diff --git a/src/include/86box/scsi_ncr5380.h b/src/include/86box/scsi_ncr5380.h
index 6453340ae..151a9873c 100644
--- a/src/include/86box/scsi_ncr5380.h
+++ b/src/include/86box/scsi_ncr5380.h
@@ -84,6 +84,7 @@ typedef struct ncr_t {
     int   (*dma_send_ext)(void *priv, void *ext_priv);
     int   (*dma_initiator_receive_ext)(void *priv, void *ext_priv);
     void  (*timer)(void *ext_priv, double period);
+    int   (*irq_ena)(void *priv, void *ext_priv, int state);
 
     scsi_bus_t scsibus;
 } ncr_t;
diff --git a/src/scsi/scsi_ncr5380.c b/src/scsi/scsi_ncr5380.c
index 102e637c4..2a29b070d 100644
--- a/src/scsi/scsi_ncr5380.c
+++ b/src/scsi/scsi_ncr5380.c
@@ -62,13 +62,9 @@ void
 ncr5380_irq(ncr_t *ncr, int set_irq)
 {
     if (set_irq) {
-        ncr->irq_state = 1;
-        ncr->isr |= STATUS_INT;
         if (ncr->irq != -1)
             picint(1 << ncr->irq);
     } else {
-        ncr->irq_state = 0;
-        ncr->isr &= ~STATUS_INT;
         if (ncr->irq != 1)
             picintc(1 << ncr->irq);
     }
@@ -104,7 +100,12 @@ ncr5380_reset(ncr_t *ncr)
     scsi_bus->data = 0;
     scsi_bus->command_issued = 0;
 
-    ncr5380_irq(ncr, 0);
+    if (ncr->irq_ena)
+        ncr->irq_ena(ncr, ncr->priv, 0);
+    else
+        ncr5380_irq(ncr, 0);
+
+    ncr->isr &= ~STATUS_INT;
 }
 
 uint32_t
@@ -164,7 +165,7 @@ ncr5380_write(uint16_t port, uint8_t val, ncr_t *ncr)
             if ((val & 0x80) && !(ncr->icr & 0x80)) {
                 ncr5380_log("Resetting the 5380\n");
                 ncr5380_reset(ncr);
-                ncr5380_irq(ncr, 1);
+                ncr->isr |= STATUS_INT;
             }
             ncr->icr = val;
             ncr5380_log("ICR WaitData=%d, ClearReq=%d.\n", scsi_bus->wait_data, scsi_bus->clear_req);
@@ -301,7 +302,7 @@ ncr5380_read(uint16_t port, ncr_t *ncr)
                 if (bus & BUS_MSG)
                     bus_state |= TCR_MSG;
                 if ((ncr->tcr & 7) != bus_state) {
-                    ncr5380_irq(ncr, 1);
+                    ncr->isr |= STATUS_INT;
                     ncr5380_log("IRQ issued\n");
                 }
             }
@@ -321,7 +322,12 @@ ncr5380_read(uint16_t port, ncr_t *ncr)
 
         case 7: /* reset Parity/Interrupt */
             ncr->isr &= ~(STATUS_BUSY_ERROR | 0x20);
-            ncr5380_irq(ncr, 0);
+            if (ncr->irq_ena)
+                ncr->irq_ena(ncr, ncr->priv, 0);
+            else
+                ncr5380_irq(ncr, 0);
+
+            ncr->isr &= ~STATUS_INT;
             ncr5380_log("Reset Interrupt\n");
             break;
 
diff --git a/src/scsi/scsi_ncr53c400.c b/src/scsi/scsi_ncr53c400.c
index 31a2de8b3..c8520d082 100644
--- a/src/scsi/scsi_ncr53c400.c
+++ b/src/scsi/scsi_ncr53c400.c
@@ -72,6 +72,7 @@ typedef struct ncr53c400_t {
     int8_t  type;
     uint8_t block_count;
     uint8_t status_ctrl;
+    uint8_t irq_config;
 
     int block_count_loaded;
 
@@ -103,6 +104,23 @@ ncr53c400_log(const char *fmt, ...)
 #    define ncr53c400_log(fmt, ...)
 #endif
 
+static int
+ncr53c400_irq_enable(void *priv, void *ext_priv, int state)
+{
+    ncr53c400_t *ncr400 = (ncr53c400_t *) ext_priv;
+    ncr_t *ncr = (ncr_t *) priv;
+
+    if (ncr->irq_state != state) {
+        ncr->irq_state = state;
+        ncr400->status_ctrl &= ~0x01;
+        ncr400->status_ctrl |= (state << 0);
+        ncr53c400_log("Status Control bit 4=%02x.\n", ncr400->status_ctrl);
+        if (ncr400->status_ctrl & 0x10)
+            ncr5380_irq(ncr, state);
+    }
+    return 1;
+}
+
 static void
 ncr53c400_timer_on_auto(void *ext_priv, double period)
 {
@@ -263,7 +281,8 @@ ncr53c400_read(uint32_t addr, void *priv)
                                 ncr->isr |= STATUS_END_OF_DMA;
                                 if (ncr->mode & MODE_ENA_EOP_INT) {
                                     ncr53c400_log("NCR read irq\n");
-                                    ncr5380_irq(ncr, 1);
+                                    ncr53c400_irq_enable(ncr, ncr400, 1);
+                                    ncr->isr |= STATUS_INT;
                                 }
                             } else if (!timer_is_enabled(&ncr400->timer)) {
                                 ncr53c400_log("Timer re-enabled.\n");
@@ -277,15 +296,16 @@ ncr53c400_read(uint32_t addr, void *priv)
             case 0x3980:
                 switch (addr) {
                     case 0x3980: /* status */
+                        if (ncr400->reset) {
+                            ncr400->reset = 0;
+                            ncr53c400_irq_enable(ncr, ncr400, 1);
+                        }
+
                         ret = ncr400->status_ctrl;
                         ncr53c400_log("NCR status ctrl read=%02x.\n", ncr400->status_ctrl & STATUS_BUFFER_NOT_READY);
                         if (!ncr400->busy)
                             ret |= STATUS_5380_ACCESSIBLE;
 
-                        if (ncr400->reset) {
-                            ncr400->reset = 0;
-                            ret |= 0x01;
-                        }
                         ncr53c400_log("NCR 53c400 status=%02x.\n", ret);
                         break;
 
@@ -295,10 +315,7 @@ ncr53c400_read(uint32_t addr, void *priv)
                         break;
 
                     case 0x3982: /* switch register read */
-                        if (ncr->irq != -1) {
-                            ret = 0xf8;
-                            ret += ncr->irq;
-                        }
+                        ret = ((ncr400->irq_config >> 5) & 7) | 0xf8;
                         ncr53c400_log("Switches read=%02x.\n", ret);
                         break;
 
@@ -519,7 +536,8 @@ ncr53c400_callback(void *priv)
                         ncr->isr |= STATUS_END_OF_DMA;
                         if (ncr->mode & MODE_ENA_EOP_INT) {
                             ncr53c400_log("NCR 53c400 write irq\n");
-                            ncr5380_irq(ncr, 1);
+                            ncr53c400_irq_enable(ncr, ncr400, 1);
+                            ncr->isr |= STATUS_INT;
                         }
                     }
                     break;
@@ -573,7 +591,8 @@ ncr53c400_callback(void *priv)
                             ncr->isr |= STATUS_END_OF_DMA;
                             if (ncr->mode & MODE_ENA_EOP_INT) {
                                 ncr53c400_log("NCR read irq\n");
-                                ncr5380_irq(ncr, 1);
+                                ncr53c400_irq_enable(ncr, ncr400, 1);
+                                ncr->isr |= STATUS_INT;
                             }
                         } else
                             timer_on_auto(&ncr400->timer, 1.0);
@@ -675,7 +694,8 @@ ncr53c400_init(const device_t *info)
     switch (ncr400->type) {
         case ROM_LCS6821N: /* Longshine LCS6821N */
             ncr400->rom_addr = device_get_config_hex20("bios_addr");
-            ncr->irq         = device_get_config_int("irq");
+            ncr400->irq_config = device_get_config_hex16("irq");
+            ncr->irq = (ncr400->irq_config >> 5) & 7;
 
             rom_init(&ncr400->bios_rom, LCS6821N_ROM,
                      ncr400->rom_addr, 0x4000, 0x3fff, 0, MEM_MAPPING_EXTERNAL);
@@ -689,7 +709,8 @@ ncr53c400_init(const device_t *info)
 
         case ROM_LS2000: /* Corel LS2000 */
             ncr400->rom_addr = device_get_config_hex20("bios_addr");
-            ncr->irq         = device_get_config_int("irq");
+            ncr400->irq_config = device_get_config_hex16("irq");
+            ncr->irq = (ncr400->irq_config >> 5) & 7;
 
             rom_init(&ncr400->bios_rom, COREL_LS2000_ROM,
                      ncr400->rom_addr, 0x4000, 0x3fff, 0, MEM_MAPPING_EXTERNAL);
@@ -702,7 +723,9 @@ ncr53c400_init(const device_t *info)
 
         case ROM_RT1000B: /* Rancho RT1000B/MC */
             ncr400->rom_addr = device_get_config_hex20("bios_addr");
-            ncr->irq         = device_get_config_int("irq");
+            ncr400->irq_config = device_get_config_hex16("irq");
+            ncr->irq = (ncr400->irq_config >> 5) & 7;
+
             if (info->flags & DEVICE_MCA) {
                 rom_init(&ncr400->bios_rom, RT1000B_820R_ROM,
                          0xd8000, 0x4000, 0x3fff, 0, MEM_MAPPING_EXTERNAL);
@@ -729,7 +752,8 @@ ncr53c400_init(const device_t *info)
         case ROM_T130B: /* Trantor T130B */
             ncr400->rom_addr = device_get_config_hex20("bios_addr");
             ncr400->base     = device_get_config_hex16("base");
-            ncr->irq     = device_get_config_int("irq");
+            ncr400->irq_config = device_get_config_hex16("irq");
+            ncr->irq = (ncr400->irq_config >> 5) & 7;
 
             if (ncr400->rom_addr > 0x00000) {
                 rom_init(&ncr400->bios_rom, T130B_ROM,
@@ -754,6 +778,7 @@ ncr53c400_init(const device_t *info)
     ncr->dma_send_ext               = NULL;
     ncr->dma_initiator_receive_ext  = NULL;
     ncr->timer                      = ncr53c400_timer_on_auto;
+    ncr->irq_ena                    = ncr53c400_irq_enable;
     scsi_bus->bus_device            = ncr->bus;
     scsi_bus->timer                 = ncr->timer;
     scsi_bus->priv                  = ncr->priv;
@@ -839,16 +864,16 @@ static const device_config_t ncr53c400_mmio_config[] = {
     {
         .name           = "irq",
         .description    = "IRQ",
-        .type           = CONFIG_SELECTION,
+        .type           = CONFIG_HEX16,
         .default_string = NULL,
-        .default_int    = 5,
+        .default_int    = 0xa0,
         .file_filter    = NULL,
         .spinner        = { 0 },
         .selection      = {
-            { .description = "None",  .value = -1 },
-            { .description = "IRQ 3", .value =  3 },
-            { .description = "IRQ 5", .value =  5 },
-            { .description = "IRQ 7", .value =  7 },
+            { .description = "IRQ 3", .value =  0x60 },
+            { .description = "IRQ 4", .value =  0x80 },
+            { .description = "IRQ 5", .value =  0xa0 },
+            { .description = "IRQ 7", .value =  0xe0 },
             { .description = ""                   }
         },
         .bios           = { { 0 } }
@@ -910,16 +935,16 @@ static const device_config_t rt1000b_config[] = {
     {
         .name           = "irq",
         .description    = "IRQ",
-        .type           = CONFIG_SELECTION,
+        .type           = CONFIG_HEX16,
         .default_string = NULL,
-        .default_int    = 5,
+        .default_int    = 0xa0,
         .file_filter    = NULL,
         .spinner        = { 0 },
         .selection      = {
-            { .description = "None",  .value = -1 },
-            { .description = "IRQ 3", .value =  3 },
-            { .description = "IRQ 5", .value =  5 },
-            { .description = "IRQ 7", .value =  7 },
+            { .description = "IRQ 3", .value =  0x60 },
+            { .description = "IRQ 4", .value =  0x80 },
+            { .description = "IRQ 5", .value =  0xa0 },
+            { .description = "IRQ 7", .value =  0xe0 },
             { .description = ""                   }
         },
         .bios           = { { 0 } }
@@ -931,16 +956,16 @@ static const device_config_t rt1000b_mc_config[] = {
     {
         .name           = "irq",
         .description    = "IRQ",
-        .type           = CONFIG_SELECTION,
+        .type           = CONFIG_HEX16,
         .default_string = NULL,
-        .default_int    = 5,
+        .default_int    = 0xa0,
         .file_filter    = NULL,
         .spinner        = { 0 },
         .selection      = {
-            { .description = "None",  .value = -1 },
-            { .description = "IRQ 3", .value =  3 },
-            { .description = "IRQ 5", .value =  5 },
-            { .description = "IRQ 7", .value =  7 },
+            { .description = "IRQ 3", .value =  0x60 },
+            { .description = "IRQ 4", .value =  0x80 },
+            { .description = "IRQ 5", .value =  0xa0 },
+            { .description = "IRQ 7", .value =  0xe0 },
             { .description = ""                   }
         },
         .bios           = { { 0 } }
@@ -987,16 +1012,16 @@ static const device_config_t t130b_config[] = {
     {
         .name           = "irq",
         .description    = "IRQ",
-        .type           = CONFIG_SELECTION,
+        .type           = CONFIG_HEX16,
         .default_string = NULL,
-        .default_int    = 5,
+        .default_int    = 0xa0,
         .file_filter    = NULL,
         .spinner        = { 0 },
         .selection      = {
-            { .description = "None",  .value = -1 },
-            { .description = "IRQ 3", .value =  3 },
-            { .description = "IRQ 5", .value =  5 },
-            { .description = "IRQ 7", .value =  7 },
+            { .description = "IRQ 3", .value =  0x60 },
+            { .description = "IRQ 4", .value =  0x80 },
+            { .description = "IRQ 5", .value =  0xa0 },
+            { .description = "IRQ 7", .value =  0xe0 },
             { .description = ""                   }
         },
         .bios           = { { 0 } }
diff --git a/src/scsi/scsi_t128.c b/src/scsi/scsi_t128.c
index 5b893dd70..2c2451cc7 100644
--- a/src/scsi/scsi_t128.c
+++ b/src/scsi/scsi_t128.c
@@ -27,7 +27,6 @@
 #define HAVE_STDARG_H
 #include <86box/86box.h>
 #include <86box/io.h>
-#include "cpu.h"
 #include <86box/timer.h>
 #include <86box/dma.h>
 #include <86box/pic.h>
@@ -41,6 +40,7 @@
 #include <86box/scsi_device.h>
 #include <86box/scsi_ncr5380.h>
 #include <86box/scsi_t128.h>
+#include "cpu.h"
 
 #define T128_ROM                "roms/scsi/ncr5380/trantor_t128_bios_v1.12.bin"
 
@@ -75,7 +75,7 @@ t128_write(uint32_t addr, uint8_t val, void *priv)
     if ((addr >= 0x1800) && (addr < 0x1880))
         t128->ext_ram[addr & 0x7f] = val;
     else if ((addr >= 0x1c00) && (addr < 0x1c20)) {
-        t128_log("T128 ctrl write=%02x, mode=%02x.\n", val, ncr->mode & MODE_DMA);
+        t128_log("T128 ctrl write=%02x, mode=%02x.\n", val & 0x10, ncr->mode & MODE_DMA);
         t128->ctrl = val;
     } else if ((addr >= 0x1d00) && (addr < 0x1e00))
         ncr5380_write((addr - 0x1d00) >> 5, val, ncr);
@@ -141,6 +141,7 @@ t128_read(uint32_t addr, void *priv)
                     if (ncr->mode & MODE_ENA_EOP_INT) {
                         t128_log("T128 read irq\n");
                         ncr5380_irq(ncr, 1);
+                        ncr->isr |= STATUS_INT;
                     }
                     scsi_bus->bus_out |= BUS_CD;
                     scsi_bus->tx_mode = PIO_TX_BUS;
@@ -298,6 +299,7 @@ t128_callback(void *priv)
                         if (ncr->mode & MODE_ENA_EOP_INT) {
                             t128_log("T128 write irq\n");
                             ncr5380_irq(ncr, 1);
+                            ncr->isr |= STATUS_INT;
                         }
                         scsi_bus->tx_mode = PIO_TX_BUS;
                         timer_stop(&t128->timer);
@@ -497,6 +499,7 @@ t128_init(const device_t *info)
     ncr->dma_send_ext               = t128_dma_send_ext;
     ncr->dma_initiator_receive_ext  = t128_dma_initiator_receive_ext;
     ncr->timer                      = t128_timer_on_auto;
+    ncr->irq_ena                    = NULL;
     scsi_bus->bus_device            = ncr->bus;
     scsi_bus->timer                 = ncr->timer;
     scsi_bus->priv                  = ncr->priv;
@@ -566,12 +569,13 @@ static const device_config_t t128_config[] = {
         .description    = "IRQ",
         .type           = CONFIG_SELECTION,
         .default_string = NULL,
-        .default_int    = 5,
+        .default_int    = -1,
         .file_filter    = NULL,
         .spinner        = { 0 },
         .selection      = {
             { .description = "None",  .value = -1 },
             { .description = "IRQ 3", .value = 3 },
+            { .description = "IRQ 4", .value = 4 },
             { .description = "IRQ 5", .value = 5 },
             { .description = "IRQ 7", .value = 7 },
             { .description = "IRQ 10", .value = 10 },