diff --git a/src/io_device.cpp b/src/io_device.cpp
index 34df0dd..1772394 100644
--- a/src/io_device.cpp
+++ b/src/io_device.cpp
@@ -15,60 +15,57 @@ namespace {
 
 bool sdl_is_initialized = false;
 
-struct Char {
-    explicit constexpr Char(char ch, uint64_t data)
-        : ch(ch)
-        , data(data)
-    {
+constexpr uint64_t char_data(uint8_t ch)
+{
+    switch (ch) {
+        // clang-format off
+        case ' ': return 0x0000000000000000;
+
+        case '0': return 0x003C666E7666663C;
+        case '1': return 0x001838181818183C;
+        case '2': return 0x003C66060C18307E;
+        case '3': return 0x003C66060C06663C;
+        case '4': return 0x000C1C3C6C7E0C0C;
+
+        case 'A': return 0x00187E66667E6666;
+        case 'B': return 0x00787E667C667E7C;
+        case 'C': return 0x003C7E6060607E3C;
+        case 'D': return 0x007C7E6666667E7C;
+        case 'E': return 0x007E7E607E607E7E;
+        case 'F': return 0x007E7E6078786060;
+        case 'G': return 0x007E7E606E667E7E;
+        case 'H': return 0x0066667E7E666666;
+        case 'I': return 0x007E7E1818187E7E;
+        case 'J': return 0x007E7E0606667E3C;
+        case 'K': return 0x0066666E7C7C6E66;
+        case 'L': return 0x0060606060607E7E;
+        case 'M': return 0x00E7FFDBC3C3C3C3;
+        case 'N': return 0x0066767E6E666666;
+        case 'O': return 0x003C66666666663C;
+        case 'P': return 0x007C7C667E7C6060;
+        case 'Q': return 0x003C7E66666E7E3F;
+        case 'R': return 0x007C7E667E7C6C66;
+        case 'S': return 0x003C66603C06663C;
+        case 'T': return 0x007E7E1818181818;
+        case 'U': return 0x0066666666667E3C;
+        case 'V': return 0x00666666667E3C18;
+        case 'W': return 0x00C3C3C3DBDBFFE7;
+        case 'X': return 0x0066663C3C666666;
+        case 'Y': return 0x0066663C18181818;
+        case 'Z': return 0x007E7E0C18307E7E;
+        default:  return 0x55AA55AA55AA55AA;
+        // clang-format on
     }
-
-    auto to_u64() const -> uint64_t
-    {
-        return data;
-    }
-
-    char ch;
-    uint64_t data;
-};
-
-constexpr auto charset = std::array {
-    Char(' ', 0x0000000000000000),
-    Char('A', 0x66667E66667E1800),
-    Char('B', 0x7C7E667C667E7800),
-    Char('C', 0x3C7E6060607E3C00),
-    Char('D', 0x7C7E6666667E7C00),
-    Char('E', 0x7E7E607E607E7E00),
-    Char('F', 0x60607878607E7E00),
-    Char('G', 0x7E7E666E607E7E00),
-    Char('H', 0x6666667E7E666600),
-    Char('I', 0x7E7E1818187E7E00),
-    Char('J', 0x3C7E6606067E7E00),
-    Char('K', 0x666E7C7C6E666600),
-    Char('L', 0x7E7E606060606000),
-    Char('M', 0xC3C3C3C3DBFFE700),
-    Char('N', 0x6666666E7E766600),
-    Char('O', 0x3C66666666663C00),
-    Char('P', 0x60607C7E667C7C00),
-    Char('Q', 0x3F7E6E66667E3C00),
-    Char('R', 0x666C7C7E667E7C00),
-    Char('S', 0x3C66063C60663C00),
-    Char('T', 0x18181818187E7E00),
-    Char('U', 0x3C7E666666666600),
-    Char('V', 0x183C7E6666666600),
-    Char('W', 0xE7FFDBDBC3C3C300),
-    Char('X', 0x6666663C3C666600),
-    Char('Y', 0x181818183C666600),
-    Char('Z', 0x7E7E30180C7E7E00),
 };
 
 }
 
-auto IoDevice::create(int ch_size, int ch_width, int ch_height)
+auto IoDevice::create()
     -> std::expected<std::unique_ptr<IoDevice>, std::string>
 {
-    auto profile = ScreenProfile(ch_size, ch_width, ch_height);
-    auto px_width= profile.px_width;
-    auto px_height = profile.px_height;
+    auto profile = ScreenProfile();
+    auto width = profile.width_raw_px();
+    auto height = profile.height_raw_px();
 
     if (!sdl_is_initialized) {
         if (SDL_Init(SDL_INIT_VIDEO) != 0) {
@@ -79,7 +76,7 @@ auto IoDevice::create(int ch_size, int ch_width, int ch_height)
     SDL_Window* window;
     SDL_Renderer* renderer;
 
-    if (SDL_CreateWindowAndRenderer(px_width, px_height, 0, &window, &renderer)
+    if (SDL_CreateWindowAndRenderer(width, height, 0, &window, &renderer)
         != 0) {
         return std::unexpected(SDL_GetError());
     }
@@ -87,8 +84,8 @@ auto IoDevice::create(int ch_size, int ch_width, int ch_height)
     SDL_Texture* texture = SDL_CreateTexture(renderer,
         SDL_PIXELFORMAT_RGBA32,
         SDL_TEXTUREACCESS_STREAMING,
-        px_width,
-        px_height);
+        width,
+        height);
 
     if (texture == nullptr) {
         return std::unexpected(SDL_GetError());
@@ -117,11 +114,6 @@ auto IoDevice::set_char(uint16_t offset, uint8_t value)
 {
     auto lock = std::lock_guard(mx);
 
-    auto it = std::find_if(charset.begin(), charset.end(), [&](Char ch) {
-        return ch.ch == value;
-    });
-    uint64_t char_data = it->to_u64();
-
     SDL_Color* buffer;
     int pitch;
     int res = SDL_LockTexture(m_texture, NULL, (void**)&buffer, &pitch);
@@ -129,29 +121,42 @@ auto IoDevice::set_char(uint16_t offset, uint8_t value)
         return std::unexpected(SDL_GetError());
     }
 
-    auto [ch_size, ch_width, ch_height, px_width, px_height] = m_profile;
-    std::println("ch_size = {}, ch_width = {}, ch_height = {}, px_width = {}, px_height = {}", ch_size, ch_width, ch_height, px_width, px_height);
+    constexpr auto white = SDL_Color { 0xff, 0xff, 0xff, 0xff };
+    constexpr auto black = SDL_Color { 0x00, 0x00, 0x00, 0xff };
 
-    for (int ch_y = 0; ch_y < 8; ++ch_y) {
-        for (int ch_x = 0; ch_x < 8; ++ch_x) {
-            bool ch
-                = char_data >> (ch_y * 8 + (8 - ch_x - 1))
-                & 1;
+    int ch_size = m_profile.ch_size_px();
+    int px_size = m_profile.px_size_raw_px();
+    int raw_width = m_profile.width_raw_px();
+    int width_ch = m_profile.width_ch();
 
-            for (int px_y = 0; px_y < ch_size; ++px_y) {
-                for (int px_x = 0; px_x < ch_size; ++px_x) {
+    auto set_pixel = [&](int x, int y, bool ch) {
+        int raw_base_x = x * px_size;
+        int raw_base_y = y * px_size;
 
-                    int x = (offset % 4 * ch_size + ch_x) * 4
-                        + px_x;
-                    int y = (offset / 4 * ch_size + ch_y) * 4
-                        + px_y;
+        for (int raw_px_y = 0; raw_px_y < px_size; ++raw_px_y) {
+            for (int raw_px_x = 0; raw_px_x < px_size; ++raw_px_x) {
 
-                    buffer[y * px_width + x] = ch
-                        ? SDL_Color { 0xff, 0xff, 0xff, 0xff }
-                        : SDL_Color { 0x00, 0x00, 0x00, 0xff };
-                }
+                int x = raw_base_x + raw_px_x;
+                int y = raw_base_y + raw_px_y;
+
+                buffer[y * raw_width + x] = ch ? white : black;
             }
         }
+    };
+
+    uint64_t char_data = ::char_data(value);
+
+    int base_x = offset % width_ch * ch_size;
+    int base_y = offset / width_ch * ch_size;
+
+    for (int px_y = 0; px_y < ch_size; ++px_y) {
+        uint8_t row = char_data >> (7 - px_y) * ch_size & 0xff;
+
+        for (int px_x = 0; px_x < ch_size; ++px_x) {
+            bool ch = row >> (7 - px_x) & 1;
+
+            set_pixel(base_x + px_x, base_y + px_y, ch);
+        }
     }
 
     SDL_UnlockTexture(m_texture);
@@ -161,3 +166,33 @@ auto IoDevice::set_char(uint16_t offset, uint8_t value)
 
     return {};
 }
+
+auto IoDevice::poll_event()
+    -> std::unique_ptr<IoEvent>
+{
+    std::lock_guard lock(mx);
+
+    SDL_Event event;
+    if (SDL_PollEvent(&event)) {
+        switch (event.type) {
+            case SDL_QUIT:
+                return std::make_unique<IoEvent>(IoEvent::Type::Quit, IoEvent::Quit{});
+            case SDL_KEYDOWN:
+                if (event.key.keysym.sym == SDLK_ESCAPE) {
+                    return std::make_unique<IoEvent>(IoEvent::Type::Quit, IoEvent::Quit{});
+                }
+                return std::make_unique<IoEvent>(
+                    IoEvent::Type::KeyPress,
+                    IoEvent::KeyPress { static_cast<uint16_t>(event.key.keysym.scancode) });
+            case SDL_KEYUP:
+                return std::make_unique<IoEvent>(
+                    IoEvent::Type::KeyRelease,
+                    IoEvent::KeyRelease { static_cast<uint16_t>(event.key.keysym.scancode) });
+            // default:
+                // std::println(stderr, "warning: unhandled event '{}'", event.type);
+        }
+    }
+
+    return {};
+}
+
diff --git a/src/io_device.hpp b/src/io_device.hpp
index 84bebe9..9b55670 100644
--- a/src/io_device.hpp
+++ b/src/io_device.hpp
@@ -5,6 +5,7 @@
 #include <memory>
 #include <mutex>
 #include <string>
+#include <variant>
 
 struct SDL_Window;
 struct SDL_Renderer;
@@ -12,26 +13,61 @@ struct SDL_Texture;
 
 namespace vc5 {
 
-struct ScreenProfile {
-    explicit ScreenProfile(int ch_size, int ch_width, int ch_height)
-        : ch_size(ch_size)
-        , ch_width(ch_width)
-        , ch_height(ch_height)
-        , px_width(ch_size * 8 * ch_width)
-        , px_height(ch_size * 8 * ch_height)
-    {
-    }
+namespace events {
 
-    int ch_size;
-    int ch_width;
-    int ch_height;
-    int px_width;
-    int px_height;
+
+}
+
+class IoEvent {
+public:
+    enum class Type {
+        Quit,
+        KeyPress,
+        KeyRelease,
+    };
+
+    struct Quit{};
+
+    struct KeyPress{ uint16_t key; };
+
+    struct KeyRelease{ uint16_t key; };
+
+    using Data = std::variant<Quit, KeyPress, KeyRelease>;
+
+    explicit IoEvent(Type type, Data data)
+        : m_type(type)
+        , m_data(std::move(data))
+    {}
+
+    Type type() const { return m_type; }
+    auto as_quit() -> Quit& { return std::get<Quit>(m_data); }
+    auto as_key_press() -> KeyPress& { return std::get<KeyPress>(m_data); }
+    auto as_key_release() -> KeyRelease& { return std::get<KeyRelease>(m_data); }
+
+private:
+    Type m_type;
+    Data m_data;
+};
+
+struct ScreenProfile {
+    int m_px_size_raw_px = 4;
+    int m_ch_size_px = 8;
+    int m_width_ch = 40;
+    int m_height_ch = 24;
+
+    constexpr int px_size_raw_px() const { return m_px_size_raw_px; }
+    constexpr int ch_size_px() const { return m_ch_size_px; }
+
+    constexpr int width_ch() const { return m_width_ch; }
+    constexpr int height_ch() const { return m_height_ch; }
+
+    constexpr int width_raw_px() const { return px_size_raw_px() * ch_size_px() * width_ch(); }
+    constexpr int height_raw_px() const { return px_size_raw_px() * ch_size_px() * height_ch(); }
 };
 
 class IoDevice {
 public:
-    static auto create(int ch_size, int ch_width, int ch_height)
+    static auto create()
         -> std::expected<std::unique_ptr<IoDevice>, std::string>;
 
     explicit IoDevice(ScreenProfile profile,
@@ -49,6 +85,8 @@ public:
     auto set_char(uint16_t offset, uint8_t value)
         -> std::expected<void, std::string>;
 
+    auto poll_event() -> std::unique_ptr<IoEvent>;
+
 private:
     std::mutex mx;
 
diff --git a/src/main.cpp b/src/main.cpp
index c08eef4..142f00c 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -8,6 +8,8 @@
 #include <cstdlib>
 #include <thread>
 #include <chrono>
+#include <iostream>
+#include <string>
 
 
 using namespace std::chrono_literals;
@@ -17,10 +19,14 @@ using R = Reg;
 
 int main()
 {
-    auto device = IoDevice::create(4, 40, 24).value();
-    device->set_char(0, 'A').value();
+    auto device = IoDevice::create().value();
 
-    std::this_thread::sleep_for(1s);
+    auto message = std::string("A-0123456789");
+    uint16_t offset = 0;
+    for (auto ch : message) {
+        device->set_char(offset, static_cast<uint8_t>(ch)).value();
+        offset += 1;
+    }
 
     constexpr R r0 = R::R0;
     constexpr R r1 = R::R1;
@@ -76,6 +82,15 @@ int main()
     for (uint16_t i = 0; i < 32; i += 2) {
         std::println("{: 4x}\t{}", i, vm.word(i));
     }
+
+
+    while (true) {
+        auto event = device->poll_event();
+
+        if (event && event->type() == IoEvent::Type::Quit) {
+            break;
+        }
+    }
 }
 
 extern "C" const char* __asan_default_options(void)
diff --git a/src/vm.cpp b/src/vm.cpp
index 2337ca0..9eeed06 100644
--- a/src/vm.cpp
+++ b/src/vm.cpp
@@ -47,7 +47,7 @@ int VM::run_instruction()
         ip,
         ins.operator uint16_t(),
         op_str(op),
-        m_regs[reg_id(Reg::R0)]);
+        m_regs[reg_value(Reg::R0)]);
 
     switch (op) {
         case Op::Nop:
@@ -80,7 +80,7 @@ int VM::run_instruction()
 
             if ((addr & 0b1) != 0) {
                 std::println(stderr, "error: invalid address alignment");
-                *m_rfl |= 1 << flag_id(Flag::Err);
+                *m_rfl |= 1 << flag_value(Flag::Err);
                 goto halt_execution;
             }
 
@@ -98,7 +98,7 @@ int VM::run_instruction()
 
             if ((addr & 0b1) != 0) {
                 std::println(stderr, "error: invalid address alignment");
-                *m_rfl |= 1 << flag_id(Flag::Err);
+                *m_rfl |= 1 << flag_value(Flag::Err);
                 goto halt_execution;
             }
 
@@ -127,19 +127,19 @@ int VM::run_instruction()
             auto op2 = ins.op2_or_imm();
 
             if (op1 == op2) {
-                *m_rfl |= 1u << flag_id(Flag::Eq);
+                *m_rfl |= 1u << flag_value(Flag::Eq);
             } else {
-                *m_rfl &= (uint16_t)~(1u << flag_id(Flag::Eq));
+                *m_rfl &= (uint16_t)~(1u << flag_value(Flag::Eq));
             }
             if (op1 < op2) {
-                *m_rfl |= 1u << flag_id(Flag::Be);
+                *m_rfl |= 1u << flag_value(Flag::Be);
             } else {
-                *m_rfl &= (uint16_t)~(1u << flag_id(Flag::Be));
+                *m_rfl &= (uint16_t)~(1u << flag_value(Flag::Be));
             }
             if ((int16_t)op1 < (int16_t)op2) {
-                *m_rfl |= 1u << flag_id(Flag::Lt);
+                *m_rfl |= 1u << flag_value(Flag::Lt);
             } else {
-                *m_rfl &= (uint16_t)~(1u << flag_id(Flag::Lt));
+                *m_rfl &= (uint16_t)~(1u << flag_value(Flag::Lt));
             }
             break;
         }
@@ -202,6 +202,15 @@ halt_execution:
     return 0;
 }
 
+uint16_t VM::eat()
+{
+    uint16_t ins = 0;
+    ins |= static_cast<uint16_t>(m_mem[*m_rip]) << 8;
+    ins |= m_mem[*m_rip + 1];
+    *m_rip += 2;
+    return ins;
+}
+
 const char* vc5::op_str(Op op)
 {
     switch (op) {
@@ -248,3 +257,4 @@ const char* vc5::op_str(Op op)
     }
     return ">.<";
 }
+
diff --git a/src/vm.hpp b/src/vm.hpp
index 8e92316..a7cda64 100644
--- a/src/vm.hpp
+++ b/src/vm.hpp
@@ -47,6 +47,11 @@ enum class Reg : uint16_t {
     Rip = 9,
 };
 
+constexpr uint16_t reg_value(Reg reg)
+{
+    return std::to_underlying(reg);
+}
+
 enum class Flag : uint16_t {
     Zero = 0,
     Eq = 1,
@@ -55,7 +60,10 @@ enum class Flag : uint16_t {
     Err = 4,
 };
 
-struct Ins;
+constexpr uint16_t flag_value(Flag flag)
+{
+    return std::to_underlying(flag);
+}
 
 class VM {
 public:
@@ -68,7 +76,7 @@ public:
 
     uint16_t reg(Reg reg) const
     {
-        return m_regs[reg_id(reg)];
+        return m_regs[reg_value(reg)];
     };
 
     uint16_t word(uint16_t addr) const
@@ -78,6 +86,7 @@ public:
         value |= m_mem[addr + 1];
         return value;
     }
+
     uint8_t byte(uint16_t addr) const
     {
         return m_mem[addr];
@@ -86,32 +95,14 @@ public:
 private:
     friend struct Ins;
 
-    static constexpr uint16_t reg_id(Reg reg)
-    {
-        return std::to_underlying(reg);
-    }
-
-    static constexpr uint16_t flag_id(Flag flag)
-    {
-        return std::to_underlying(flag);
-    }
-
     int run_instruction();
-
-    inline uint16_t eat()
-    {
-        uint16_t ins = 0;
-        ins |= static_cast<uint16_t>(m_mem[*m_rip]) << 8;
-        ins |= m_mem[*m_rip + 1];
-        *m_rip += 2;
-        return ins;
-    }
+    uint16_t eat();
 
     std::array<uint8_t, 65536> m_mem = {};
     std::array<uint16_t, 10> m_regs = {};
 
-    uint16_t* m_rfl = &m_regs[reg_id(Reg::Rfl)];
-    uint16_t* m_rip = &m_regs[reg_id(Reg::Rip)];
+    uint16_t* m_rfl = &m_regs[reg_value(Reg::Rfl)];
+    uint16_t* m_rip = &m_regs[reg_value(Reg::Rip)];
 
     bool m_halted = false;
 };