diff --git a/hw/pc98kbd.c b/hw/pc98kbd.c
new file mode 100644
index 0000000..04e1fa5
--- /dev/null
+++ b/hw/pc98kbd.c
@@ -0,0 +1,395 @@
+/*
+ * QEMU NEC PC-9821 keyboard
+ *
+ * Copyright (c) 2009 TAKEDA, toshiya
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "hw.h"
+#include "pc.h"
+#include "isa.h"
+#include "qdev.h"
+#include "console.h"
+#include "qemu-timer.h"
+
+#define SIO_BUFFER_SIZE 256
+#define SIO_RECV_DELAY 8
+
+enum {
+    SIO_STAT_TXRDY  = 0x01,
+    SIO_STAT_RXRDY  = 0x02,
+    SIO_STAT_TXE    = 0x04,
+    SIO_STAT_PE     = 0x08,
+    SIO_STAT_OE     = 0x10,
+    SIO_STAT_FE     = 0x20,
+    SIO_STAT_SYNDET = 0x40,
+    SIO_STAT_DSR    = 0x80,
+};
+
+enum {
+    SIO_MODE_CLEAR,
+    SIO_MODE_SYNC,
+    SIO_MODE_ASYNC,
+    SIO_MODE_SYNC1,
+    SIO_MODE_SYNC2,
+};
+
+enum {
+    KBD_LOCK_NUMLK = 1,
+    KBD_LOCK_CAPS  = 4,
+    KBD_LOCK_KANA  = 8,
+    KBD_LOCK_MASK  = (1 | 4 | 8),
+};
+
+/*
+    END -> HELP
+    F11 -> STOP
+    F12 -> COPY
+*/
+
+static const uint8_t kbd_table[128] = {
+    0xff, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
+    0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0e, 0x0f,
+    0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+    0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x74, 0x1d, 0x1e,
+    0x1f, 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26,
+    0x27, 0xff, 0x70, 0x28, 0x29, 0x2a, 0x2b, 0x2c,
+    0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x70, 0xff,
+    0x70, 0x34, 0xff, 0x62, 0x63, 0x64, 0x65, 0x66,
+    0x67, 0x68, 0x69, 0x6a, 0x6b, 0xff, 0xff, 0x3e,
+    0x3a, 0x36, 0xff, 0x3b, 0xff, 0x3c, 0xff, 0x3f,
+    0x3d, 0x37, 0x38, 0x39, 0xff, 0xff, 0xff, 0x60,
+    0x61, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0x33, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0x35, 0xff, 0x51, 0xff, 0x0d, 0xff, 0xff,
+};
+
+struct KeyBoardState {
+    /* keyboard */
+    uint8_t lock;
+    uint8_t pressed[128];
+
+    /* sio */
+    uint8_t mode;
+    uint8_t status;
+    uint8_t rxen;
+    uint8_t txen;
+    uint8_t recv_data;
+    uint8_t recv_buf[SIO_BUFFER_SIZE];
+    int recv_count;
+    int recv_read;
+    int recv_write;
+    uint8_t send_buf[2];
+    int send_count;
+
+    QEMUTimer *sio_timer;
+    qemu_irq irq;
+};
+
+typedef struct ISAKeyBoardState {
+    ISADevice dev;
+    uint32_t isairq;
+    struct KeyBoardState state;
+} ISAKeyBoardState;
+
+typedef struct KeyBoardState KeyBoardState;
+
+/* keyboard */
+
+static void kbd_recv(void *opaque, uint8_t value)
+{
+    KeyBoardState *s = opaque;
+
+    if (s->recv_count < SIO_BUFFER_SIZE) {
+        s->recv_buf[(s->recv_write++) & (SIO_BUFFER_SIZE - 1)] = value;
+        s->recv_count++;
+        if (s->recv_count == 1) {
+            qemu_mod_timer(s->sio_timer, qemu_get_clock(rt_clock) +
+                           SIO_RECV_DELAY);
+        }
+    }
+}
+
+static void kbd_send(void *opaque, uint8_t value)
+{
+    KeyBoardState *s = opaque;
+
+    s->send_buf[(s->send_count++) & 1] = value;
+
+    switch (s->send_buf[0]) {
+    case 0x95:
+    case 0x9c:
+        kbd_recv(s, 0xfa);
+        if (s->send_count == 2) {
+            s->send_count = 0;
+        }
+        break;
+    case 0x96:
+        kbd_recv(s, 0xfa);
+        kbd_recv(s, 0xa0);
+        kbd_recv(s, 0x85);/*0x86*/
+        s->send_count = 0;
+        break;
+    case 0x99:
+        kbd_recv(s, 0xfa);
+        kbd_recv(s, 0xfb);
+        s->send_count = 0;
+        break;
+    case 0x9d:
+        kbd_recv(s, 0xfa);
+        if (s->send_count == 2) {
+            if (s->send_buf[1] == 0x60) {
+                kbd_recv(s, 0x70 | (s->lock & KBD_LOCK_MASK));
+            } else {
+                s->lock = value;
+            }
+            s->send_count = 0;
+        }
+        break;
+    case 0x9f:
+        kbd_recv(s, 0xfa);
+        kbd_recv(s, 0xa0);
+        kbd_recv(s, 0x80);
+        s->send_count = 0;
+        break;
+    default:
+        kbd_recv(s, 0xfc);
+        s->send_count = 0;
+        break;
+    }
+}
+
+static void kbd_event_handler(void *opaque, int keycode)
+{
+    KeyBoardState *s = opaque;
+
+    if (keycode & 0x80) {
+        /* key released */
+        if ((keycode = kbd_table[keycode & 0x7f]) != 0xff) {
+            if(s->pressed[keycode]) {
+                kbd_recv(s, keycode | 0x80);
+            }
+            s->pressed[keycode] = 0;
+        }
+    } else {
+        /* key pressed */
+        if (keycode == 0x3a) {
+            s->lock ^= KBD_LOCK_CAPS;
+            if (s->lock & KBD_LOCK_CAPS) {
+                kbd_recv(s, 0x71);
+            } else {
+                kbd_recv(s, 0x71 | 0x80);
+            }
+        } else if (keycode == 0x70) {
+            s->lock ^= KBD_LOCK_KANA;
+            if (s->lock & KBD_LOCK_KANA) {
+                kbd_recv(s, 0x72);
+            } else {
+                kbd_recv(s, 0x72 | 0x80);
+            }
+        } else if ((keycode = kbd_table[keycode]) != 0xff) {
+            if(s->pressed[keycode]) {
+                kbd_recv(s, keycode | 0x80);
+            }
+            kbd_recv(s, keycode);
+            s->pressed[keycode] = 1;
+        }
+    }
+}
+
+/* sio */
+
+static void sio_data_write(void *opaque, uint32_t addr, uint32_t value)
+{
+    KeyBoardState *s = opaque;
+
+    if (s->status & SIO_STAT_TXRDY) {
+        s->status &= ~SIO_STAT_TXE;
+        kbd_send(s, value);
+    }
+}
+
+static uint32_t sio_data_read(void *opaque, uint32_t addr)
+{
+    KeyBoardState *s = opaque;
+
+    s->status &= ~SIO_STAT_RXRDY;
+    qemu_set_irq(s->irq, 0);
+    return s->recv_data;
+}
+
+static void sio_cmd_write(void *opaque, uint32_t addr, uint32_t value)
+{
+    KeyBoardState *s = opaque;
+
+    switch(s->mode) {
+    case SIO_MODE_CLEAR:
+        if(value & 3) {
+            s->mode = SIO_MODE_ASYNC;
+        } else if(value & 0x80) {
+            s->mode = SIO_MODE_SYNC2;	/* 1char */
+        } else {
+            s->mode = SIO_MODE_SYNC1;	/* 2chars */
+        }
+        break;
+    case SIO_MODE_SYNC1:
+        s->mode = SIO_MODE_SYNC2;
+        break;
+    case SIO_MODE_SYNC2:
+        s->mode = SIO_MODE_SYNC;
+        break;
+    case SIO_MODE_ASYNC:
+    case SIO_MODE_SYNC:
+        if(value & 0x40) {
+            s->mode = SIO_MODE_CLEAR;
+            break;
+        }
+        if(value & 0x10) {
+            s->status &= ~(SIO_STAT_PE | SIO_STAT_OE | SIO_STAT_FE);
+        }
+        s->rxen = value & 4;
+        s->txen = value & 1;
+        break;
+    }
+}
+
+static uint32_t sio_status_read(void *opaque, uint32_t addr)
+{
+    KeyBoardState *s = opaque;
+    uint8_t value;
+
+    value = s->status;
+    if (s->txen) {
+        s->status |= SIO_STAT_TXE;
+    }
+    return value;
+}
+
+static void sio_timer_handler(void *opaque)
+{
+    KeyBoardState *s = opaque;
+
+    if (s->recv_count > 0) {
+        uint8_t value = s->recv_buf[(s->recv_read++) & 0xff];
+        s->recv_count--;
+        if (s->rxen) {
+            if (!(s->status & SIO_STAT_RXRDY)) {
+                s->status |= SIO_STAT_RXRDY;
+                s->recv_data = value;
+                qemu_set_irq(s->irq, 1);
+            } else {
+                /* time out */
+                s->status |= SIO_STAT_OE;
+            }
+        }
+        if (s->recv_count > 0) {
+            qemu_mod_timer(s->sio_timer, qemu_get_clock(rt_clock) +
+                           SIO_RECV_DELAY);
+        }
+    }
+}
+
+/* interface */
+
+static void pc98_kbd_reset(void *opaque)
+{
+    KeyBoardState *s = opaque;
+
+    s->lock = 0;
+    memset(s->pressed, 0, 128);
+
+    s->mode = SIO_MODE_CLEAR;
+    s->status = (SIO_STAT_TXRDY | SIO_STAT_TXE);
+    s->txen = s->rxen = 0;
+    s->recv_data = 0xff;
+    s->recv_count = s->recv_read = s->recv_write = 0;
+    s->send_count = 0;
+}
+
+static int pc98_kbd_pre_load(void *opaque)
+{
+    pc98_kbd_reset(opaque);
+    return 0;
+}
+
+static const VMStateDescription vmstate_kbd = {
+    .name = "pc98-kbd",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .pre_load = pc98_kbd_pre_load,
+    .fields      = (VMStateField []) {
+        VMSTATE_UINT8(lock, KeyBoardState),
+        VMSTATE_UINT8(mode, KeyBoardState),
+        VMSTATE_UINT8(status, KeyBoardState),
+        VMSTATE_UINT8(rxen, KeyBoardState),
+        VMSTATE_UINT8(txen, KeyBoardState),
+        VMSTATE_UINT8(recv_data, KeyBoardState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static int pc98_kbd_initfn(ISADevice *dev)
+{
+    ISAKeyBoardState *isa = DO_UPCAST(ISAKeyBoardState, dev, dev);
+    KeyBoardState *s = &isa->state;
+
+    register_ioport_write(0x41, 1, 1, sio_data_write, s);
+    register_ioport_read(0x41, 1, 1, sio_data_read, s);
+    register_ioport_write(0x43, 1, 1, sio_cmd_write, s);
+    register_ioport_read(0x43, 1, 1, sio_status_read, s);
+
+    isa_init_irq(dev, &s->irq, isa->isairq);
+
+    s->sio_timer = qemu_new_timer(rt_clock, sio_timer_handler, s);
+    qemu_add_kbd_event_handler(kbd_event_handler, s);
+
+    vmstate_register(-1, &vmstate_kbd, s);
+    pc98_kbd_reset(s);
+    qemu_register_reset(pc98_kbd_reset, s);
+
+    return 0;
+}
+
+void pc98_kbd_init(void)
+{
+    ISADevice *dev;
+
+    dev = isa_create("pc98-kbd");
+    qdev_init_nofail(&dev->qdev);
+}
+
+static ISADeviceInfo pc98_kbd_info = {
+    .qdev.name  = "pc98-kbd",
+    .qdev.size  = sizeof(ISAKeyBoardState),
+    .init       = pc98_kbd_initfn,
+    .qdev.props = (Property[]) {
+        DEFINE_PROP_UINT32("irq", ISAKeyBoardState, isairq, 1),
+        DEFINE_PROP_END_OF_LIST(),
+    },
+};
+
+static void pc98_kbd_register_devices(void)
+{
+    isa_qdev_register(&pc98_kbd_info);
+}
+
+device_init(pc98_kbd_register_devices)
