diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8d7b3f6f0..aa687222a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -11,7 +11,7 @@
 # Authors: David Hrdlička, <hrdlickadavid@outlook.com>
 #
 #          Copyright 2020-2021 David Hrdlička.
-#          Copyright 2021-2024 Jasmine Iwanek.
+#          Copyright 2021-2025 Jasmine Iwanek.
 #
 
 cmake_minimum_required(VERSION 3.16)
diff --git a/CMakePresets.json b/CMakePresets.json
index d4af8e6cb..be6615088 100644
--- a/CMakePresets.json
+++ b/CMakePresets.json
@@ -55,6 +55,14 @@
             },
             "inherits": "base"
         },
+        {
+            "name": "ultra_debug",
+            "cacheVariables": {
+                "CMAKE_BUILD_TYPE": "UltraDebug",
+                "DEV_BRANCH": "ON"
+            },
+            "inherits": "base"
+        },
         {
             "name": "llvm-macos-aarch64.cmake",
             "displayName": "MacOS clang regular",
diff --git a/cmake/flags-gcc.cmake b/cmake/flags-gcc.cmake
index 885353b87..90eb52cd1 100644
--- a/cmake/flags-gcc.cmake
+++ b/cmake/flags-gcc.cmake
@@ -20,6 +20,8 @@ string(APPEND CMAKE_C_FLAGS_RELEASE_INIT        " -g0 -O3")
 string(APPEND CMAKE_CXX_FLAGS_RELEASE_INIT      " -g0 -O3")
 string(APPEND CMAKE_C_FLAGS_DEBUG_INIT          " -ggdb -Og")
 string(APPEND CMAKE_CXX_FLAGS_DEBUG_INIT        " -ggdb -Og")
+string(APPEND CMAKE_C_FLAGS_ULTRADEBUG_INIT     " -O0 -ggdb -g3")
+string(APPEND CMAKE_CXX_FLAGS_ULTRADEBUG_INIT   " -O0 -ggdb -g3")
 string(APPEND CMAKE_C_FLAGS_OPTIMIZED_INIT      " -march=native -mtune=native -O3 -ffp-contract=fast -flto")
 string(APPEND CMAKE_CXX_FLAGS_OPTIMIZED_INIT    " -march=native -mtune=native -O3 -ffp-contract=fast -flto")
 
@@ -28,7 +30,7 @@ foreach(LANG C;CXX)
     set(CMAKE_${LANG}_FLAGS "$ENV{${LANG}FLAGS} ${CMAKE_${LANG}_FLAGS_INIT}" CACHE STRING "Flags used by the ${LANG} compiler during all build types.")
     mark_as_advanced(CMAKE_${LANG}_FLAGS)
 
-    foreach(CONFIG RELEASE;DEBUG;OPTIMIZED)
+    foreach(CONFIG RELEASE;DEBUG;ULTRADEBUG;OPTIMIZED)
         set(CMAKE_${LANG}_FLAGS_${CONFIG} "${CMAKE_${LANG}_FLAGS_${CONFIG}_INIT}" CACHE STRING "Flags used by the ${LANG} compiler during ${CONFIG} builds.")
         mark_as_advanced(CMAKE_${LANG}_FLAGS_${CONFIG})
     endforeach()
diff --git a/src/acpi.c b/src/acpi.c
index 2850a340d..b33653663 100644
--- a/src/acpi.c
+++ b/src/acpi.c
@@ -2473,10 +2473,9 @@ acpi_init(const device_t *info)
 {
     acpi_t *dev;
 
-    dev = (acpi_t *) malloc(sizeof(acpi_t));
+    dev = (acpi_t *) calloc(1, sizeof(acpi_t));
     if (dev == NULL)
         return NULL;
-    memset(dev, 0x00, sizeof(acpi_t));
 
     cpu_to_acpi = ACPI_TIMER_FREQ / cpuclock;
     dev->vendor = info->local;
diff --git a/src/chipset/stpc.c b/src/chipset/stpc.c
index 23cc56bd3..13dbd97e9 100644
--- a/src/chipset/stpc.c
+++ b/src/chipset/stpc.c
@@ -975,39 +975,24 @@ stpc_serial_init(UNUSED(const device_t *info))
 static void
 stpc_lpt_handlers(stpc_lpt_t *dev, uint8_t val)
 {
-    uint8_t old_addr = (dev->reg1 & 0x03);
-    uint8_t new_addr = (val & 0x03);
+    const uint8_t new_addr = (val & 0x03);
 
-    switch (old_addr) {
-        case 0x1:
-            lpt3_remove();
-            break;
-
-        case 0x2:
-            lpt1_remove();
-            break;
-
-        case 0x3:
-            lpt2_remove();
-            break;
-        default:
-            break;
-    }
+    lpt1_remove();
 
     switch (new_addr) {
         case 0x1:
             stpc_log("STPC: Remapping parallel port to LPT3\n");
-            lpt3_init(0x3bc);
+            lpt1_setup(LPT_MDA_ADDR);
             break;
 
         case 0x2:
             stpc_log("STPC: Remapping parallel port to LPT1\n");
-            lpt1_init(0x378);
+            lpt1_setup(LPT1_ADDR);
             break;
 
         case 0x3:
             stpc_log("STPC: Remapping parallel port to LPT2\n");
-            lpt2_init(0x278);
+            lpt1_setup(LPT2_ADDR);
             break;
 
         default:
@@ -1015,9 +1000,11 @@ stpc_lpt_handlers(stpc_lpt_t *dev, uint8_t val)
             break;
     }
 
-    dev->reg1 = (val & 0x08);
-    dev->reg1 |= new_addr;
-    dev->reg1 |= 0x84; /* reserved bits that default to 1; hardwired? */
+    if (dev != NULL) {
+        dev->reg1 = (val & 0x08);
+        dev->reg1 |= new_addr;
+        dev->reg1 |= 0x84; /* reserved bits that default to 1; hardwired? */
+    }
 }
 
 static void
diff --git a/src/chipset/umc_8886.c b/src/chipset/umc_8886.c
index f96480c2c..0ed062450 100644
--- a/src/chipset/umc_8886.c
+++ b/src/chipset/umc_8886.c
@@ -82,6 +82,8 @@
 #include <86box/hdd.h>
 #include <86box/hdc.h>
 #include <86box/hdc_ide.h>
+#include <86box/keyboard.h>
+#include <86box/machine.h>
 #include <86box/pic.h>
 #include <86box/pci.h>
 #include <86box/port_92.h>
diff --git a/src/chipset/wd76c10.c b/src/chipset/wd76c10.c
index d7d8b0fe2..a375c8eb6 100644
--- a/src/chipset/wd76c10.c
+++ b/src/chipset/wd76c10.c
@@ -542,16 +542,16 @@ wd76c10_ser_par_cs_recalc(wd76c10_t *dev)
     lpt1_remove();
     switch ((dev->ser_par_cs >> 9) & 0x03) {
         case 1:
-            lpt1_init(0x3bc);
-            lpt1_irq(7);
+            lpt1_setup(LPT_MDA_ADDR);
+            lpt1_irq(LPT1_IRQ);
             break;
         case 2:
-            lpt1_init(0x378);
-            lpt1_irq(7);
+            lpt1_setup(LPT1_ADDR);
+            lpt1_irq(LPT1_IRQ);
             break;
         case 3:
-            lpt1_init(0x278);
-            lpt1_irq(7);
+            lpt1_setup(LPT2_ADDR);
+            lpt1_irq(LPT1_IRQ);
             break;
     }
 }
diff --git a/src/device.c b/src/device.c
index 1228eedd2..d7c80be7a 100644
--- a/src/device.c
+++ b/src/device.c
@@ -158,6 +158,13 @@ device_add_common(const device_t *dev, void *p, void *params, int inst)
     void     *priv     = NULL;
     int16_t   c;
 
+    /*
+       IMPORTANT: This is needed to gracefully handle machine
+                  device addition if the relevant device is NULL.
+     */
+    if (dev == NULL)
+        return NULL;
+
     if (!device_available(dev)) {
         wchar_t temp[512] = { 0 };
         swprintf(temp, sizeof_w(temp),
diff --git a/src/device/CMakeLists.txt b/src/device/CMakeLists.txt
index c9da627ef..678c700a5 100644
--- a/src/device/CMakeLists.txt
+++ b/src/device/CMakeLists.txt
@@ -13,48 +13,48 @@
 #
 #          Copyright 2020-2021 David Hrdlička.
 #          Copyright 2021      Andreas J. Reichel.
-#          Copyright 2021-2024 Jasmine Iwanek.
+#          Copyright 2021-2025 Jasmine Iwanek.
 #
 
 add_library(dev OBJECT
     bugger.c
-    cassette.c
     cartridge.c
+    cassette.c
+    clock_ics9xxx.c
     hasp.c
     hwm.c
+    hwm_gl518sm.c
     hwm_lm75.c
     hwm_lm78.c
-    hwm_gl518sm.c
     hwm_vt82c686.c
+    i2c.c
+    i2c_gpio.c
     ibm_5161.c
     isamem.c
     isartc.c
-    ../lpt.c
-    pci_bridge.c
-    postcard.c
-    serial.c
-    unittester.c
-    clock_ics9xxx.c
     isapnp.c
-    i2c.c
-    i2c_gpio.c
-    smbus_piix4.c
-    smbus_ali7101.c
-    smbus_sis5595.c
-    keyboard.c
-    keyboard_xt.c
     kbc_at.c
     kbc_at_dev.c
+    keyboard.c
     keyboard_at.c
+    keyboard_xt.c
+    ../lpt.c
     mouse.c
     mouse_bus.c
-    mouse_serial.c
-    mouse_ps2.c
-    nec_mate_unk.c
-    phoenix_486_jumper.c
-    serial_passthrough.c
-    novell_cardkey.c
     mouse_microtouch_touchscreen.c
+    mouse_ps2.c
+    mouse_serial.c
+    nec_mate_unk.c
+    novell_cardkey.c
+    pci_bridge.c
+    phoenix_486_jumper.c
+    postcard.c
+    serial.c
+    serial_passthrough.c
+    smbus_ali7101.c
+    smbus_piix4.c
+    smbus_sis5595.c
+    unittester.c
 )
 
 if(NOT CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND NOT MSVC)
diff --git a/src/disk/hdc_ide_w83769f.c b/src/disk/hdc_ide_w83769f.c
index 9c0f744b2..7829c5b92 100644
--- a/src/disk/hdc_ide_w83769f.c
+++ b/src/disk/hdc_ide_w83769f.c
@@ -10,7 +10,7 @@
  *
  * Authors: Miran Grca, <mgrca8@gmail.com>
  *
- *          Copyright 2020 Miran Grca.
+ *          Copyright 2020-2025 Miran Grca.
  */
 #include <stdarg.h>
 #include <stdint.h>
diff --git a/src/include/86box/hdc.h b/src/include/86box/hdc.h
index 7731d60d4..e798f2464 100644
--- a/src/include/86box/hdc.h
+++ b/src/include/86box/hdc.h
@@ -13,7 +13,7 @@
  * Authors: Miran Grca, <mgrca8@gmail.com>
  *          Fred N. van Kempen, <decwiz@yahoo.com>
  *
- *          Copyright 2016-2020 Miran Grca.
+ *          Copyright 2016-2025 Miran Grca.
  *          Copyright 2017-2020 Fred N. van Kempen.
  */
 #ifndef EMU_HDC_H
diff --git a/src/include/86box/keyboard.h b/src/include/86box/keyboard.h
index 225ab3936..ec5c05775 100644
--- a/src/include/86box/keyboard.h
+++ b/src/include/86box/keyboard.h
@@ -15,7 +15,7 @@
  *          Fred N. van Kempen, <decwiz@yahoo.com>
  *
  *          Copyright 2008-2019 Sarah Walker.
- *          Copyright 2016-2019 Miran Grca.
+ *          Copyright 2016-2025 Miran Grca.
  *          Copyright 2017-2019 Fred N. van Kempen.
  */
 
@@ -194,8 +194,8 @@ typedef struct scancode {
 extern "C" {
 #endif
 
-extern uint8_t  keyboard_mode;
-extern int      keyboard_scan;
+extern uint8_t keyboard_mode;
+extern int     keyboard_scan;
 
 extern uint16_t scancode_map[768];
 
@@ -232,26 +232,26 @@ extern const device_t keyboard_xt_zenith_device;
 extern const device_t keyboard_xt_hyundai_device;
 extern const device_t keyboard_xtclone_device;
 extern const device_t keyboard_at_device;
-extern const device_t keyboard_at_siemens_device;
 extern const device_t keyboard_at_ami_device;
+extern const device_t keyboard_at_compaq_device;
+extern const device_t keyboard_at_ncr_device;
+extern const device_t keyboard_at_olivetti_device;
+extern const device_t keyboard_at_siemens_device;
 extern const device_t keyboard_at_tg_ami_device;
 extern const device_t keyboard_at_toshiba_device;
-extern const device_t keyboard_at_olivetti_device;
-extern const device_t keyboard_at_ncr_device;
-extern const device_t keyboard_at_compaq_device;
 extern const device_t keyboard_ps2_device;
 extern const device_t keyboard_ps2_ps1_device;
 extern const device_t keyboard_ps2_ps1_pci_device;
 extern const device_t keyboard_ps2_xi8088_device;
 extern const device_t keyboard_ps2_ami_device;
 extern const device_t keyboard_ps2_holtek_device;
-extern const device_t keyboard_ps2_tg_ami_device;
-extern const device_t keyboard_ps2_tg_ami_green_device;
-extern const device_t keyboard_ps2_olivetti_device;
-extern const device_t keyboard_ps2_phoenix_device;
 extern const device_t keyboard_ps2_mca_1_device;
 extern const device_t keyboard_ps2_mca_2_device;
+extern const device_t keyboard_ps2_olivetti_device;
+extern const device_t keyboard_ps2_phoenix_device;
 extern const device_t keyboard_ps2_quadtel_device;
+extern const device_t keyboard_ps2_tg_ami_device;
+extern const device_t keyboard_ps2_tg_ami_green_device;
 extern const device_t keyboard_ps2_pci_device;
 extern const device_t keyboard_ps2_ami_pci_device;
 extern const device_t keyboard_ps2_intel_ami_pci_device;
diff --git a/src/include/86box/lpt.h b/src/include/86box/lpt.h
index 4e95b64c3..674d6340f 100644
--- a/src/include/86box/lpt.h
+++ b/src/include/86box/lpt.h
@@ -31,33 +31,33 @@ typedef struct lpt_device_t {
 } lpt_device_t;
 
 extern void lpt_init(void);
-extern void lpt_port_init(int i, uint16_t port);
+extern void lpt_port_setup(int i, uint16_t port);
 extern void lpt_port_irq(int i, uint8_t irq);
 extern void lpt_port_remove(int i);
 extern void lpt1_remove_ams(void);
 
-#define lpt1_init(a)  lpt_port_init(0, a)
+#define lpt1_setup(a) lpt_port_setup(0, a)
 #define lpt1_irq(a)   lpt_port_irq(0, a)
 #define lpt1_remove() lpt_port_remove(0)
 
-#define lpt2_init(a)  lpt_port_init(1, a)
+#define lpt2_setup(a) lpt_port_setup(1, a)
 #define lpt2_irq(a)   lpt_port_irq(1, a)
 #define lpt2_remove() lpt_port_remove(1)
 
-#define lpt3_init(a)  lpt_port_init(2, a)
+#define lpt3_setup(a) lpt_port_setup(2, a)
 #define lpt3_irq(a)   lpt_port_irq(2, a)
 #define lpt3_remove() lpt_port_remove(2)
 
-#define lpt4_init(a)  lpt_port_init(3, a)
+#define lpt4_setup(a) lpt_port_setup(3, a)
 #define lpt4_irq(a)   lpt_port_irq(3, a)
 #define lpt4_remove() lpt_port_remove(3)
 
 #if 0
-#define lpt5_init(a)  lpt_port_init(4, a)
+#define lpt5_setup(a) lpt_port_setup(4, a)
 #define lpt5_irq(a)   lpt_port_irq(4, a)
 #define lpt5_remove() lpt_port_remove(4)
 
-#define lpt6_init(a)  lpt_port_init(5, a)
+#define lpt6_setup(a) lpt_port_setup(5, a)
 #define lpt6_irq(a)   lpt_port_irq(5, a)
 #define lpt6_remove() lpt_port_remove(5)
 #endif
diff --git a/src/include/86box/sio.h b/src/include/86box/sio.h
index 2dbe97ab0..7fcb376b9 100644
--- a/src/include/86box/sio.h
+++ b/src/include/86box/sio.h
@@ -16,13 +16,20 @@
 #ifndef EMU_SIO_H
 #define EMU_SIO_H
 
-extern void vt82c686_sio_write(uint8_t addr, uint8_t val, void *priv);
-
+/* ACC Micro */
 extern const device_t acc3221_device;
+
+/* Acer / ALi */
 extern const device_t ali5105_device;
+
 extern const device_t ali5123_device;
-extern const device_t f82c710_device;
+
+/* Chips & Technologies */
 extern const device_t f82c606_device;
+
+extern const device_t f82c710_device;
+
+/* SM(S)C */
 extern const device_t fdc37c651_device;
 extern const device_t fdc37c651_ide_device;
 extern const device_t fdc37c661_device;
@@ -35,9 +42,12 @@ extern const device_t fdc37c665_ide_device;
 extern const device_t fdc37c665_ide_pri_device;
 extern const device_t fdc37c665_ide_sec_device;
 extern const device_t fdc37c666_device;
-extern const device_t fdc37c67x_device;
+
 extern const device_t fdc37c669_device;
 extern const device_t fdc37c669_370_device;
+
+extern const device_t fdc37c67x_device;
+
 extern const device_t fdc37c931apm_device;
 extern const device_t fdc37c931apm_compaq_device;
 extern const device_t fdc37c932fr_device;
@@ -46,22 +56,23 @@ extern const device_t fdc37c932_device;
 extern const device_t fdc37c935_device;
 extern const device_t fdc37c935_370_device;
 extern const device_t fdc37c935_no_nvr_device;
+
 extern const device_t fdc37m60x_device;
 extern const device_t fdc37m60x_370_device;
+
+/* ITE */
 extern const device_t it8661f_device;
 extern const device_t it8671f_device;
 extern const device_t i82091aa_device;
 extern const device_t i82091aa_398_device;
 extern const device_t i82091aa_ide_pri_device;
 extern const device_t i82091aa_ide_device;
-extern const device_t pc87306_device;
-extern const device_t pc87307_device;
-extern const device_t pc87307_15c_device;
-extern const device_t pc87307_both_device;
-extern const device_t pc87309_device;
-extern const device_t pc87309_15c_device;
+
+/* National Semiconductors */
 extern const device_t pc87310_device;
 extern const device_t pc87310_ide_device;
+
+extern const device_t pc87306_device;
 extern const device_t pc87311_device;
 extern const device_t pc87311_ide_device;
 extern const device_t pc87332_device;
@@ -69,35 +80,66 @@ extern const device_t pc87332_398_device;
 extern const device_t pc87332_398_ide_device;
 extern const device_t pc87332_398_ide_sec_device;
 extern const device_t pc87332_398_ide_fdcon_device;
+
+extern const device_t pc87307_device;
+extern const device_t pc87307_15c_device;
+extern const device_t pc87307_both_device;
 extern const device_t pc97307_device;
+
+extern const device_t pc87309_device;
+extern const device_t pc87309_15c_device;
+
+/* LG Prime */
 extern const device_t prime3b_device;
 extern const device_t prime3b_ide_device;
 extern const device_t prime3c_device;
 extern const device_t prime3c_ide_device;
+
+/* IBM PS/1 */
 extern const device_t ps1_m2133_sio;
+
+/* Super I/O Detect */
 #ifdef USE_SIO_DETECT
 extern const device_t sio_detect_device;
 #endif /* USE_SIO_DETECT */
+
+/* UMC */
 extern const device_t um8663af_device;
 extern const device_t um8663af_ide_device;
 extern const device_t um8663af_sec_device;
 extern const device_t um8663bf_device;
 extern const device_t um8663bf_ide_device;
 extern const device_t um8663bf_sec_device;
+
 extern const device_t um8669f_device;
 extern const device_t um8669f_ide_device;
 extern const device_t um8669f_ide_sec_device;
+
+/* VIA */
+extern void vt82c686_sio_write(uint8_t addr, uint8_t val, void *priv);
+
 extern const device_t via_vt82c686_sio_device;
+
+/* VLSI */
 extern const device_t vl82c113_device;
+
+/* Winbond */
 extern const device_t w83787f_88h_device;
 extern const device_t w83787f_device;
 extern const device_t w83787f_ide_device;
 extern const device_t w83787f_ide_en_device;
 extern const device_t w83787f_ide_sec_device;
+
 extern const device_t w83877f_device;
 extern const device_t w83877f_president_device;
 extern const device_t w83877tf_device;
 extern const device_t w83877tf_acorp_device;
+
+#define TYPE_W83977EF    0x52F0
+#define TYPE_W83977F     0x9771
+#define TYPE_W83977TF    0x9773
+#define TYPE_W83977ATF   0x9774
+
 extern const device_t w83977f_device;
 extern const device_t w83977f_370_device;
 extern const device_t w83977tf_device;
diff --git a/src/io.c b/src/io.c
index fd87089d0..27f8503b0 100644
--- a/src/io.c
+++ b/src/io.c
@@ -15,7 +15,7 @@
  *          Fred N. van Kempen, <decwiz@yahoo.com>
  *
  *          Copyright 2008-2019 Sarah Walker.
- *          Copyright 2016-2019 Miran Grca.
+ *          Copyright 2016-2025 Miran Grca.
  */
 #include <stdarg.h>
 #include <stdio.h>
@@ -145,6 +145,8 @@ io_sethandler_common(uint16_t base, int size,
         q->next = NULL;
 
         io_last[base + c] = q;
+
+        q = NULL;
     }
 }
 
diff --git a/src/lpt.c b/src/lpt.c
index 3f1c5eb7b..26174d96b 100644
--- a/src/lpt.c
+++ b/src/lpt.c
@@ -219,14 +219,14 @@ lpt_init(void)
         lpt_ports[i].enable_irq = 0x10;
 
         if (lpt_ports[i].enabled) {
-            lpt_port_init(i, default_ports[i]);
+            lpt_port_setup(i, default_ports[i]);
             lpt_port_irq(i, default_irqs[i]);
         }
     }
 }
 
 void
-lpt_port_init(int i, uint16_t port)
+lpt_port_setup(int i, uint16_t port)
 {
     if (lpt_ports[i].enabled) {
         if (lpt_ports[i].addr != 0xffff)
diff --git a/src/machine/m_at_286_386sx.c b/src/machine/m_at_286_386sx.c
index c3dc5c772..cb2a04d07 100644
--- a/src/machine/m_at_286_386sx.c
+++ b/src/machine/m_at_286_386sx.c
@@ -66,7 +66,7 @@ machine_at_mr286_init(const machine_t *model)
 }
 
 static void
-machine_at_headland_common_init(int type)
+machine_at_headland_common_init(const machine_t *model, int type)
 {
     device_add(&keyboard_at_ami_device);
 
@@ -94,7 +94,7 @@ machine_at_tg286m_init(const machine_t *model)
 
     machine_at_common_ide_init(model);
 
-    machine_at_headland_common_init(1);
+    machine_at_headland_common_init(model, 1);
 
     return ret;
 }
@@ -115,7 +115,7 @@ machine_at_ama932j_init(const machine_t *model)
     if (gfxcard[0] == VID_INTERNAL)
         device_add(&oti067_ama932j_device);
 
-    machine_at_headland_common_init(2);
+    machine_at_headland_common_init(model, 2);
 
     device_add(&ali5105_device);
 
@@ -755,7 +755,7 @@ machine_at_acer100t_init(const machine_t *model)
     
     device_add(&ali1409_device);
     if (gfxcard[0] == VID_INTERNAL)
-        device_add(&oti077_acer100t_device);   
+        device_add(&oti077_acer100t_device);
      
     device_add(&ali5105_device);
     
diff --git a/src/machine/m_at_386dx_486.c b/src/machine/m_at_386dx_486.c
index 656db503b..3d152065b 100644
--- a/src/machine/m_at_386dx_486.c
+++ b/src/machine/m_at_386dx_486.c
@@ -50,6 +50,7 @@
 #include <86box/plat_unused.h>
 #include <86box/sound.h>
 
+/* 386DX */
 int
 machine_at_acc386_init(const machine_t *model)
 {
@@ -252,7 +253,7 @@ machine_at_ecs386v_init(const machine_t *model)
     int ret;
 
     ret = bios_load_linear("roms/machines/ecs386v/PANDA_386V.BIN",
-               0x000f0000, 65536, 0);
+                           0x000f0000, 65536, 0);
 
     if (bios_only || !ret)
     return ret;
@@ -1412,7 +1413,7 @@ machine_at_amis76_init(const machine_t *model)
 {
     int ret;
 
-    ret = bios_load_linear_inverted("roms/machines/s76p/S76P.ROM", 
+    ret = bios_load_linear_inverted("roms/machines/s76p/S76P.ROM",
                                     0x000e0000, 131072, 0);
 
     if (bios_only || !ret)
diff --git a/src/machine/m_at_commodore.c b/src/machine/m_at_commodore.c
index 0b45fe60c..b9615c064 100644
--- a/src/machine/m_at_commodore.c
+++ b/src/machine/m_at_commodore.c
@@ -64,13 +64,13 @@ cbm_io_write(UNUSED(uint16_t port), uint8_t val, UNUSED(void *priv))
 
     switch (val & 3) {
         case 1:
-            lpt1_init(LPT_MDA_ADDR);
+            lpt1_setup(LPT_MDA_ADDR);
             break;
         case 2:
-            lpt1_init(LPT1_ADDR);
+            lpt1_setup(LPT1_ADDR);
             break;
         case 3:
-            lpt1_init(LPT2_ADDR);
+            lpt1_setup(LPT2_ADDR);
             break;
 
         default:
diff --git a/src/machine/m_ps1.c b/src/machine/m_ps1.c
index 92846c401..130481394 100644
--- a/src/machine/m_ps1.c
+++ b/src/machine/m_ps1.c
@@ -146,13 +146,13 @@ ps1_write(uint16_t port, uint8_t val, void *priv)
                 if (val & 0x10) {
                     switch ((val >> 5) & 3) {
                         case 0:
-                            lpt1_init(LPT_MDA_ADDR);
+                            lpt1_setup(LPT_MDA_ADDR);
                             break;
                         case 1:
-                            lpt1_init(LPT1_ADDR);
+                            lpt1_setup(LPT1_ADDR);
                             break;
                         case 2:
-                            lpt1_init(LPT2_ADDR);
+                            lpt1_setup(LPT2_ADDR);
                             break;
 
                         default:
@@ -316,7 +316,7 @@ ps1_setup(int model)
     ps->uart = device_add_inst(&ns16450_device, 1);
 
     lpt1_remove();
-    lpt1_init(LPT_MDA_ADDR);
+    lpt1_setup(LPT_MDA_ADDR);
 
     mem_remap_top(384);
 
diff --git a/src/machine/m_ps2_isa.c b/src/machine/m_ps2_isa.c
index 7d024c335..8a2760f15 100644
--- a/src/machine/m_ps2_isa.c
+++ b/src/machine/m_ps2_isa.c
@@ -64,13 +64,13 @@ ps2_write(uint16_t port, uint8_t val, void *priv)
                 if (val & 0x10) {
                     switch ((val >> 5) & 3) {
                         case 0:
-                            lpt1_init(LPT_MDA_ADDR);
+                            lpt1_setup(LPT_MDA_ADDR);
                             break;
                         case 1:
-                            lpt1_init(LPT1_ADDR);
+                            lpt1_setup(LPT1_ADDR);
                             break;
                         case 2:
-                            lpt1_init(LPT2_ADDR);
+                            lpt1_setup(LPT2_ADDR);
                             break;
 
                         default:
@@ -167,7 +167,7 @@ ps2_isa_setup(int model, int cpu_type)
     ps2->uart = device_add_inst(&ns16450_device, 1);
 
     lpt1_remove();
-    lpt1_init(LPT_MDA_ADDR);
+    lpt1_setup(LPT_MDA_ADDR);
 
     device_add(&port_92_device);
 
diff --git a/src/machine/m_ps2_mca.c b/src/machine/m_ps2_mca.c
index 632381ca1..35f3ed125 100644
--- a/src/machine/m_ps2_mca.c
+++ b/src/machine/m_ps2_mca.c
@@ -374,13 +374,13 @@ model_50_write(uint16_t port, uint8_t val)
             if (val & 0x10) {
                 switch ((val >> 5) & 3) {
                     case 0:
-                        lpt1_init(LPT_MDA_ADDR);
+                        lpt1_setup(LPT_MDA_ADDR);
                         break;
                     case 1:
-                        lpt1_init(LPT1_ADDR);
+                        lpt1_setup(LPT1_ADDR);
                         break;
                     case 2:
-                        lpt1_init(LPT2_ADDR);
+                        lpt1_setup(LPT2_ADDR);
                         break;
 
                     default:
@@ -506,13 +506,13 @@ model_55sx_write(uint16_t port, uint8_t val)
             if (val & 0x10) {
                 switch ((val >> 5) & 3) {
                     case 0:
-                        lpt1_init(LPT_MDA_ADDR);
+                        lpt1_setup(LPT_MDA_ADDR);
                         break;
                     case 1:
-                        lpt1_init(LPT1_ADDR);
+                        lpt1_setup(LPT1_ADDR);
                         break;
                     case 2:
-                        lpt1_init(LPT2_ADDR);
+                        lpt1_setup(LPT2_ADDR);
                         break;
 
                     default:
@@ -565,13 +565,13 @@ model_70_type3_write(uint16_t port, uint8_t val)
             if (val & 0x10) {
                 switch ((val >> 5) & 3) {
                     case 0:
-                        lpt1_init(LPT_MDA_ADDR);
+                        lpt1_setup(LPT_MDA_ADDR);
                         break;
                     case 1:
-                        lpt1_init(LPT1_ADDR);
+                        lpt1_setup(LPT1_ADDR);
                         break;
                     case 2:
-                        lpt1_init(LPT2_ADDR);
+                        lpt1_setup(LPT2_ADDR);
                         break;
 
                     default:
@@ -619,13 +619,13 @@ model_80_write(uint16_t port, uint8_t val)
             if (val & 0x10) {
                 switch ((val >> 5) & 3) {
                     case 0:
-                        lpt1_init(LPT_MDA_ADDR);
+                        lpt1_setup(LPT_MDA_ADDR);
                         break;
                     case 1:
-                        lpt1_init(LPT1_ADDR);
+                        lpt1_setup(LPT1_ADDR);
                         break;
                     case 2:
-                        lpt1_init(LPT2_ADDR);
+                        lpt1_setup(LPT2_ADDR);
                         break;
 
                     default:
@@ -846,7 +846,7 @@ ps2_mca_board_common_init(void)
 
     ps2.setup = 0xff;
 
-    lpt1_init(LPT_MDA_ADDR);
+    lpt1_setup(LPT_MDA_ADDR);
 }
 
 static uint8_t
diff --git a/src/machine/m_xt_compaq.c b/src/machine/m_xt_compaq.c
index ed1b3e26c..f8c0b6a19 100644
--- a/src/machine/m_xt_compaq.c
+++ b/src/machine/m_xt_compaq.c
@@ -59,7 +59,7 @@ machine_xt_compaq_deskpro_init(const machine_t *model)
     standalone_gameport_type = &gameport_device;
 
     lpt1_remove();
-    lpt1_init(LPT_MDA_ADDR);
+    lpt1_setup(LPT_MDA_ADDR);
 
     return ret;
 }
@@ -87,7 +87,7 @@ machine_xt_compaq_portable_init(const machine_t *model)
         device_add(&gameport_device);
 
     lpt1_remove();
-    lpt1_init(LPT_MDA_ADDR);
+    lpt1_setup(LPT_MDA_ADDR);
 
     return ret;
 }
diff --git a/src/machine/m_xt_zenith.c b/src/machine/m_xt_zenith.c
index 833529ffb..6c5d556f2 100644
--- a/src/machine/m_xt_zenith.c
+++ b/src/machine/m_xt_zenith.c
@@ -144,7 +144,7 @@ machine_xt_z184_init(const machine_t *model)
 
     lpt1_remove(); /* only one parallel port */
     lpt2_remove();
-    lpt1_init(0x278);
+    lpt1_setup(LPT2_ADDR);
     device_add(&ns8250_device);
     serial_set_next_inst(SERIAL_MAX); /* So that serial_standalone_init() won't do anything. */
 
@@ -198,7 +198,7 @@ machine_xt_z159_init(const machine_t *model)
     /* parallel port is on the memory board */
     lpt1_remove(); /* only one parallel port */
     lpt2_remove();
-    lpt1_init(0x278);
+    lpt1_setup(LPT2_ADDR);
 
     return ret;
 }
diff --git a/src/network/net_plip.c b/src/network/net_plip.c
index f80effeec..8c46213c6 100644
--- a/src/network/net_plip.c
+++ b/src/network/net_plip.c
@@ -26,12 +26,12 @@
 #include <stdarg.h>
 #define HAVE_STDARG_H
 #include <86box/86box.h>
+#include <86box/timer.h>
 #include <86box/lpt.h>
 #include <86box/timer.h>
 #include <86box/pit.h>
 #include <86box/device.h>
 #include <86box/thread.h>
-#include <86box/timer.h>
 #include <86box/network.h>
 #include <86box/plat_unused.h>
 
diff --git a/src/printer/prt_ps.c b/src/printer/prt_ps.c
index 1a9d5c0e8..1298018ee 100644
--- a/src/printer/prt_ps.c
+++ b/src/printer/prt_ps.c
@@ -26,8 +26,8 @@
 #include <string.h>
 #include <wchar.h>
 #include <86box/86box.h>
-#include <86box/lpt.h>
 #include <86box/timer.h>
+#include <86box/lpt.h>
 #include <86box/pit.h>
 #include <86box/path.h>
 #include <86box/plat.h>
diff --git a/src/sio/sio_82091aa.c b/src/sio/sio_82091aa.c
index 76c7ba3f5..d3cd5017a 100644
--- a/src/sio/sio_82091aa.c
+++ b/src/sio/sio_82091aa.c
@@ -78,7 +78,7 @@ lpt1_handler(i82091aa_t *dev)
     }
 
     if ((dev->regs[0x20] & 0x01) && lpt_port)
-        lpt1_init(lpt_port);
+        lpt1_setup(lpt_port);
 
     lpt1_irq((dev->regs[0x20] & 0x08) ? LPT1_IRQ : LPT2_IRQ);
 }
diff --git a/src/sio/sio_acc3221.c b/src/sio/sio_acc3221.c
index d52949d46..203b1c1f1 100644
--- a/src/sio/sio_acc3221.c
+++ b/src/sio/sio_acc3221.c
@@ -305,7 +305,7 @@ acc3221_lpt_handle(acc3221_t *dev)
     lpt1_remove();
 
     if (!(dev->regs[0xbe] & REG_BE_LPT1_DISABLE))
-        lpt1_init(dev->regs[0xbf] << 2);
+        lpt1_setup(dev->regs[0xbf] << 2);
 }
 
 static void
@@ -437,7 +437,7 @@ acc3221_reset(acc3221_t *dev)
     serial_setup(dev->uart[1], COM2_ADDR, COM2_IRQ);
 
     lpt1_remove();
-    lpt1_init(LPT1_ADDR);
+    lpt1_setup(LPT1_ADDR);
     lpt1_irq(LPT1_IRQ);
 
     fdc_reset(dev->fdc);
diff --git a/src/sio/sio_ali5123.c b/src/sio/sio_ali5123.c
index 5380e065a..398d00839 100644
--- a/src/sio/sio_ali5123.c
+++ b/src/sio/sio_ali5123.c
@@ -93,7 +93,7 @@ ali5123_lpt_handler(ali5123_t *dev)
     if (global_enable && local_enable) {
         ld_port = make_port(dev, 3) & 0xFFFC;
         if ((ld_port >= 0x0100) && (ld_port <= 0x0FFC))
-            lpt1_init(ld_port);
+            lpt1_setup(ld_port);
     }
     lpt1_irq(lpt_irq);
 }
@@ -133,8 +133,10 @@ ali5123_serial_handler(ali5123_t *dev, int uart)
 }
 
 static void
-ali5123_reset(ali5123_t *dev)
+ali5123_reset(void *priv)
 {
+    ali5123_t *dev = (ali5123_t *) priv;
+
     memset(dev->regs, 0, 48);
 
     dev->regs[0x20] = 0x43;
@@ -490,7 +492,7 @@ const device_t ali5123_device = {
     .local         = 0x40,
     .init          = ali5123_init,
     .close         = ali5123_close,
-    .reset         = NULL,
+    .reset         = ali5123_reset,
     .available     = NULL,
     .speed_changed = NULL,
     .force_redraw  = NULL,
diff --git a/src/sio/sio_f82c710.c b/src/sio/sio_f82c710.c
index 8882f16e0..a7aa101c6 100644
--- a/src/sio/sio_f82c710.c
+++ b/src/sio/sio_f82c710.c
@@ -104,7 +104,7 @@ f82c710_update_ports(upc_t *dev, int set)
 
     if (dev->regs[0] & 8) {
         lpt_addr = dev->regs[6] * 4;
-        lpt1_init(lpt_addr);
+        lpt1_setup(lpt_addr);
         if ((lpt_addr == LPT1_ADDR) || (lpt_addr == LPT_MDA_ADDR))
             lpt1_irq(LPT1_IRQ);
         else if (lpt_addr == LPT2_ADDR)
@@ -215,7 +215,7 @@ f82c606_update_ports(upc_t *dev, int set)
     }
 
     if (dev->regs[0] & 8) {
-        lpt1_init(((uint16_t) dev->regs[6]) << 2);
+        lpt1_setup(((uint16_t) dev->regs[6]) << 2);
         lpt1_irq(lpt1_int);
         f82c710_log("LPT1 at %04X, IRQ %i\n", ((uint16_t) dev->regs[6]) << 2, lpt1_int);
     }
diff --git a/src/sio/sio_fdc37c669.c b/src/sio/sio_fdc37c669.c
index 7f97e79b0..3be28c6ba 100644
--- a/src/sio/sio_fdc37c669.c
+++ b/src/sio/sio_fdc37c669.c
@@ -107,7 +107,7 @@ fdc37c669_lpt_handler(fdc37c669_t *dev)
 
     lpt_port_remove(dev->id);
     if ((dev->regs[0x01] & 0x04) && (dev->regs[0x23] >= 0x40))
-        lpt_port_init(dev->id, ((uint16_t) (dev->regs[0x23] & mask)) << 2);
+        lpt_port_setup(dev->id, ((uint16_t) (dev->regs[0x23] & mask)) << 2);
 }
 
 static void
diff --git a/src/sio/sio_fdc37c67x.c b/src/sio/sio_fdc37c67x.c
index f0fb8cd64..931734048 100644
--- a/src/sio/sio_fdc37c67x.c
+++ b/src/sio/sio_fdc37c67x.c
@@ -134,7 +134,7 @@ fdc37c67x_lpt_handler(fdc37c67x_t *dev)
     if (global_enable && local_enable) {
         ld_port = make_port(dev, 3) & 0xFFFC;
         if ((ld_port >= 0x0100) && (ld_port <= 0x0FFC))
-            lpt1_init(ld_port);
+            lpt1_setup(ld_port);
     }
     lpt1_irq(lpt_irq);
 }
diff --git a/src/sio/sio_fdc37c6xx.c b/src/sio/sio_fdc37c6xx.c
index 530fff216..0f3460565 100644
--- a/src/sio/sio_fdc37c6xx.c
+++ b/src/sio/sio_fdc37c6xx.c
@@ -111,16 +111,16 @@ lpt1_handler(fdc37c6xx_t *dev)
     lpt1_remove();
     switch (dev->regs[1] & 3) {
         case 1:
-            lpt1_init(LPT_MDA_ADDR);
-            lpt1_irq(7);
+            lpt1_setup(LPT_MDA_ADDR);
+            lpt1_irq(LPT_MDA_IRQ);
             break;
         case 2:
-            lpt1_init(LPT1_ADDR);
-            lpt1_irq(7 /*5*/);
+            lpt1_setup(LPT1_ADDR);
+            lpt1_irq(LPT1_IRQ /*LPT2_IRQ*/);
             break;
         case 3:
-            lpt1_init(LPT2_ADDR);
-            lpt1_irq(7 /*5*/);
+            lpt1_setup(LPT2_ADDR);
+            lpt1_irq(LPT1_IRQ /*LPT2_IRQ*/);
             break;
 
         default:
@@ -252,7 +252,7 @@ fdc37c6xx_reset(fdc37c6xx_t *dev)
     serial_setup(dev->uart[1], COM2_ADDR, COM2_IRQ);
 
     lpt1_remove();
-    lpt1_init(LPT1_ADDR);
+    lpt1_setup(LPT1_ADDR);
 
     fdc_reset(dev->fdc);
     fdc_remove(dev->fdc);
diff --git a/src/sio/sio_fdc37c93x.c b/src/sio/sio_fdc37c93x.c
index 42908ecaf..8d8f76cb6 100644
--- a/src/sio/sio_fdc37c93x.c
+++ b/src/sio/sio_fdc37c93x.c
@@ -35,24 +35,15 @@
 #include <86box/machine.h>
 #include <86box/nvr.h>
 #include <86box/apm.h>
+#include <86box/access_bus.h>
 #include <86box/acpi.h>
 #include <86box/sio.h>
 #include <86box/plat_unused.h>
 
-#define AB_RST 0x80
-
-typedef struct access_bus_t {
-    uint8_t  control;
-    uint8_t  status;
-    uint8_t  own_addr;
-    uint8_t  data;
-    uint8_t  clock;
-    uint16_t base;
-} access_bus_t;
-
 typedef struct fdc37c93x_t {
     uint8_t       chip_id;
     uint8_t       is_apm;
+    uint8_t       is_compaq;
     uint8_t       has_nvr;
     uint8_t       tries;
     uint8_t       port_370;
@@ -61,51 +52,56 @@ typedef struct fdc37c93x_t {
     uint8_t       regs[48];
     uint8_t       ld_regs[11][256];
     uint16_t      superio_base;
+    uint16_t      fdc_base;
+    uint16_t      lpt_base;
+    uint16_t      nvr_pri_base;
+    uint16_t      nvr_sec_base;
+    uint16_t      kbc_base;
     uint16_t      gpio_base; /* Set to EA */
     uint16_t      auxio_base;
-    uint16_t      nvr_sec_base;
+    uint16_t      uart_base[2];
     int           locked;
     int           cur_reg;
     fdc_t        *fdc;
-    serial_t     *uart[2];
     access_bus_t *access_bus;
     nvr_t        *nvr;
     acpi_t       *acpi;
     void         *kbc;
+    serial_t     *uart[2];
 } fdc37c93x_t;
 
 static void    fdc37c93x_write(uint16_t port, uint8_t val, void *priv);
 static uint8_t fdc37c93x_read(uint16_t port, void *priv);
 
 static uint16_t
-make_port_superio(fdc37c93x_t *dev)
+make_port_superio(const fdc37c93x_t *dev)
 {
-    uint16_t r0 = dev->regs[0x26];
-    uint16_t r1 = dev->regs[0x27];
+    const uint16_t r0 = dev->regs[0x26];
+    const uint16_t r1 = dev->regs[0x27];
 
-    uint16_t p = (r1 << 8) + r0;
+    const uint16_t p = (r1 << 8) + r0;
 
     return p;
 }
 
 static uint16_t
-make_port(fdc37c93x_t *dev, uint8_t ld)
+make_port(const fdc37c93x_t *dev, const uint8_t ld)
 {
-    uint16_t r0 = dev->ld_regs[ld][0x60];
-    uint16_t r1 = dev->ld_regs[ld][0x61];
+    const uint16_t r0 = dev->ld_regs[ld][0x60];
+    const uint16_t r1 = dev->ld_regs[ld][0x61];
 
-    uint16_t p = (r0 << 8) + r1;
+    const uint16_t p = (r0 << 8) + r1;
 
     return p;
 }
 
 static uint16_t
-make_port_sec(fdc37c93x_t *dev, uint8_t ld)
+make_port_sec(const fdc37c93x_t *dev, const uint8_t ld)
 {
-    uint16_t r0 = dev->ld_regs[ld][0x62];
-    uint16_t r1 = dev->ld_regs[ld][0x63];
+    const uint16_t r0 = dev->ld_regs[ld][0x62];
+    const uint16_t r1 = dev->ld_regs[ld][0x63];
 
-    uint16_t p = (r0 << 8) + r1;
+    const uint16_t p = (r0 << 8) + r1;
 
     return p;
 }
@@ -150,66 +146,91 @@ fdc37c93x_gpio_write(uint16_t port, uint8_t val, void *priv)
 static void
 fdc37c93x_superio_handler(fdc37c93x_t *dev)
 {
-    io_removehandler(dev->superio_base, 0x0002,
-                     fdc37c93x_read, NULL, NULL, fdc37c93x_write, NULL, NULL, dev);
-    dev->superio_base = make_port_superio(dev);
-    io_sethandler(dev->superio_base, 0x0002,
-                  fdc37c93x_read, NULL, NULL, fdc37c93x_write, NULL, NULL, dev);
+    if (!dev->is_compaq) {
+        if (dev->superio_base != 0x0000)
+            io_removehandler(dev->superio_base, 0x0002,
+                             fdc37c93x_read, NULL, NULL, fdc37c93x_write, NULL, NULL, dev);
+        dev->superio_base = make_port_superio(dev);
+        if (dev->superio_base != 0x0000)
+            io_sethandler(dev->superio_base, 0x0002,
+                          fdc37c93x_read, NULL, NULL, fdc37c93x_write, NULL, NULL, dev);
+    }
 }
 
 static void
 fdc37c93x_fdc_handler(fdc37c93x_t *dev)
 {
-    uint16_t ld_port       = 0;
-    uint8_t  global_enable = !!(dev->regs[0x22] & (1 << 0));
-    uint8_t  local_enable  = !!dev->ld_regs[0][0x30];
+    const uint8_t  global_enable = !!(dev->regs[0x22] & (1 << 0));
+    const uint8_t  local_enable  = !!dev->ld_regs[0][0x30];
+    const uint16_t old_base      = dev->fdc_base;
 
-    fdc_remove(dev->fdc);
-    if (global_enable && local_enable) {
-        ld_port = make_port(dev, 0) & 0xFFF8;
-        if ((ld_port >= 0x0100) && (ld_port <= 0x0FF8))
-            fdc_set_base(dev->fdc, ld_port);
+    dev->fdc_base = 0x0000;
+
+    if (global_enable && local_enable)
+        dev->fdc_base = make_port(dev, 0) & 0xfff8;
+
+    if (dev->fdc_base != old_base) {
+        if ((old_base >= 0x0100) && (old_base <= 0x0ff8))
+            fdc_remove(dev->fdc);
+
+        if ((dev->fdc_base >= 0x0100) && (dev->fdc_base <= 0x0ff8))
+            fdc_set_base(dev->fdc, dev->fdc_base);
     }
 }
 
 static void
 fdc37c93x_lpt_handler(fdc37c93x_t *dev)
 {
-    uint16_t ld_port       = 0;
-    uint8_t  global_enable = !!(dev->regs[0x22] & (1 << 3));
-    uint8_t  local_enable  = !!dev->ld_regs[3][0x30];
-    uint8_t  lpt_irq       = dev->ld_regs[3][0x70];
+    const uint8_t  global_enable = !!(dev->regs[0x22] & (1 << 3));
+    const uint8_t  local_enable  = !!dev->ld_regs[3][0x30];
+    uint8_t        lpt_irq       = dev->ld_regs[3][0x70];
+    const uint16_t old_base      = dev->lpt_base;
 
     if (lpt_irq > 15)
         lpt_irq = 0xff;
 
-    lpt1_remove();
-    if (global_enable && local_enable) {
-        ld_port = make_port(dev, 3) & 0xFFFC;
-        if ((ld_port >= 0x0100) && (ld_port <= 0x0FFC))
-            lpt1_init(ld_port);
+    dev->lpt_base = 0x0000;
+
+    if (global_enable && local_enable)
+        dev->lpt_base = make_port(dev, 3) & 0xfffc;
+
+    if (dev->lpt_base != old_base) {
+        if ((old_base >= 0x0100) && (old_base <= 0x0ffc))
+            lpt1_remove();
+
+        if ((dev->lpt_base >= 0x0100) && (dev->lpt_base <= 0x0ffc))
+            lpt1_setup(dev->lpt_base);
     }
+
     lpt1_irq(lpt_irq);
 }
 
 static void
-fdc37c93x_serial_handler(fdc37c93x_t *dev, int uart)
+fdc37c93x_serial_handler(fdc37c93x_t *dev, const int uart)
 {
-    uint16_t ld_port       = 0;
-    uint8_t  uart_no       = 4 + uart;
-    uint8_t  global_enable = !!(dev->regs[0x22] & (1 << uart_no));
-    uint8_t  local_enable  = !!dev->ld_regs[uart_no][0x30];
+    const uint8_t  uart_no       = 4 + uart;
+    const uint8_t  global_enable = !!(dev->regs[0x22] & (1 << uart_no));
+    const uint8_t  local_enable  = !!dev->ld_regs[uart_no][0x30];
+    const uint16_t old_base      = dev->uart_base[uart];
 
-    serial_remove(dev->uart[uart]);
-    if (global_enable && local_enable) {
-        ld_port = make_port(dev, uart_no) & 0xFFF8;
-        if ((ld_port >= 0x0100) && (ld_port <= 0x0FF8))
-            serial_setup(dev->uart[uart], ld_port, dev->ld_regs[uart_no][0x70]);
+    dev->uart_base[uart] = 0x0000;
+
+    if (global_enable && local_enable)
+        dev->uart_base[uart] = make_port(dev, uart_no) & 0xfff8;
+
+    if (dev->uart_base[uart] != old_base) {
+        if ((old_base >= 0x0100) && (old_base <= 0x0ff8))
+            serial_remove(dev->uart[uart]);
+
+        if ((dev->uart_base[uart] >= 0x0100) && (dev->uart_base[uart] <= 0x0ff8))
+            serial_setup(dev->uart[uart], dev->uart_base[uart], dev->ld_regs[uart_no][0x70]);
     }
+
+    serial_irq(dev->uart[uart], dev->ld_regs[uart_no][0x70]);
 }
 
 static void
-fdc37c93x_nvr_pri_handler(fdc37c93x_t *dev)
+fdc37c93x_nvr_pri_handler(const fdc37c93x_t *dev)
 {
     uint8_t  local_enable = !!dev->ld_regs[6][0x30];
 
@@ -224,18 +245,24 @@ fdc37c93x_nvr_pri_handler(fdc37c93x_t *dev)
 static void
 fdc37c93x_nvr_sec_handler(fdc37c93x_t *dev)
 {
-    uint16_t ld_port      = 0;
-    uint8_t  local_enable = !!dev->ld_regs[6][0x30];
+    uint8_t        local_enable = !!dev->ld_regs[6][0x30];
+    const uint16_t old_base     = dev->nvr_sec_base;
 
     local_enable &= (((dev->ld_regs[6][0xf0] & 0xe0) == 0x80) ||
                      ((dev->ld_regs[6][0xf0] & 0xe0) == 0xe0));
 
-    nvr_at_sec_handler(0, dev->nvr_sec_base, dev->nvr);
-    if (local_enable) {
-        dev->nvr_sec_base = ld_port = make_port_sec(dev, 6) & 0xFFFE;
+    dev->nvr_sec_base = 0x0000;
+
+    if (local_enable)
+        dev->nvr_sec_base = make_port_sec(dev, 6) & 0xfffe;
+
+    if (dev->nvr_sec_base != old_base) {
+        if ((old_base > 0x0000) && (old_base <= 0x0ffe))
+            nvr_at_sec_handler(0, dev->nvr_sec_base, dev->nvr);
+
         /* Datasheet erratum: First it says minimum address is 0x0100, but later implies that it's 0x0000
                               and that default is 0x0070, same as (unrelocatable) primary NVR. */
-        if (ld_port <= 0x0FFE)
+        if ((dev->nvr_sec_base > 0x0000) && (dev->nvr_sec_base <= 0x0ffe))
             nvr_at_sec_handler(1, dev->nvr_sec_base, dev->nvr);
     }
 }
@@ -243,22 +270,32 @@ fdc37c93x_nvr_sec_handler(fdc37c93x_t *dev)
 static void
 fdc37c93x_kbc_handler(fdc37c93x_t *dev)
 {
-    uint8_t  local_enable = !!dev->ld_regs[7][0x30];
+    const uint8_t  local_enable = !!dev->ld_regs[7][0x30];
+    const uint16_t old_base = dev->kbc_base;
 
-    kbc_at_handler(local_enable, dev->kbc);
+    dev->kbc_base = local_enable ? 0x0060 : 0x0000;
+
+    if (dev->kbc_base != old_base)
+        kbc_at_handler(local_enable, dev->kbc);
 }
 
 static void
 fdc37c93x_auxio_handler(fdc37c93x_t *dev)
 {
-    uint16_t ld_port      = 0;
-    uint8_t  local_enable = !!dev->ld_regs[8][0x30];
+    const uint8_t local_enable = !!dev->ld_regs[8][0x30];
+    const uint16_t old_base    = dev->auxio_base;
 
-    io_removehandler(dev->auxio_base, 0x0001,
-                     fdc37c93x_auxio_read, NULL, NULL, fdc37c93x_auxio_write, NULL, NULL, dev);
-    if (local_enable) {
-        dev->auxio_base = ld_port = make_port(dev, 8);
-        if ((ld_port >= 0x0100) && (ld_port <= 0x0FFF))
+    if (local_enable)
+        dev->auxio_base = make_port(dev, 8);
+    else
+        dev->auxio_base = 0x0000;
+
+    if (dev->auxio_base != old_base) {
+        if ((old_base >= 0x0100) && (old_base <= 0x0fff))
+            io_removehandler(old_base, 0x0001,
+                         fdc37c93x_auxio_read, NULL, NULL, fdc37c93x_auxio_write, NULL, NULL, dev);
+
+        if ((dev->auxio_base >= 0x0100) && (dev->auxio_base <= 0x0fff))
             io_sethandler(dev->auxio_base, 0x0001,
                           fdc37c93x_auxio_read, NULL, NULL, fdc37c93x_auxio_write, NULL, NULL, dev);
     }
@@ -267,113 +304,55 @@ fdc37c93x_auxio_handler(fdc37c93x_t *dev)
 static void
 fdc37c93x_gpio_handler(fdc37c93x_t *dev)
 {
-    uint16_t ld_port = 0;
-    uint8_t  local_enable;
+    const uint8_t local_enable = !dev->locked && !!(dev->regs[0x03] & 0x80);
+    const uint16_t old_base    = dev->gpio_base;
 
-    local_enable = !!(dev->regs[0x03] & 0x80);
+    dev->gpio_base = 0x0000;
 
-    io_removehandler(dev->gpio_base, 0x0002,
-                     fdc37c93x_gpio_read, NULL, NULL, fdc37c93x_gpio_write, NULL, NULL, dev);
-    if (local_enable) {
-        switch (dev->regs[0x03] & 0x03) {
-            case 0:
-                ld_port = 0xe0;
-                break;
-            case 1:
-                ld_port = 0xe2;
-                break;
-            case 2:
-                ld_port = 0xe4;
-                break;
-            case 3:
-                ld_port = 0xea; /* Default */
-                break;
+    if (local_enable)  switch (dev->regs[0x03] & 0x03) {
+        default:
+            break;
+        case 0:
+            dev->gpio_base = 0x00e0;
+            break;
+        case 1:
+            dev->gpio_base = 0x00e2;
+            break;
+        case 2:
+            dev->gpio_base = 0x00e4;
+            break;
+        case 3:
+            dev->gpio_base = 0x00ea; /* Default */
+            break;
+    }
 
-            default:
-                break;
-        }
-        dev->gpio_base = ld_port;
-        if (ld_port > 0x0000)
+    if (dev->gpio_base != old_base) {
+        if (old_base != 0x0000)
+            io_removehandler(old_base, 0x0002,
+                         fdc37c93x_gpio_read, NULL, NULL, fdc37c93x_gpio_write, NULL, NULL, dev);
+
+        if (dev->gpio_base > 0x0000)
             io_sethandler(dev->gpio_base, 0x0002,
                           fdc37c93x_gpio_read, NULL, NULL, fdc37c93x_gpio_write, NULL, NULL, dev);
     }
 }
 
-static uint8_t
-fdc37c93x_access_bus_read(uint16_t port, void *priv)
-{
-    const access_bus_t *dev = (access_bus_t *) priv;
-    uint8_t             ret = 0xff;
-
-    switch (port & 3) {
-        case 0:
-            ret = (dev->status & 0xBF);
-            break;
-        case 1:
-            ret = (dev->own_addr & 0x7F);
-            break;
-        case 2:
-            ret = dev->data;
-            break;
-        case 3:
-            ret = (dev->clock & 0x87);
-            break;
-
-        default:
-            break;
-    }
-
-    return ret;
-}
-
-static void
-fdc37c93x_access_bus_write(uint16_t port, uint8_t val, void *priv)
-{
-    access_bus_t *dev = (access_bus_t *) priv;
-
-    switch (port & 3) {
-        case 0:
-            dev->control = (val & 0xCF);
-            break;
-        case 1:
-            dev->own_addr = (val & 0x7F);
-            break;
-        case 2:
-            dev->data = val;
-            break;
-        case 3:
-            dev->clock &= 0x80;
-            dev->clock |= (val & 0x07);
-            break;
-
-        default:
-            break;
-    }
-}
-
 static void
 fdc37c93x_access_bus_handler(fdc37c93x_t *dev)
 {
-    uint16_t ld_port       = 0;
-    uint8_t  global_enable = !!(dev->regs[0x22] & (1 << 6));
-    uint8_t  local_enable  = !!dev->ld_regs[9][0x30];
+    const uint8_t  global_enable = !!(dev->regs[0x22] & (1 << 6));
+    const uint8_t  local_enable  = !!dev->ld_regs[9][0x30];
+    const uint16_t ld_port = dev->access_bus->base = make_port(dev, 9);
 
-    io_removehandler(dev->access_bus->base, 0x0004,
-                     fdc37c93x_access_bus_read, NULL, NULL, fdc37c93x_access_bus_write, NULL, NULL, dev->access_bus);
-    if (global_enable && local_enable) {
-        dev->access_bus->base = ld_port = make_port(dev, 9);
-        if ((ld_port >= 0x0100) && (ld_port <= 0x0FFC))
-            io_sethandler(dev->access_bus->base, 0x0004,
-                          fdc37c93x_access_bus_read, NULL, NULL, fdc37c93x_access_bus_write, NULL, NULL, dev->access_bus);
-    }
+    access_bus_handler(dev->access_bus, global_enable && local_enable, ld_port);
 }
 
 static void
 fdc37c93x_acpi_handler(fdc37c93x_t *dev)
 {
-    uint16_t ld_port      = 0;
-    uint8_t  local_enable = !!dev->ld_regs[0x0a][0x30];
-    uint8_t  sci_irq      = dev->ld_regs[0x0a][0x70];
+    uint16_t      ld_port;
+    const uint8_t local_enable = !!dev->ld_regs[0x0a][0x30];
+    const uint8_t sci_irq      = dev->ld_regs[0x0a][0x70];
 
     acpi_update_io_mapping(dev->acpi, 0x0000, local_enable);
     if (local_enable) {
@@ -392,41 +371,49 @@ fdc37c93x_acpi_handler(fdc37c93x_t *dev)
     acpi_set_irq_line(dev->acpi, sci_irq);
 }
 
+static void
+fdc37c93x_state_change(fdc37c93x_t *dev, const uint8_t locked)
+{
+    dev->locked = locked;
+    fdc_3f1_enable(dev->fdc, !locked);
+    fdc37c93x_gpio_handler(dev);
+}
+
 static void
 fdc37c93x_write(uint16_t port, uint8_t val, void *priv)
 {
     fdc37c93x_t *dev    = (fdc37c93x_t *) priv;
     uint8_t      index  = (port & 1) ? 0 : 1;
-    uint8_t      valxor = 0x00;
-    uint8_t      keep = 0x00;
+    uint8_t      valxor;
 
     /* Compaq Presario 4500: Unlock at FB, Register at EA, Data at EB, Lock at F9. */
-    if ((port == 0xea) || (port == 0xf9) || (port == 0xfb))
+    if (port == 0xea)
         index = 1;
     else if (port == 0xeb)
         index = 0;
 
-    if (index) {
-        if ((val == 0x55) && !dev->locked) {
+    if (port == 0xfb) {
+        fdc37c93x_state_change(dev, 1);
+        dev->tries = 0;
+        return;
+    } else if (port == 0xf9) {
+        fdc37c93x_state_change(dev, 0);
+        return;
+    } else if (index) {
+        if ((!dev->is_compaq) && (val == 0x55) && !dev->locked) {
             if (dev->tries) {
-                dev->locked = 1;
-                fdc_3f1_enable(dev->fdc, 0);
+                fdc37c93x_state_change(dev, 1);
                 dev->tries = 0;
             } else
                 dev->tries++;
-        } else {
-            if (dev->locked) {
-                if (val == 0xaa) {
-                    dev->locked = 0;
-                    fdc_3f1_enable(dev->fdc, 1);
-                    return;
-                }
-                dev->cur_reg = val;
-            } else {
-                if (dev->tries)
-                    dev->tries = 0;
+        } else if (dev->locked) {
+            if ((!dev->is_compaq) && (val == 0xaa)) {
+                fdc37c93x_state_change(dev, 0);
+                return;
             }
-        }
+            dev->cur_reg = val;
+        } else if ((!dev->is_compaq) && dev->tries)
+            dev->tries = 0;
         return;
     } else {
         if (dev->locked) {
@@ -436,6 +423,8 @@ fdc37c93x_write(uint16_t port, uint8_t val, void *priv)
                     return;
                 dev->regs[dev->cur_reg] = val;
             } else {
+                uint8_t keep = 0x00;
+
                 valxor = val ^ dev->ld_regs[dev->regs[7]][dev->cur_reg];
                 if (((dev->cur_reg & 0xF0) == 0x70) && (dev->regs[7] < 4))
                     return;
@@ -479,9 +468,11 @@ fdc37c93x_write(uint16_t port, uint8_t val, void *priv)
 
     if (dev->cur_reg < 48) {
         switch (dev->cur_reg) {
+            case 0x02:
+                if (val == 0x02)
+                    fdc37c93x_state_change(dev, 0);
+                break;
             case 0x03:
-                if (valxor & 0x83)
-                    fdc37c93x_gpio_handler(dev);
                 dev->regs[0x03] &= 0x83;
                 break;
             case 0x22:
@@ -788,91 +779,95 @@ fdc37c93x_read(uint16_t port, void *priv)
 static void
 fdc37c93x_reset(fdc37c93x_t *dev)
 {
-    memset(dev->regs, 0, 48);
+    memset(dev->regs, 0x00, sizeof(dev->regs));
 
     dev->regs[0x03] = 0x03;
     dev->regs[0x20] = dev->chip_id;
     dev->regs[0x21] = 0x01;
     dev->regs[0x22] = 0x39;
     dev->regs[0x24] = 0x04;
-    if (dev->chip_id != 0x02) {
-        dev->regs[0x26] = dev->port_370 ? 0x70 : 0xF0;
-        dev->regs[0x27] = 0x03;
-    }
+    dev->regs[0x26] = dev->port_370 ? 0x70 : 0xf0;
+    dev->regs[0x27] = 0x03;
 
-    for (uint8_t i = 0; i < 11; i++)
-        memset(dev->ld_regs[i], 0, 256);
+    memset(dev->ld_regs, 0x00, sizeof(dev->ld_regs));
 
     /* Logical device 0: FDD */
-    dev->ld_regs[0][0x30] = 0;
-    dev->ld_regs[0][0x60] = 3;
-    dev->ld_regs[0][0x61] = 0xF0;
-    dev->ld_regs[0][0x70] = 6;
-    dev->ld_regs[0][0x74] = 2;
-    dev->ld_regs[0][0xF0] = 0xE;
-    dev->ld_regs[0][0xF2] = 0xFF;
+    dev->ld_regs[0x00][0x30] = 0x00;
+    dev->ld_regs[0x00][0x60] = 0x03;
+    dev->ld_regs[0x00][0x61] = 0xf0;
+    dev->ld_regs[0x00][0x70] = 0x06;
+    dev->ld_regs[0x00][0x74] = 0x02;
+    dev->ld_regs[0x00][0xf0] = 0x0e;
+    dev->ld_regs[0x00][0xf2] = 0xff;
 
     /* Logical device 1: IDE1 */
-    dev->ld_regs[1][0x30] = 0;
-    dev->ld_regs[1][0x60] = 1;
-    dev->ld_regs[1][0x61] = 0xF0;
-    dev->ld_regs[1][0x62] = 3;
-    dev->ld_regs[1][0x63] = 0xF6;
-    dev->ld_regs[1][0x70] = 0xE;
-    dev->ld_regs[1][0xF0] = 0xC;
+    dev->ld_regs[0x01][0x30] = 0x00;
+    dev->ld_regs[0x01][0x60] = 0x01;
+    dev->ld_regs[0x01][0x61] = 0xf0;
+    dev->ld_regs[0x01][0x62] = 0x03;
+    dev->ld_regs[0x01][0x63] = 0xf6;
+    dev->ld_regs[0x01][0x70] = 0x0e;
+    dev->ld_regs[0x01][0xf0] = 0x0c;
 
     /* Logical device 2: IDE2 */
-    dev->ld_regs[2][0x30] = 0;
-    dev->ld_regs[2][0x60] = 1;
-    dev->ld_regs[2][0x61] = 0x70;
-    dev->ld_regs[2][0x62] = 3;
-    dev->ld_regs[2][0x63] = 0x76;
-    dev->ld_regs[2][0x70] = 0xF;
+    dev->ld_regs[0x02][0x30] = 0x00;
+    dev->ld_regs[0x02][0x60] = 0x01;
+    dev->ld_regs[0x02][0x61] = 0x70;
+    dev->ld_regs[0x02][0x62] = 0x03;
+    dev->ld_regs[0x02][0x63] = 0x76;
+    dev->ld_regs[0x02][0x70] = 0x0f;
 
     /* Logical device 3: Parallel Port */
-    dev->ld_regs[3][0x30] = 0;
-    dev->ld_regs[3][0x60] = 3;
-    dev->ld_regs[3][0x61] = 0x78;
-    dev->ld_regs[3][0x70] = 7;
-    dev->ld_regs[3][0x74] = 4;
-    dev->ld_regs[3][0xF0] = 0x3C;
+    dev->ld_regs[0x03][0x30] = 0x00;
+    dev->ld_regs[0x03][0x60] = 0x03;
+    dev->ld_regs[0x03][0x61] = 0x78;
+    dev->ld_regs[0x03][0x70] = 0x07;
+    dev->ld_regs[0x03][0x74] = 0x04;
+    dev->ld_regs[0x03][0xf0] = 0x3c;
 
     /* Logical device 4: Serial Port 1 */
-    dev->ld_regs[4][0x30] = 0;
-    dev->ld_regs[4][0x60] = 3;
-    dev->ld_regs[4][0x61] = 0xf8;
-    dev->ld_regs[4][0x70] = 4;
-    dev->ld_regs[4][0xF0] = 3;
-    serial_setup(dev->uart[0], COM1_ADDR, dev->ld_regs[4][0x70]);
+    dev->ld_regs[0x04][0x30] = 0x00;
+    dev->ld_regs[0x04][0x60] = 0x03;
+    dev->ld_regs[0x04][0x61] = 0xf8;
+    dev->ld_regs[0x04][0x70] = 0x04;
+    dev->ld_regs[0x04][0xf0] = 0x03;
+    serial_irq(dev->uart[0], dev->ld_regs[4][0x70]);
 
     /* Logical device 5: Serial Port 2 */
-    dev->ld_regs[5][0x30] = 0;
-    dev->ld_regs[5][0x60] = 2;
-    dev->ld_regs[5][0x61] = 0xf8;
-    dev->ld_regs[5][0x70] = 3;
-    dev->ld_regs[5][0x74] = 4;
-    dev->ld_regs[5][0xF1] = 2;
-    dev->ld_regs[5][0xF2] = 3;
-    serial_setup(dev->uart[1], COM2_ADDR, dev->ld_regs[5][0x70]);
+    dev->ld_regs[0x05][0x30] = 0x00;
+    dev->ld_regs[0x05][0x60] = 0x02;
+    dev->ld_regs[0x05][0x61] = 0xf8;
+    dev->ld_regs[0x05][0x70] = 0x03;
+    dev->ld_regs[0x05][0x74] = 0x04;
+    dev->ld_regs[0x05][0xf1] = 0x02;
+    dev->ld_regs[0x05][0xf2] = 0x03;
+    serial_irq(dev->uart[1], dev->ld_regs[5][0x70]);
 
     /* Logical device 6: RTC */
-    dev->ld_regs[6][0x30] = 0;
-    dev->ld_regs[6][0x60] = 0x70;
-    if (dev->chip_id != 0x02)
-        dev->ld_regs[6][0x63] = (dev->has_nvr) ? 0x70 : 0x00;
-    dev->ld_regs[6][0xF0] = 0;
-    dev->ld_regs[6][0xF4] = 3;
+    dev->ld_regs[0x06][0x30] = 0x00;
+    dev->ld_regs[0x06][0x63] = (dev->has_nvr) ? 0x70 : 0x00;
+    dev->ld_regs[0x06][0xf0] = 0x00;
+    dev->ld_regs[0x06][0xf4] = 0x03;
 
     /* Logical device 7: Keyboard */
-    dev->ld_regs[7][0x30] = 0;
-    dev->ld_regs[7][0x61] = 0x60;
-    dev->ld_regs[7][0x70] = 1;
+    dev->ld_regs[0x07][0x30] = 0x00;
+    dev->ld_regs[0x07][0x61] = 0x60;
+    dev->ld_regs[0x07][0x70] = 0x01;
 
     /* Logical device 8: Auxiliary I/O */
+    dev->ld_regs[0x08][0x30] = 0x00;
+    dev->ld_regs[0x08][0x60] = 0x00;
+    dev->ld_regs[0x08][0x61] = 0x00;
 
     /* Logical device 9: ACCESS.bus */
+    dev->ld_regs[0x09][0x30] = 0x00;
+    dev->ld_regs[0x09][0x60] = 0x00;
+    dev->ld_regs[0x09][0x61] = 0x00;
 
     /* Logical device A: ACPI */
+    dev->ld_regs[0x0a][0x30] = 0x00;
+    dev->ld_regs[0x0a][0x60] = 0x00;
+    dev->ld_regs[0x0a][0x61] = 0x00;
 
     fdc37c93x_gpio_handler(dev);
     fdc37c93x_lpt_handler(dev);
@@ -907,36 +902,6 @@ fdc37c93x_reset(fdc37c93x_t *dev)
     dev->locked = 0;
 }
 
-static void
-access_bus_close(void *priv)
-{
-    access_bus_t *dev = (access_bus_t *) priv;
-
-    free(dev);
-}
-
-static void *
-access_bus_init(UNUSED(const device_t *info))
-{
-    access_bus_t *dev = (access_bus_t *) calloc(1, sizeof(access_bus_t));
-
-    return dev;
-}
-
-static const device_t access_bus_device = {
-    .name          = "SMC FDC37C932FR ACCESS.bus",
-    .internal_name = "access_bus",
-    .flags         = 0,
-    .local         = 0x03,
-    .init          = access_bus_init,
-    .close         = access_bus_close,
-    .reset         = NULL,
-    .available     = NULL,
-    .speed_changed = NULL,
-    .force_redraw  = NULL,
-    .config        = NULL
-};
-
 static void
 fdc37c93x_close(void *priv)
 {
@@ -948,19 +913,18 @@ fdc37c93x_close(void *priv)
 static void *
 fdc37c93x_init(const device_t *info)
 {
-    int          is_compaq;
     fdc37c93x_t *dev = (fdc37c93x_t *) calloc(1, sizeof(fdc37c93x_t));
 
     dev->fdc = device_add(&fdc_at_smc_device);
 
-    dev->uart[0]  = device_add_inst(&ns16550_device, 1);
-    dev->uart[1]  = device_add_inst(&ns16550_device, 2);
+    dev->uart[0]   = device_add_inst(&ns16550_device, 1);
+    dev->uart[1]   = device_add_inst(&ns16550_device, 2);
 
-    dev->chip_id  = info->local & 0xff;
-    dev->is_apm   = (info->local >> 8) & 0x01;
-    is_compaq     = (info->local >> 8) & 0x02;
-    dev->has_nvr  = !((info->local >> 8) & 0x04);
-    dev->port_370 = ((info->local >> 8) & 0x08);
+    dev->chip_id   = info->local & 0xff;
+    dev->is_apm    = (info->local >> 8) & 0x01;
+    dev->is_compaq = (info->local >> 8) & 0x02;
+    dev->has_nvr   = !((info->local >> 8) & 0x04);
+    dev->port_370  = ((info->local >> 8) & 0x08);
 
     dev->gpio_regs[0] = 0xff;
 #if 0
@@ -981,7 +945,7 @@ fdc37c93x_init(const device_t *info)
     if (dev->is_apm)
         dev->acpi = device_add(&acpi_smc_device);
 
-    if (is_compaq) {
+    if (dev->is_compaq) {
         io_sethandler(0x0ea, 0x0002,
                       fdc37c93x_read, NULL, NULL, fdc37c93x_write, NULL, NULL, dev);
         io_sethandler(0x0f9, 0x0001,
@@ -992,6 +956,16 @@ fdc37c93x_init(const device_t *info)
 
     dev->kbc = device_add(&keyboard_ps2_ami_pci_device);
 
+    /* Set the defaults here so the ports can be removed by fdc37c93x_reset(). */
+    dev->fdc_base     = 0x03f0;
+    dev->lpt_base     = 0x0378;
+    dev->uart_base[0] = 0x03f8;
+    dev->uart_base[1] = 0x02f8;
+    dev->nvr_pri_base = 0x0070;
+    dev->nvr_sec_base = 0x0070;
+    dev->kbc_base     = 0x0060;
+    dev->gpio_base    = 0x00ea;
+
     fdc37c93x_reset(dev);
 
     if (dev->chip_id == 0x02) {
@@ -1115,4 +1089,3 @@ const device_t fdc37c935_no_nvr_device = {
     .force_redraw  = NULL,
     .config        = NULL
 };
-
diff --git a/src/sio/sio_fdc37m60x.c b/src/sio/sio_fdc37m60x.c
index 671b3581b..11d2f3349 100644
--- a/src/sio/sio_fdc37m60x.c
+++ b/src/sio/sio_fdc37m60x.c
@@ -216,7 +216,7 @@ fdc37m60x_lpt_handler(fdc37m60x_t *dev)
     lpt1_remove();
 
     if (ENABLED(3) || (POWER_CONTROL & 0x08)) {
-        lpt1_init(BASE_ADDRESS(3));
+        lpt1_setup(BASE_ADDRESS(3));
         lpt1_irq(IRQ(3) & 0xf);
         fdc37m60x_log("SMC60x-LPT: BASE %04x IRQ %d\n", BASE_ADDRESS(3), IRQ(3) & 0xf);
     }
diff --git a/src/sio/sio_it86x1f.c b/src/sio/sio_it86x1f.c
index 1cde8657e..b3553bf54 100644
--- a/src/sio/sio_it86x1f.c
+++ b/src/sio/sio_it86x1f.c
@@ -294,7 +294,7 @@ it8661f_pnp_config_changed(uint8_t ld, isapnp_device_config_t *config, void *pri
 
             if (config->activate && (config->io[0].base != ISAPNP_IO_DISABLED)) {
                 it86x1f_log("IT86x1F: LPT enabled at port %04X IRQ %d\n", config->io[0].base, config->irq[0].irq);
-                lpt1_init(config->io[0].base);
+                lpt1_setup(config->io[0].base);
             } else {
                 it86x1f_log("IT86x1F: LPT disabled\n");
             }
diff --git a/src/sio/sio_pc87306.c b/src/sio/sio_pc87306.c
index 33cb0d865..41d69b0cc 100644
--- a/src/sio/sio_pc87306.c
+++ b/src/sio/sio_pc87306.c
@@ -154,7 +154,7 @@ lpt1_handler(pc87306_t *dev)
         lpt_irq = (dev->regs[0x1b] & 0x20) ? 7 : 5;
 
     if (lpt_port)
-        lpt1_init(lpt_port);
+        lpt1_setup(lpt_port);
 
     lpt1_irq(lpt_irq);
 }
@@ -303,26 +303,26 @@ pc87306_write(uint16_t port, uint8_t val, void *priv)
             }
             break;
         case 0x02:
-            if (valxor & 1) {
+            if (valxor & 0x01) {
                 lpt1_remove();
-                serial_remove(dev->uart[0]);
-                serial_remove(dev->uart[1]);
+                serial_remove(dev->uart[0x00]);
+                serial_remove(dev->uart[0x01]);
                 fdc_remove(dev->fdc);
 
                 if (!(val & 1)) {
-                    if (dev->regs[0] & 1)
+                    if (dev->regs[0x00] & 0x01)
                         lpt1_handler(dev);
-                    if (dev->regs[0] & 2)
+                    if (dev->regs[0x00] & 0x02)
                         serial_handler(dev, 0);
-                    if (dev->regs[0] & 4)
+                    if (dev->regs[0x00] & 0x04)
                         serial_handler(dev, 1);
-                    if (dev->regs[0] & 8)
-                        fdc_set_base(dev->fdc, (dev->regs[0] & 0x20) ? FDC_SECONDARY_ADDR : FDC_PRIMARY_ADDR);
+                    if (dev->regs[0x00] & 0x08)
+                        fdc_set_base(dev->fdc, (dev->regs[0x00] & 0x20) ? FDC_SECONDARY_ADDR : FDC_PRIMARY_ADDR);
                 }
             }
-            if (valxor & 8) {
+            if (valxor & 0x08) {
                 lpt1_remove();
-                if ((dev->regs[0] & 1) && !(dev->regs[2] & 1))
+                if ((dev->regs[0x00] & 1) && !(dev->regs[0x02] & 1))
                     lpt1_handler(dev);
             }
             break;
@@ -359,7 +359,7 @@ pc87306_write(uint16_t port, uint8_t val, void *priv)
                     lpt1_handler(dev);
             }
             break;
-        case 0x1B:
+        case 0x1b:
             if (valxor & 0x70) {
                 lpt1_remove();
                 if (!(val & 0x40))
@@ -368,7 +368,7 @@ pc87306_write(uint16_t port, uint8_t val, void *priv)
                     lpt1_handler(dev);
             }
             break;
-        case 0x1C:
+        case 0x1c:
             if (valxor) {
                 serial_remove(dev->uart[0]);
                 serial_remove(dev->uart[1]);
diff --git a/src/sio/sio_pc87307.c b/src/sio/sio_pc87307.c
index eba0748c9..ae21d34af 100644
--- a/src/sio/sio_pc87307.c
+++ b/src/sio/sio_pc87307.c
@@ -200,7 +200,7 @@ lpt1_handler(pc87307_t *dev)
     irq    = (dev->ld_regs[0x04][0x40] & 0x0f);
 
     if (active && (addr <= 0xfffc)) {
-        lpt1_init(addr);
+        lpt1_setup(addr);
         lpt1_irq(irq);
     }
 }
diff --git a/src/sio/sio_pc87309.c b/src/sio/sio_pc87309.c
index 1b790bc6b..da53802c1 100644
--- a/src/sio/sio_pc87309.c
+++ b/src/sio/sio_pc87309.c
@@ -137,7 +137,7 @@ lpt1_handler(pc87309_t *dev)
     irq    = (dev->ld_regs[0x01][0x40] & 0x0f);
 
     if (active) {
-        lpt1_init(addr);
+        lpt1_setup(addr);
         lpt1_irq(irq);
     }
 }
diff --git a/src/sio/sio_pc87310.c b/src/sio/sio_pc87310.c
index 674db6364..5bd595f05 100644
--- a/src/sio/sio_pc87310.c
+++ b/src/sio/sio_pc87310.c
@@ -106,7 +106,7 @@ lpt1_handler(pc87310_t *dev)
     }
 
     if (lpt_port)
-        lpt1_init(lpt_port);
+        lpt1_setup(lpt_port);
 
     lpt1_irq(lpt_irq);
 }
diff --git a/src/sio/sio_pc87311.c b/src/sio/sio_pc87311.c
index 1f38e6aa8..b560ef425 100644
--- a/src/sio/sio_pc87311.c
+++ b/src/sio/sio_pc87311.c
@@ -220,7 +220,7 @@ pc87311_lpt_handler(pc87311_t *dev)
         default:
             break;
     }
-    lpt1_init(dev->base);
+    lpt1_setup(dev->base);
     lpt1_irq(dev->irq);
     pc87311_log("PC87311-LPT: BASE %04x IRQ %01x\n", dev->base, dev->irq);
 }
diff --git a/src/sio/sio_pc87332.c b/src/sio/sio_pc87332.c
index f746306bd..d9fb0b211 100644
--- a/src/sio/sio_pc87332.c
+++ b/src/sio/sio_pc87332.c
@@ -77,7 +77,7 @@ lpt1_handler(pc87332_t *dev)
     }
 
     if (lpt_port)
-        lpt1_init(lpt_port);
+        lpt1_setup(lpt_port);
 
     lpt1_irq(lpt_irq);
 }
diff --git a/src/sio/sio_prime3b.c b/src/sio/sio_prime3b.c
index 2cadda2ab..1cc0be3aa 100644
--- a/src/sio/sio_prime3b.c
+++ b/src/sio/sio_prime3b.c
@@ -176,7 +176,7 @@ prime3b_lpt_handler(prime3b_t *dev)
 {
     uint16_t lpt_base = (ASR & 2) ? LPT_MDA_ADDR : (!(ASR & 1) ? LPT1_ADDR : LPT2_ADDR);
     lpt1_remove();
-    lpt1_init(lpt_base);
+    lpt1_setup(lpt_base);
     lpt1_irq(LPT1_IRQ);
     prime3b_log("Prime3B-LPT: Enabled with base %03x\n", lpt_base);
 }
diff --git a/src/sio/sio_prime3c.c b/src/sio/sio_prime3c.c
index e646a3653..f70f9f372 100644
--- a/src/sio/sio_prime3c.c
+++ b/src/sio/sio_prime3c.c
@@ -241,7 +241,7 @@ prime3c_lpt_handler(prime3c_t *dev)
     lpt1_remove();
     if (!(FUNCTION_SELECT & 0x03)) {
 
-        lpt1_init(LPT_BASE_ADDRESS << 2);
+        lpt1_setup(LPT_BASE_ADDRESS << 2);
         lpt1_irq(FDC_LPT_IRQ & 0xf);
         prime3c_log("Prime3C-LPT: BASE %04x IRQ %02x\n", LPT_BASE_ADDRESS << 2, FDC_LPT_IRQ & 0xf);
     }
diff --git a/src/sio/sio_um8663f.c b/src/sio/sio_um8663f.c
index 79cb37da4..54f12dda6 100644
--- a/src/sio/sio_um8663f.c
+++ b/src/sio/sio_um8663f.c
@@ -106,12 +106,12 @@ um8663f_lpt_handler(um8663f_t *dev)
     if (dev->regs[0] & 0x08) {
         switch ((dev->regs[1] >> 3) & 0x01) {
             case 0x01:
-                lpt1_init(LPT1_ADDR);
-                lpt1_irq(7);
+                lpt1_setup(LPT1_ADDR);
+                lpt1_irq(LPT1_IRQ);
                 break;
             case 0x00:
-                lpt1_init(LPT2_ADDR);
-                lpt1_irq(5);
+                lpt1_setup(LPT2_ADDR);
+                lpt1_irq(LPT2_IRQ);
                 break;
 
             default:
@@ -231,7 +231,7 @@ um8663f_reset(void *priv)
     serial_setup(dev->uart[1], COM2_ADDR, COM2_IRQ);
 
     lpt1_remove();
-    lpt1_init(LPT1_ADDR);
+    lpt1_setup(LPT1_ADDR);
 
     fdc_reset(dev->fdc);
     fdc_remove(dev->fdc);
diff --git a/src/sio/sio_um8669f.c b/src/sio/sio_um8669f.c
index b3d5259a2..6da9ef6e9 100644
--- a/src/sio/sio_um8669f.c
+++ b/src/sio/sio_um8669f.c
@@ -207,7 +207,7 @@ um8669f_pnp_config_changed(uint8_t ld, isapnp_device_config_t *config, void *pri
 
             if (config->activate && (config->io[0].base != ISAPNP_IO_DISABLED)) {
                 um8669f_log("UM8669F: LPT enabled at port %04X IRQ %d\n", config->io[0].base, config->irq[0].irq);
-                lpt1_init(config->io[0].base);
+                lpt1_setup(config->io[0].base);
             } else {
                 um8669f_log("UM8669F: LPT disabled\n");
             }
diff --git a/src/sio/sio_vt82c686.c b/src/sio/sio_vt82c686.c
index fa0bf3c63..0e874210d 100644
--- a/src/sio/sio_vt82c686.c
+++ b/src/sio/sio_vt82c686.c
@@ -86,7 +86,7 @@ vt82c686_lpt_handler(vt82c686_t *dev)
     lpt1_remove();
 
     if (((dev->regs[0x02] & 0x03) != 0x03) && !(dev->regs[0x0f] & 0x11) && (io_base >= 0x100) && (io_base <= io_mask))
-        lpt1_init(io_base);
+        lpt1_setup(io_base);
 
     if (dev->lpt_irq) {
         lpt1_irq(dev->lpt_irq);
diff --git a/src/sio/sio_w83787f.c b/src/sio/sio_w83787f.c
index ea5169afc..f4971ddce 100644
--- a/src/sio/sio_w83787f.c
+++ b/src/sio/sio_w83787f.c
@@ -197,7 +197,7 @@ w83787f_lpt_handler(w83787f_t *dev)
 
     lpt1_remove();
     if (enable) {
-        lpt1_init(addr);
+        lpt1_setup(addr);
         lpt1_irq(irq);
     }
 }
@@ -378,7 +378,7 @@ w83787f_reset(w83787f_t *dev)
     uint16_t hefere = dev->reg_init & 0x0100;
 
     lpt1_remove();
-    lpt1_init(LPT1_ADDR);
+    lpt1_setup(LPT1_ADDR);
     lpt1_irq(LPT1_IRQ);
 
     memset(dev->regs, 0, 0x2A);
diff --git a/src/sio/sio_w83877f.c b/src/sio/sio_w83877f.c
index 90a3dba1b..7c92d6e71 100644
--- a/src/sio/sio_w83877f.c
+++ b/src/sio/sio_w83877f.c
@@ -168,7 +168,7 @@ w83877f_lpt_handler(w83877f_t *dev)
 
     lpt1_remove();
     if (!(dev->regs[4] & 0x80) && (dev->regs[0x23] & 0xc0))
-        lpt1_init(make_port(dev, 0x23));
+        lpt1_setup(make_port(dev, 0x23));
 
     lpt_irq = 0xff;
 
diff --git a/src/sio/sio_w83977f.c b/src/sio/sio_w83977f.c
index 1d743cc64..fd177bc19 100644
--- a/src/sio/sio_w83977f.c
+++ b/src/sio/sio_w83977f.c
@@ -112,14 +112,14 @@ w83977f_lpt_handler(w83977f_t *dev)
         lpt2_remove();
 
         if ((dev->dev_regs[1][0x00] & 0x01) && (dev->regs[0x22] & 0x08) && (io_base >= 0x100) && (io_base <= io_mask))
-            lpt2_init(io_base);
+            lpt2_setup(io_base);
 
         lpt2_irq(dev->dev_regs[1][0x40] & 0x0f);
     } else {
         lpt1_remove();
 
         if ((dev->dev_regs[1][0x00] & 0x01) && (dev->regs[0x22] & 0x08) && (io_base >= 0x100) && (io_base <= io_mask))
-            lpt1_init(io_base);
+            lpt1_setup(io_base);
 
         lpt1_irq(dev->dev_regs[1][0x40] & 0x0f);
     }
diff --git a/src/sound/snd_lpt_dac.c b/src/sound/snd_lpt_dac.c
index 812a649a8..0462818a0 100644
--- a/src/sound/snd_lpt_dac.c
+++ b/src/sound/snd_lpt_dac.c
@@ -7,10 +7,10 @@
 #include "cpu.h"
 #include <86box/86box.h>
 #include <86box/filters.h>
+#include <86box/timer.h>
 #include <86box/lpt.h>
 #include <86box/machine.h>
 #include <86box/sound.h>
-#include <86box/timer.h>
 #include <86box/plat_unused.h>
 
 typedef struct lpt_dac_t {
diff --git a/src/sound/snd_lpt_dss.c b/src/sound/snd_lpt_dss.c
index 06160ce4c..875230518 100644
--- a/src/sound/snd_lpt_dss.c
+++ b/src/sound/snd_lpt_dss.c
@@ -7,10 +7,10 @@
 #include "cpu.h"
 #include <86box/86box.h>
 #include <86box/filters.h>
+#include <86box/timer.h>
 #include <86box/lpt.h>
 #include <86box/machine.h>
 #include <86box/sound.h>
-#include <86box/timer.h>
 #include <86box/plat_unused.h>
 
 typedef struct dss_t {
diff --git a/src/video/vid_colorplus.c b/src/video/vid_colorplus.c
index 958375f4e..6c66175c1 100644
--- a/src/video/vid_colorplus.c
+++ b/src/video/vid_colorplus.c
@@ -14,7 +14,7 @@
  *          Miran Grca, <mgrca8@gmail.com>
  *
  *          Copyright 2008-2018 Sarah Walker.
- *          Copyright 2016-2018 Miran Grca.
+ *          Copyright 2016-2025 Miran Grca.
  */
 #include <stdio.h>
 #include <stdint.h>
@@ -357,7 +357,7 @@ colorplus_standalone_init(UNUSED(const device_t *info))
     mem_mapping_add(&colorplus->cga.mapping, 0xb8000, 0x08000, colorplus_read, NULL, NULL, colorplus_write, NULL, NULL, NULL, MEM_MAPPING_EXTERNAL, colorplus);
     io_sethandler(0x03d0, 0x0010, colorplus_in, NULL, NULL, colorplus_out, NULL, NULL, colorplus);
 
-    lpt3_init(0x3BC);
+    lpt3_setup(LPT_MDA_ADDR);
 
     return colorplus;
 }
diff --git a/src/video/vid_hercules.c b/src/video/vid_hercules.c
index d50e8ba37..00374d08f 100644
--- a/src/video/vid_hercules.c
+++ b/src/video/vid_hercules.c
@@ -14,7 +14,7 @@
  *          Miran Grca, <mgrca8@gmail.com>
  *
  *          Copyright 2008-2019 Sarah Walker.
- *          Copyright 2016-2019 Miran Grca.
+ *          Copyright 2016-2025 Miran Grca.
  */
 #include <stdio.h>
 #include <stdint.h>
@@ -585,7 +585,7 @@ hercules_init(UNUSED(const device_t *info))
     video_inform(VIDEO_FLAG_TYPE_MDA, &timing_hercules);
 
     /* Force the LPT3 port to be enabled. */
-    lpt3_init(0x3BC);
+    lpt3_setup(LPT_MDA_ADDR);
 
     return dev;
 }
diff --git a/src/video/vid_herculesplus.c b/src/video/vid_herculesplus.c
index 99c614259..fb42c3022 100644
--- a/src/video/vid_herculesplus.c
+++ b/src/video/vid_herculesplus.c
@@ -14,7 +14,7 @@
  *          Miran Grca, <mgrca8@gmail.com>
  *
  *          Copyright 2008-2018 Sarah Walker.
- *          Copyright 2016-2018 Miran Grca.
+ *          Copyright 2016-2025 Miran Grca.
  */
 #include <stdio.h>
 #include <stdint.h>
@@ -23,8 +23,8 @@
 #include <wchar.h>
 #include <86box/86box.h>
 #include <86box/io.h>
-#include <86box/lpt.h>
 #include <86box/timer.h>
+#include <86box/lpt.h>
 #include <86box/pit.h>
 #include <86box/mem.h>
 #include <86box/rom.h>
@@ -670,7 +670,7 @@ herculesplus_init(UNUSED(const device_t *info))
     video_inform(VIDEO_FLAG_TYPE_MDA, &timing_herculesplus);
 
     /* Force the LPT3 port to be enabled. */
-    lpt3_init(0x3BC);
+    lpt3_setup(LPT_MDA_ADDR);
 
     return dev;
 }
diff --git a/src/video/vid_incolor.c b/src/video/vid_incolor.c
index 0abb4a6c2..d9b48f43a 100644
--- a/src/video/vid_incolor.c
+++ b/src/video/vid_incolor.c
@@ -14,7 +14,7 @@
  *          Miran Grca, <mgrca8@gmail.com>
  *
  *          Copyright 2008-2018 Sarah Walker.
- *          Copyright 2016-2018 Miran Grca.
+ *          Copyright 2016-2025 Miran Grca.
  */
 #include <stdio.h>
 #include <stdint.h>
@@ -1018,7 +1018,7 @@ incolor_init(UNUSED(const device_t *info))
     video_inform(VIDEO_FLAG_TYPE_MDA, &timing_incolor);
 
     /* Force the LPT3 port to be enabled. */
-    lpt3_init(0x3BC);
+    lpt3_setup(LPT_MDA_ADDR);
 
     return dev;
 }
diff --git a/src/video/vid_mda.c b/src/video/vid_mda.c
index 975b9ead1..66a0fbb71 100644
--- a/src/video/vid_mda.c
+++ b/src/video/vid_mda.c
@@ -14,7 +14,7 @@
  *          Miran Grca, <mgrca8@gmail.com>
  *
  *          Copyright 2008-2019 Sarah Walker.
- *          Copyright 2016-2019 Miran Grca.
+ *          Copyright 2016-2025 Miran Grca.
  */
 #include <stdio.h>
 #include <stdint.h>
@@ -322,7 +322,7 @@ mda_standalone_init(UNUSED(const device_t *info))
 
     mda_init(mda);
 
-    lpt3_init(0x3BC);
+    lpt3_setup(LPT_MDA_ADDR);
 
     return mda;
 }