diff --git a/Makefile b/Makefile
index 7acfb93..b7be8d7 100644
--- a/Makefile
+++ b/Makefile
@@ -31,7 +31,7 @@ NESE_SRC_SRCS = f6502.c f6502_opcodes.c
 NESE_SRC_SRCS += nese.c nes.c cart.c mapper.c
 NESE_SRC_SRCS += ppu.c
 NESE_SRC_SRCS += $(OS)/port.c
-NESE_MAP_SRCS = $(notdir $(wildcard $(MAPDIR)/*))
+NESE_MAP_SRCS = $(notdir $(wildcard $(MAPDIR)/*.c))
 
 NESE_DEBUG = CART
 
diff --git a/src/input.h b/src/input.h
new file mode 100644
index 0000000..3d223a7
--- /dev/null
+++ b/src/input.h
@@ -0,0 +1,29 @@
+#ifndef NESE_INPUT_H_
+#define NESE_INPUT_H_
+
+
+#define nes_controller_bus_mask (0b11111000)
+
+
+typedef enum {
+    Button_A = 0,
+    Button_B,
+    Button_Select,
+    Button_Start,
+    Button_Up,
+    Button_Down,
+    Button_Left,
+    Button_Right,
+} nes_Input_Button;
+
+typedef struct {
+    uint8_t buttons;
+    int8_t shift;
+} nes_Gamepad;
+
+typedef struct {
+    nes_Gamepad gamepads[2];
+} nes_Input;
+
+
+#endif // NESE_INPUT_H_
diff --git a/src/linux/port.c b/src/linux/port.c
index 368b8d9..79c0da1 100644
--- a/src/linux/port.c
+++ b/src/linux/port.c
@@ -1,6 +1,7 @@
 #include <errno.h>
 #include <stdio.h>
 
+#include <time.h>
 #include <sys/mman.h>
 
 #include "nese.h"
@@ -24,6 +25,37 @@ int nese_unmap_file(void* addr, int size) {
     return munmap(addr, size);
 }
 
+int nese_frame_ready() {
+/*
+    static int frame = 0;
+    static int ignore = 1;
+    static struct timespec t_last = {0};
+    struct timespec t_now = {0};
+
+    ++frame;
+    clock_gettime(CLOCK_MONOTONIC, &t_now);
+
+    if (t_now.tv_sec > t_last.tv_sec) {
+        if (!ignore) printf("%d\n", frame);
+        frame = 0;
+        ignore = 0;
+    }
+
+    t_last = t_now;
+*/
+
+    // TODO: Render frame
+    // TODO: Time sync
+    // TODO: Handle quit signal
+    // TODO: Perform menu actions
+    return 0;
+}
+
+int nese_update_input(nes_Input* input) {
+    // TODO: Populate the gamepad states
+    return 0;
+}
+
 
 static nes sys = {0};
 
diff --git a/src/nes.c b/src/nes.c
index 758108f..b88daa4 100644
--- a/src/nes.c
+++ b/src/nes.c
@@ -1,6 +1,7 @@
 #include <stddef.h>
 
 #include "nes.h"
+#include "port.h"
 
 
 void nes_init(nes* sys) {
@@ -11,19 +12,54 @@ void nes_done(nes* sys) {
     // TODO: deallocate RAM, etc.
 }
 
+static int nes_vsync(nes* sys) {
+    int status = 0;
+
+    // TODO: PPU Set VBlank flag
+    // TODO: APU Sync
+    // TODO: APU Frame IRQ
+
+    nes_Memory* mem = &sys->core.memory;
+    if (0 == status && NULL != mem->mapper.vsync) {
+        mem->mapper.vsync(&mem->mapper);
+        status = nese_update_input(&sys->input);
+    }
+
+    // TODO: NMI
+
+    return status;
+}
+
 static int nes_hsync(nes* sys) {
+    int status = 0;
+
     // TODO: APU sync
 
+    // TODO: PPU Update H Bytes & Select Nametable
     // TODO: PPU draw line if visible
-
     // TODO: PPU update regs
 
-    // TODO: Increment scanline
+    sys->ppu.scanline++;
+    if (nes_ppu_frame_end_line == sys->ppu.scanline) {
+        sys->ppu.scanline = 0;
+    }
 
-    // TODO: Scanline region updates
-    // TODO: nese_vsync called in nes_vsync
+    switch (sys->ppu.scanline) {
+    case nes_ppu_prerender_line:
+        // TODO: Reset PPU Status
+        // TODO: Get Sprite 0 Hit
+        break;
 
-    return 0;
+    case nes_ppu_postrender_line:
+        status = nese_frame_ready();
+        break;
+
+    case nes_ppu_vblank_line:
+        status = nes_vsync(sys);
+        break;
+    }
+
+    return status;
 }
 
 int nes_loop(nes* sys) {
@@ -37,9 +73,6 @@ int nes_loop(nes* sys) {
         dot += 3 * f6502_step(&sys->core, cpu_cycles);
         dot -= nes_ppu_scanline_dots;
         // TODO: Validate dot >= 0?
-
-        // TODO: Frame IRQ
-
         nes_Memory* mem = &sys->core.memory;
         if (NULL != mem->mapper.hsync) {
             mem->mapper.hsync(&mem->mapper);
diff --git a/src/nes.h b/src/nes.h
index d06d130..2c3b333 100644
--- a/src/nes.h
+++ b/src/nes.h
@@ -2,15 +2,18 @@
 #define NES_H_
 
 #include "ines.h"
+#include "input.h"
 #include "f6502.h"
+#include "ppu.h"
 
 
 typedef struct {
     const ines_Header* cart_header;
     f6502_Core core;
+    nes_PPU ppu;
     // TODO: PPU
     // TODO: APU
-    // TODO: Input
+    nes_Input input;
 } nes;
 
 void nes_init(nes*);
diff --git a/src/port.h b/src/port.h
index 9e611bd..aa0f2e5 100644
--- a/src/port.h
+++ b/src/port.h
@@ -1,9 +1,16 @@
 #ifndef NESE_PORT_H_
 #define NESE_PORT_H_
 
+#include <stdio.h>
+
+#include "input.h"
+
 
 void* nese_map_file(FILE* file, int size);
 int nese_unmap_file(void* addr, int size);
 
+int nese_frame_ready();
+int nese_update_input(nes_Input*);
+
 
 #endif // NESE_PORT_H_
diff --git a/src/ppu.h b/src/ppu.h
index 8df7505..1d1b2d4 100644
--- a/src/ppu.h
+++ b/src/ppu.h
@@ -5,6 +5,7 @@
 
 
 #define nes_ppu_scanline_dots   (341U)
+#define nes_ppu_prerender_line  (0U)
 #define nes_ppu_visible_line    (1U)
 #define nes_ppu_postrender_line (241U)
 #define nes_ppu_vblank_line     (242U)
@@ -53,4 +54,9 @@ void nes_PPU_set_mirroring(nes_PPU_Memory* mem,
                            nes_Nametable_Mirroring mirror);
 
 
+typedef struct {
+    int scanline;
+} nes_PPU;
+
+
 #endif // NESE_PPU_H_