/src/tools/assembler.c
+++ b/src/tools/assembler.c
@@ -75,8 +75,7 @@ int get_instruction_byte_size(ExprNode *node) {
   }
 
   // Register-based opcodes (2 bytes: opcode + register)
-  if (strcmp(opname, "pop") == 0 || strcmp(opname, "jump-if-flag") == 0 ||
-      strcmp(opname, "jump") == 0 || strcmp(opname, "push") == 0) {
+  if (strcmp(opname, "pop") == 0 || strcmp(opname, "push") == 0) {
     return 2;
   }
 
@@ -111,7 +110,8 @@ int get_instruction_byte_size(ExprNode *node) {
   }
 
   // (5 bytes: 1 + 4)
-  if (strcmp(opname, "call") == 0) {
+  if (strcmp(opname, "call") == 0 || strcmp(opname, "jump-if-flag") == 0 ||
+      strcmp(opname, "jump") == 0) {
     return 5;
   }
 
diff --git a/src/vm/device.c b/src/vm/device.c
index 5d93c9f..ec022d4 100644
--- a/src/vm/device.c
+++ b/src/vm/device.c
@@ -2,7 +2,7 @@
 #include "str.h"
 
 i32 vm_register_device(VM *vm, const char *path, const char *type, void *data,
-                       DeviceOps *ops) {
+                       DeviceOps *ops, u32 size) {
   Device *dev;
 
   if (vm->dc >= DEVICES_SIZE)
@@ -18,6 +18,7 @@ i32 vm_register_device(VM *vm, const char *path, const char *type, void *data,
 
   dev->data = data;
   dev->ops = ops;
+  dev->size = size;
   dev->flags = 0;
   return dev->handle;
 }
diff --git a/src/vm/device.h b/src/vm/device.h
index 4b29d93..00d9735 100644
--- a/src/vm/device.h
+++ b/src/vm/device.h
@@ -3,7 +3,7 @@
 
 #include "opcodes.h"
 
-i32 vm_register_device(VM *vm, const char *path, const char *type, void *data, DeviceOps *ops);
+i32 vm_register_device(VM *vm, const char *path, const char *type, void *data, DeviceOps *ops, u32 size);
 Device* find_device_by_path(VM *vm, const char *path);
 Device* find_device_by_type(VM *vm, const char *type);
 i32 find_devices_by_type(VM *vm, const char *type, Device **results, uint32_t max_results);
diff --git a/src/vm/opcodes.h b/src/vm/opcodes.h
index f1811f6..a589c30 100644
--- a/src/vm/opcodes.h
+++ b/src/vm/opcodes.h
@@ -102,7 +102,7 @@ typedef enum {
 } SyscallID;
 
 typedef struct device_ops_s {
-  i32 (*open)(void *device_data, u32 mode);
+  i32 (*open)(void *device_data, u32 mode, u32 handle, u8 *buffer, u32 size);
   i32 (*read)(void *device_data, u8 *buffer, u32 size);
   i32 (*write)(void *device_data, const u8 *buffer, u32 size);
   i32 (*close)(void *device_data);
@@ -121,6 +121,7 @@ typedef struct device_s {
   DeviceOps *ops;                    /* operations vtable */
   u32 flags;                         /* permissions, status, etc. */
   u32 handle;                        /* id for fast access in VM */
+  u32 size;                        /* id for fast access in VM */
 } Device;
 
 #define MEMORY_SIZE (640 * 480 + 65536)
diff --git a/src/vm/vm.c b/src/vm/vm.c
index 0253eb9..bb12524 100644
--- a/src/vm/vm.c
+++ b/src/vm/vm.c
@@ -355,17 +355,15 @@ bool step_vm(VM *vm) {
     return true;
   }
   case OP_JMP: {
-    dest = read_u8(vm, code, vm->pc);
-    vm->pc++;
-    vm->pc = frame->registers[dest]; /* Jump to address */
+    u32 jmp = read_u32(vm, code, vm->pc);
+    vm->pc = jmp; /* Jump to address */
     return true;
   }
   case OP_JMPF: { /* error handling for syscall, jump if flag == 0 */
     u32 mask;
-    dest = read_u8(vm, code, vm->pc);
-    vm->pc++;
+    u32 jmp = read_u32(vm, code, vm->pc);
     mask = -(u32)(vm->flag == 0);
-    vm->pc = (dest & mask) | (vm->pc & ~mask);
+    vm->pc = (jmp & mask) | (vm->pc & ~mask);
     return true;
   }
   case OP_SYSCALL: {
@@ -377,7 +375,7 @@ bool step_vm(VM *vm) {
     switch (syscall_id) {
     case SYSCALL_DEVICE_OPEN: {
       Device *dev;
-      u32 path_ptr, mode;
+      u32 path_ptr, mode, buffer_ptr;
       u8 path_reg, mode_reg, dest_reg;
       dest_reg = read_u8(vm, code, vm->pc);
       vm->pc++;
@@ -391,8 +389,14 @@ bool step_vm(VM *vm) {
       dev = find_device_by_path(vm, (const char *)&vm->memory[path_ptr + 4]);
       if (dev) {
         if (dev->ops->open) {
-          vm->flag = dev->ops->open(dev->data, mode);
-          frame->registers[dest_reg] = dev->handle;
+          /* return device plex to user */
+          buffer_ptr = vm->mp;
+          frame->registers[dest_reg] = buffer_ptr;
+          /* malloc size for device */
+          write_u32(vm, memory, buffer_ptr, dev->size);
+          vm->mp += (dev->size + 4);
+          /* set flag from user */
+          vm->flag = dev->ops->open(dev->data, mode, dev->handle, &vm->memory[buffer_ptr + 4], dev->size);
         } else {
           vm->flag = 1; /* success, no open needed */
         }
diff --git a/test/paint-bw.asm.lisp b/test/paint-bw.asm.lisp
index ae6a87b..59edba5 100644
--- a/test/paint-bw.asm.lisp
+++ b/test/paint-bw.asm.lisp
@@ -4,25 +4,27 @@
     ; use load immediate because it is a pointer to a string, not a value
     (load-immediate $0 &screen-namespace)
     (load-immediate $11 0)
-    (syscall OPEN $0 $0 $11)
+    (syscall OPEN $18 $0 $11) ; open(out Plex screen, in namespace, in flags)
+    (get $0 $18) ; load handle (offset 0)
 
-    (load-immediate $16 1) ; device info call
-    (load-immediate $17 16) ; sizeof screen device info
-    (malloc $18 $17)
-    (syscall IOCTL $0 $16 $18)
-    (load-immediate $1 12) ; offset for width
+    ; open mouse
+    (load-immediate $16 &mouse-namespace)
+    (syscall OPEN $15 $16 0)
+    (get $16 $15) ; load handle (offset 0)
+
+    (load-immediate $1 4) ; offset for width
     (add-nat $19 $18 $1)
     (get $20 $19) ; load width
+
     (load-immediate $1 8) ; offset for size
     (add-nat $19 $18 $1)
-    (get $22 $19) ; load size    
-    (malloc $21 $22) ; malloc frame buffer
+    (get $22 $19) ; load size   
 
-    (load-immediate $16 &mouse-namespace)
-	  (load-immediate $3 12) ; malloc sizeof mouse data
-	  (malloc $4 $3)
-    (syscall OPEN $16 $16 $4)
+    (load-immediate $1 12) ; offset for screen buffer
+    (add-nat $19 $18 $1)
+    (get $21 $19)
 
+    ; outline_swatch(screen, BLACK, 1, 1);
     (push $21)
     (push $20)
     (load $1 &BLACK)
@@ -33,6 +35,7 @@
     (push $13)
     (call &draw-outlined-swatch)
 
+    ; outline_swatch(screen, WHITE, 1, 1);
     (push $21)
     (push $20)
     (load $1 &WHITE)
@@ -45,7 +48,6 @@
     
     (syscall WRITE $0 $21 $22)
 
-
     (label draw-loop
       ; load mouse click data
 	  	(syscall READ $16 $2 $3 $4)
@@ -53,8 +55,6 @@
       (add-nat $6 $5 $2)
       (get-8 $9 $6) ; load btn1 pressed
 
-      (load-immediate $14 20) ; box size
-
       (jump-eq-nat &draw-loop $9 $11)
 
       (load-immediate $5 4) ; offset for x
@@ -63,9 +63,8 @@
       (load-immediate $5 8) ; offset for y
       (add-nat $6 $5 $2)
       (get $8 $6) ; load y
-      (load-immediate $5 13) ; offset for btn2
-      (add-nat $6 $5 $2)
-      (get-8 $10 $6) ; load btn2 pressed
+
+      (load-immediate $14 20) ; box size
 
       ; first row
       (push $21)
@@ -120,7 +119,7 @@
       (push $1)
       (call &draw-box)
 
-      (jump-eq-nat &draw-loop $10 $11))
+      (jump &draw-loop))
 
     ; Flush and halt
     (halt))
@@ -147,7 +146,8 @@
     (jump-lt-int &fail $1 $3)
     (jump-gt-int &fail $1 $7)
     ; If btn1 is pressed (==1), set color
-    (jump-eq-int &fail $12 1)
+    (load-immediate $8 1)
+    (jump-eq-int &fail $12 $8)
     (load-immediate $10 &SELECTED-COLOR)
     (store-8 $10 $11)
 
diff --git a/test/paint.asm.lisp b/test/paint.asm.lisp
index 43d22ae..3357aff 100644
--- a/test/paint.asm.lisp
+++ b/test/paint.asm.lisp
@@ -239,7 +239,7 @@
       (jump-eq-nat &draw-loop $9 $11)
 
       (load $22 &SELECTED-COLOR) ; color
-      (load-immediate $1 5) ; size of brush
+      (load-immediate $1 3) ; size of brush
 
       (push $21) ;base
       (push $20) ;width