diff --git a/src/mouse_serial.c b/src/mouse_serial.c
index 04f23a8d9..3d410355a 100644
--- a/src/mouse_serial.c
+++ b/src/mouse_serial.c
@@ -57,21 +57,25 @@ sermouse_timer(void *priv)
 
     ms->delay = 0;
 
-    switch(ms->type) {
-	case SERMOUSE_TYPE_MICROSOFT:
-		/* This identifies a two-button Microsoft Serial mouse. */
-		serial_write_fifo(ms->serial, 'M', 1);
-		break;
+    if (ms->pos == -1)
+    {
+	    ms->pos = 0;
+	    switch(ms->type) {
+		case SERMOUSE_TYPE_MICROSOFT:
+			/* This identifies a two-button Microsoft Serial mouse. */
+			serial_write_fifo(ms->serial, 'M', 1);
+			break;
 
-	case SERMOUSE_TYPE_LOGITECH:
-		/* This identifies a two-button Logitech Serial mouse. */
-		serial_write_fifo(ms->serial, 'M', 1);
-		serial_write_fifo(ms->serial, '3', 1);
-		break;
+		case SERMOUSE_TYPE_LOGITECH:
+			/* This identifies a two-button Logitech Serial mouse. */
+			serial_write_fifo(ms->serial, 'M', 1);
+			serial_write_fifo(ms->serial, '3', 1);
+			break;
 
-	default:
-		/* No action needed. */
-		break;
+		default:
+			/* No action needed. */
+			break;
+	    }
     }
 }
 
@@ -83,6 +87,7 @@ sermouse_poll(int x, int y, int z, int b, void *priv)
     uint8_t buff[16];
     int len;
 
+    if (!(serial_ier(0) & 1)) return(1);
     if (!x && !y && b == ms->oldb) return(1);
 
     ms->oldb = b;
@@ -142,9 +147,12 @@ sermouse_poll(int x, int y, int z, int b, void *priv)
     pclog(" ] (%d)\n", len);
 #endif
 
-    /* Send the packet to the bottom-half of the attached port. */
-    for (b=0; b<len; b++)
-	serial_write_fifo(ms->serial, buff[b], 1);
+    if (!(serial_mctrl(0) & 0x10))
+    {
+	    /* Send the packet to the bottom-half of the attached port. */
+	    for (b=0; b<len; b++)
+		serial_write_fifo(ms->serial, buff[b], 1);
+    }
 
     return(0);
 }
diff --git a/src/pci.c b/src/pci.c
index 4218c587d..0dc20b68f 100644
--- a/src/pci.c
+++ b/src/pci.c
@@ -75,6 +75,19 @@ uint8_t elcr_read(uint16_t port, void *priv)
 	return elcr[port & 1];
 }
 
+void elcr_reset(void)
+{
+	int i = 0;
+
+	pic_reset();
+	elcr[0] = elcr[1] = 0;
+
+	for (i = 0; i < 32; i++)
+	{
+		pci_irq_active[i] = 0;
+	}
+}
+
 void pci_type2_write(uint16_t port, uint8_t val, void *priv);
 uint8_t pci_type2_read(uint16_t port, void *priv);
 
@@ -188,6 +201,8 @@ void pci_init(int type)
 
         PCI = 1;
 
+	elcr_reset();
+
 	io_sethandler(0x04d0, 0x0002, elcr_read, NULL, NULL, elcr_write, NULL, NULL,  NULL);
         
         if (type == PCI_CONFIG_TYPE_1)
diff --git a/src/pci.h b/src/pci.h
index 6a8778e0f..f1cecc952 100644
--- a/src/pci.h
+++ b/src/pci.h
@@ -1,3 +1,5 @@
+void elcr_reset(void);
+
 void pci_init(int type);
 void pci_slot(int card);
 void pci_add_specific(int card, uint8_t (*read)(int func, int addr, void *priv), void (*write)(int func, int addr, uint8_t val, void *priv), void *priv);
diff --git a/src/sio.c b/src/sio.c
index 03389a0ed..17e278fc4 100644
--- a/src/sio.c
+++ b/src/sio.c
@@ -169,6 +169,8 @@ void trc_reset(uint8_t val)
 
 		port_92_reset();
 		keyboard_at_reset();
+
+		elcr_reset();
 	}
 	resetx86();
 }