diff --git a/src/hdd/hdd_mfm_at.c b/src/hdd/hdd_mfm_at.c
index 966ed6021..67c0794fe 100644
--- a/src/hdd/hdd_mfm_at.c
+++ b/src/hdd/hdd_mfm_at.c
@@ -12,7 +12,7 @@
  *		based design. Most cards were WD1003-WA2 or -WAH, where the
  *		-WA2 cards had a floppy controller as well (to save space.)
  *
- * Version:	@(#)hdd_mfm_at.c	1.0.1	2017/09/17
+ * Version:	@(#)hdd_mfm_at.c	1.0.2	2017/09/23
  *
  * Authors:	Sarah Walker, <http://pcem-emulator.co.uk/>
  *		Miran Grca, <mgrca8@gmail.com>
@@ -31,13 +31,14 @@
 
 
 #define MFM_TIME		(TIMER_USEC*10)
+#define MFM_DEBUG		0
 
 #define STAT_ERR		0x01
 #define STAT_INDEX		0x02
-#define STAT_CORRECTED_DATA	0x04
+#define STAT_ECC		0x04
 #define STAT_DRQ		0x08	/* data request */
 #define STAT_DSC		0x10
-#define STAT_SEEK_COMPLETE	0x20
+#define STAT_WRFLT		0x20
 #define STAT_READY		0x40
 #define STAT_BUSY		0x80
 
@@ -59,94 +60,121 @@
 
 
 typedef struct {
-    int	present;
-    int	hdc_num;
-    int	spt, hpc;
-    int	tracks;
-    int	cfg_spt;
-    int	cfg_hpc;
-    int	current_cylinder;
+    int8_t	present,		/* drive is present */
+		hdc_num,		/* drive number in system */
+		steprate,		/* current servo step rate */
+		spt,			/* physical #sectors per track */
+		hpc,			/* physical #heads per cylinder */
+		pad;
+    int16_t	tracks;			/* physical #tracks per cylinder */
+
+    int8_t	cfg_spt,		/* configured #sectors per track */
+		cfg_hpc;		/* configured #heads per track */
+
+    int16_t	curcyl;			/* current track number */
 } mfm_drive_t;
 
 
 typedef struct {
-    uint8_t	status;
-    uint8_t	error;
-    uint8_t	secount,
-		sector,
-		head;
-    uint16_t	cylinder,
-		cylprecomp;
-    uint8_t	command;
-    uint8_t	fdisk;
+    uint8_t	precomp,		/* 1: precomp/error register */
+		error,
+		secount,		/* 2: sector count register */
+		sector,			/* 3: sector number */
+		head,			/* 6: head number + drive select */
+		command,		/* 7: command/status */
+		status,
+		fdisk;			/* 8: control register */
+    uint16_t	cylinder;		/* 4/5: cylinder LOW and HIGH */
 
-    int		pos;
-    int		drive_sel;
-    int		reset;
-    int		irqstat;
-    int		callback;
+    int8_t	reset,			/* controller in reset */
+		irqstat,		/* current IRQ status */
+		drvsel,			/* current selected drive */
+		pad;
 
-    uint16_t	buffer[256];
+    int		pos;			/* offset within data buffer */
+    int		callback;		/* callback delay timer */
 
-    mfm_drive_t drives[MFM_NUM];
+    uint16_t	buffer[256];		/* data buffer (16b wide) */
+
+    mfm_drive_t drives[MFM_NUM];	/* attached drives */
 } mfm_t;
 
 
 static __inline void irq_raise(mfm_t *mfm)
 {
-    if (!(mfm->fdisk&2))
-	picint(1 << 14);
+    /* If not already pending.. */
+    if (! mfm->irqstat) {
+	/* If enabled in the control register.. */
+	if (! (mfm->fdisk&0x02)) {
+		/* .. raise IRQ14. */
+		picint(1<<14);
+	}
 
-    mfm->irqstat=1;
+	/* Remember this. */
+	mfm->irqstat = 1;
+    }
 }
 
 
 static __inline void irq_lower(mfm_t *mfm)
 {
-    picintc(1 << 14);
+    /* If raised.. */
+    if (mfm->irqstat) {
+	/* If enabled in the control register.. */
+	if (! (mfm->fdisk&0x02)) {
+		/* .. drop IRQ14. */
+		picintc(1<<14);
+	}
+
+	/* Remember this. */
+	mfm->irqstat = 0;
+    }
 }
 
 
-static void
-irq_update(mfm_t *mfm)
-{
-    if (mfm->irqstat && !((pic2.pend|pic2.ins)&0x40) && !(mfm->fdisk & 2))
-		picint(1 << 14);
-}
-
-
-/* Return the sector offset for the current register values. */
+/*
+ * Return the sector offset for the current register values.
+ *
+ * According to the WD1002/WD1003 technical reference manual,
+ * this is not done entirely correct. It specifies that the
+ * parameters set with the SET_DRIVE_PARAMETERS command are
+ * to be used only for multi-sector operations, and that any
+ * such operation can only be executed AFTER these parameters
+ * have been set. This would imply that for regular single
+ * transfers, the controller uses (or, can use) the actual
+ * geometry information...
+ */
 static int
 get_sector(mfm_t *mfm, off64_t *addr)
 {
-    mfm_drive_t *drive = &mfm->drives[mfm->drive_sel];
+    mfm_drive_t *drive = &mfm->drives[mfm->drvsel];
 
-    if (drive->current_cylinder != mfm->cylinder) {
+    if (drive->curcyl != mfm->cylinder) {
 	pclog("WD1003(%d) sector: wrong cylinder\n");
 	return(1);
     }
 
     if (mfm->head > drive->cfg_hpc) {
 	pclog("WD1003(%d) get_sector: past end of configured heads\n",
-						mfm->drive_sel);
+							mfm->drvsel);
 	return(1);
     }
 
     if (mfm->sector >= drive->cfg_spt+1) {
 	pclog("WD1003(%d) get_sector: past end of configured sectors\n",
-							mfm->drive_sel);
+							mfm->drvsel);
 	return(1);
     }
 
 #if 1
     /* We should check this in the SET_DRIVE_PARAMETERS command!  --FvK */
     if (mfm->head > drive->hpc) {
-	pclog("WD1003(%d) get_sector: past end of heads\n", mfm->drive_sel);
+	pclog("WD1003(%d) get_sector: past end of heads\n", mfm->drvsel);
 	return(1);
     }
 
     if (mfm->sector >= drive->spt+1) {
-	pclog("WD1003(%d) get_sector: past end of sectors\n", mfm->drive_sel);
+	pclog("WD1003(%d) get_sector: past end of sectors\n", mfm->drvsel);
 	return(1);
     }
 #endif
@@ -162,22 +190,167 @@ get_sector(mfm_t *mfm, off64_t *addr)
 static void
 next_sector(mfm_t *mfm)
 {
-    mfm_drive_t *drive = &mfm->drives[mfm->drive_sel];
+    mfm_drive_t *drive = &mfm->drives[mfm->drvsel];
 
-    mfm->sector++;
-    if (mfm->sector == (drive->cfg_spt+1)) {
+    if (++mfm->sector == (drive->cfg_spt+1)) {
 	mfm->sector = 1;
-	mfm->head++;
-	if (mfm->head == drive->cfg_hpc) {
+	if (++mfm->head == drive->cfg_hpc) {
 		mfm->head = 0;
 		mfm->cylinder++;
-		if (drive->current_cylinder < drive->tracks)
-			drive->current_cylinder++;
+		if (drive->curcyl < drive->tracks)
+			drive->curcyl++;
 	}
     }
 }
 
 
+static void
+mfm_cmd(mfm_t *mfm, uint8_t val)
+{
+    mfm_drive_t *drive = &mfm->drives[mfm->drvsel];
+
+    if (! drive->present) {
+	/* This happens if sofware polls all drives. */
+	pclog("WD1003(%d) command %02x on non-present drive\n",
+					mfm->drvsel, val);
+	mfm->command = 0xff;
+	mfm->status = STAT_BUSY;
+	timer_process();
+	mfm->callback = 200*MFM_TIME;
+	timer_update_outstanding();
+
+	return;
+    }
+
+    irq_lower(mfm);
+    mfm->error = 0;
+
+    switch (val & 0xf0) {
+	case CMD_RESTORE:
+		drive->steprate = (val & 0x0f);
+#if MFM_DEBUG
+		pclog("WD1003(%d) restore, step=%d\n",
+			mfm->drvsel, drive->steprate);
+#endif
+		drive->curcyl = 0;
+		mfm->status = STAT_READY|STAT_DSC;
+		mfm->command = 0x00;
+		irq_raise(mfm);
+		break;
+
+	case CMD_SEEK:
+		drive->steprate = (val & 0x0f);
+		mfm->command = (val & 0xf0);
+		mfm->status = STAT_BUSY;
+		timer_process();
+		mfm->callback = 200*MFM_TIME;
+		timer_update_outstanding();
+		break;
+
+	default:
+		switch (val) {
+			case CMD_READ:
+			case CMD_READ+1:
+			case CMD_READ+2:
+			case CMD_READ+3:
+#if MFM_DEBUG
+				pclog("WD1003(%d) read, opt=%d\n",
+					mfm->drvsel, val&0x03);
+#endif
+				mfm->command = (val & 0xf0);
+				if (val & 2)
+					fatal("WD1003: READ with ECC\n");
+				mfm->status = STAT_BUSY;
+				timer_process();
+				mfm->callback = 200*MFM_TIME;
+				timer_update_outstanding();
+				break;
+
+			case CMD_WRITE:
+			case CMD_WRITE+1:
+			case CMD_WRITE+2:
+			case CMD_WRITE+3:
+#if MFM_DEBUG
+				pclog("WD1003(%d) write, opt=%d\n",
+					mfm->drvsel, val & 0x03);
+#endif
+				mfm->command = (val & 0xf0);
+				if (val & 2)
+					fatal("WD1003: WRITE with ECC\n");
+				mfm->status = STAT_DRQ|STAT_DSC;
+				mfm->pos = 0;
+				break;
+
+			case CMD_VERIFY:
+			case CMD_VERIFY+1:
+				mfm->command = (val & 0xfe);
+				mfm->status = STAT_BUSY;
+				timer_process();
+				mfm->callback = 200*MFM_TIME;
+				timer_update_outstanding();
+				break;
+
+			case CMD_FORMAT:
+				mfm->command = val;
+				mfm->status = STAT_DRQ|STAT_BUSY;
+				mfm->pos = 0;
+				break;
+
+			case CMD_DIAGNOSE:
+				mfm->command = val;
+				mfm->status = STAT_BUSY;
+				timer_process();
+				mfm->callback = 200*MFM_TIME;
+				timer_update_outstanding();
+				break;
+
+			case CMD_SET_PARAMETERS:
+				/*
+				 * NOTE:
+				 *
+				 * We currently just set these parameters, and
+				 * never bother to check if they "fit within"
+				 * the actual parameters, as determined by the
+				 * image loader.
+				 *
+				 * The difference in parameters is OK, and
+				 * occurs when the BIOS or operating system
+				 * decides to use a different translation
+				 * scheme, but either way, it SHOULD always
+				 * fit within the actual parameters!
+				 *
+				 * We SHOULD check that here!! --FvK
+				 */
+				if (drive->cfg_spt == 0) {
+					/* Only accept after RESET or DIAG. */
+					drive->cfg_spt = mfm->secount;
+					drive->cfg_hpc = mfm->head+1;
+					pclog("WD1003(%d) parameters: tracks=%d, spt=%i, hpc=%i\n",
+						mfm->drvsel, drive->tracks,
+						drive->cfg_spt, drive->cfg_hpc);
+				} else {
+					pclog("WD1003(%d) parameters: tracks=%d,spt=%i,hpc=%i (IGNORED)\n",
+						mfm->drvsel, drive->tracks,
+						drive->cfg_spt, drive->cfg_hpc);
+				}
+				mfm->command = 0x00;
+				mfm->status = STAT_READY|STAT_DSC;
+				mfm->error = 1;
+				irq_raise(mfm);
+				break;
+
+			default:
+				pclog("WD1003: bad command %02X\n", val);
+				mfm->status = STAT_BUSY;
+				timer_process();
+				mfm->callback = 200*MFM_TIME;
+				timer_update_outstanding();
+				break;
+		}
+    }
+}
+
+
 static void
 mfm_writew(uint16_t port, uint16_t val, void *priv)
 {
@@ -201,150 +374,52 @@ mfm_write(uint16_t port, uint8_t val, void *priv)
 {
     mfm_t *mfm = (mfm_t *)priv;
 
-#if 0
+#if MFM_DEBUG > 1
     pclog("WD1003 write(%04x, %02x)\n", port, val);
 #endif
     switch (port) {
-	case 0x1f0:	/* data */
+	case 0x01f0:	/* data */
 		mfm_writew(port, val | (val << 8), priv);
 		return;
 
-	case 0x1f1:	/* write precompenstation */
-		mfm->cylprecomp = val;
+	case 0x01f1:	/* write precompenstation */
+		mfm->precomp = val;
 		return;
 
-	case 0x1f2:	/* sector count */
+	case 0x01f2:	/* sector count */
 		mfm->secount = val;
 		return;
 
-	case 0x1f3:	/* sector */
+	case 0x01f3:	/* sector */
 		mfm->sector = val;
 		return;
 
-	case 0x1f4:	/* cylinder low */
+	case 0x01f4:	/* cylinder low */
 		mfm->cylinder = (mfm->cylinder & 0xff00) | val;
 		return;
 
-	case 0x1f5:	/* cylinder high */
+	case 0x01f5:	/* cylinder high */
 		mfm->cylinder = (mfm->cylinder & 0xff) | (val << 8);
 		return;
 
-	case 0x1f6:	/* drive/head */
+	case 0x01f6:	/* drive/head */
 		mfm->head = val & 0xF;
-		mfm->drive_sel = (val & 0x10) ? 1 : 0;
-		if (mfm->drives[mfm->drive_sel].present)
-			mfm->status = STAT_READY | STAT_DSC;
+		mfm->drvsel = (val & 0x10) ? 1 : 0;
+		if (mfm->drives[mfm->drvsel].present)
+			mfm->status = STAT_READY|STAT_DSC;
 		  else
 			mfm->status = 0;
 		return;
 
-	case 0x1f7:	/* command register */
-		if (! mfm->drives[mfm->drive_sel].present) {
-			/*
-			 * We should not panic on this, as some systems
-			 * (like several old UNIX systems like Microport
-			 * SystemV/AT) poll both drives...
-			 */
-			pclog("WD1003(%d) command %02x on non-present drive\n",
-							mfm->drive_sel, val);
-			mfm->command = 0xff;
-			mfm->status = STAT_BUSY;
-			timer_process();
-			mfm->callback = 200*MFM_TIME;
-			timer_update_outstanding();
-			return;
-		}
-
-		irq_lower(mfm);
-		mfm->command = val;
-		mfm->error = 0;
-
-		switch (val & 0xf0) {
-			case CMD_RESTORE:
-				mfm->command &= ~0x0f; /* mask off step rate */
-				mfm->status = STAT_BUSY;
-				timer_process();
-				mfm->callback = 200*MFM_TIME;
-				timer_update_outstanding();
-				break;
-
-			case CMD_SEEK:
-				mfm->command &= ~0x0f; /* mask off step rate */
-				mfm->status = STAT_BUSY;
-				timer_process();
-				mfm->callback = 200*MFM_TIME;
-				timer_update_outstanding();
-				break;
-
-			default:
-				switch (val) {
-					case CMD_READ:
-					case CMD_READ+1:
-					case CMD_READ+2:
-					case CMD_READ+3:
-						mfm->command &= ~0x03;
-						if (val & 2)
-						    fatal("WD1003: READ with ECC\n");
-						mfm->status = STAT_BUSY;
-						timer_process();
-						mfm->callback = 200*MFM_TIME;
-						timer_update_outstanding();
-						break;
-
-					case CMD_WRITE:
-					case CMD_WRITE+1:
-					case CMD_WRITE+2:
-					case CMD_WRITE+3:
-						mfm->command &= ~0x03;
-						if (val & 2)
-						    fatal("WD1003: WRITE with ECC\n");
-						mfm->status = STAT_DRQ|STAT_DSC;
-						mfm->pos = 0;
-						break;
-
-					case CMD_VERIFY:
-					case CMD_VERIFY+1:
-						mfm->command &= ~0x01;
-						mfm->status = STAT_BUSY;
-						timer_process();
-						mfm->callback = 200 * MFM_TIME;
-						timer_update_outstanding();
-						break;
-
-					case CMD_FORMAT:
-						mfm->status =STAT_DRQ|STAT_BUSY;
-						mfm->pos = 0;
-						break;
-
-					case CMD_SET_PARAMETERS:
-						mfm->status = STAT_BUSY;
-						timer_process();
-						mfm->callback = 30*MFM_TIME;
-						timer_update_outstanding();
-						break;
-
-					case CMD_DIAGNOSE:
-						mfm->status = STAT_BUSY;
-						timer_process();
-						mfm->callback = 200*MFM_TIME;
-						timer_update_outstanding();
-						break;
-
-					default:
-						pclog("WD1003: bad command %02X\n", val);
-						mfm->status = STAT_BUSY;
-						timer_process();
-						mfm->callback = 200*MFM_TIME;
-						timer_update_outstanding();
-						break;
-				}
-		}
+	case 0x01f7:	/* command register */
+		mfm_cmd(mfm, val);
 		break;
 
-	case 0x3f6:	/* device control */
+	case 0x03f6:	/* device control */
+		val &= 0x0f;
 		if ((mfm->fdisk & 0x04) && !(val & 0x04)) {
-			mfm->reset = 1;
 			mfm->status = STAT_BUSY;
+			mfm->reset = 1;
 			timer_process();
 			mfm->callback = 500*MFM_TIME;
 			timer_update_outstanding();
@@ -357,9 +432,7 @@ mfm_write(uint16_t port, uint8_t val, void *priv)
 			timer_process();
 			timer_update_outstanding();
 		}
-
 		mfm->fdisk = val;
-		irq_update(mfm);
 		break;
     }
 }
@@ -374,8 +447,8 @@ mfm_readw(uint16_t port, void *priv)
     ret = mfm->buffer[mfm->pos >> 1];
     mfm->pos += 2;
     if (mfm->pos >= 512) {
-	mfm->pos=0;
-	mfm->status = STAT_READY | STAT_DSC;
+	mfm->pos = 0;
+	mfm->status = STAT_READY|STAT_DSC;
 	if (mfm->command == CMD_READ) {
 		mfm->secount = (mfm->secount - 1) & 0xff;
 		if (mfm->secount) {
@@ -385,7 +458,7 @@ mfm_readw(uint16_t port, void *priv)
 			mfm->callback = 6*MFM_TIME;
 			timer_update_outstanding();
 		} else {
-			update_status_bar_icon(SB_HDD | HDD_BUS_MFM, 0);
+			update_status_bar_icon(SB_HDD|HDD_BUS_MFM, 0);
 		}
 	}
     }
@@ -401,35 +474,35 @@ mfm_read(uint16_t port, void *priv)
     uint8_t ret = 0xff;
 
     switch (port) {
-	case 0x1f0:	/* data */
+	case 0x01f0:	/* data */
 		ret = mfm_readw(port, mfm) & 0xff;
 		break;
 
-	case 0x1f1:	/* error */
+	case 0x01f1:	/* error */
 		ret = mfm->error;
 		break;
 
-	case 0x1f2:	/* sector count */
+	case 0x01f2:	/* sector count */
 		ret = mfm->secount;
 		break;
 
-	case 0x1f3:	/* sector */
+	case 0x01f3:	/* sector */
 		ret = mfm->sector;
 		break;
 
-	case 0x1f4:	/* CYlinder low */
+	case 0x01f4:	/* CYlinder low */
 		ret = (uint8_t)(mfm->cylinder&0xff);
 		break;
 
-	case 0x1f5:	/* Cylinder high */
+	case 0x01f5:	/* Cylinder high */
 		ret = (uint8_t)(mfm->cylinder>>8);
 		break;
 
-	case 0x1f6:	/* drive/head */
-		ret = (uint8_t)(0xa0 | mfm->head | (mfm->drive_sel?0x10:0));
+	case 0x01f6:	/* drive/head */
+		ret = (uint8_t)(0xa0 | mfm->head | (mfm->drvsel?0x10:0));
 		break;
 
-	case 0x1f7:	/* Status */
+	case 0x01f7:	/* Status */
 		irq_lower(mfm);
 		ret = mfm->status;
 		break;
@@ -437,7 +510,7 @@ mfm_read(uint16_t port, void *priv)
 	default:
 		break;
     }
-#if 0
+#if MFM_DEBUG > 1
     pclog("WD1003 read(%04x) = %02x\n", port, ret);
 #endif
 
@@ -448,12 +521,16 @@ mfm_read(uint16_t port, void *priv)
 static void
 do_seek(mfm_t *mfm)
 {
-    mfm_drive_t *drive = &mfm->drives[mfm->drive_sel];
+    mfm_drive_t *drive = &mfm->drives[mfm->drvsel];
 
+#if MFM_DEBUG
+    pclog("WD1003(%d) seek(%d) max=%d\n",
+	mfm->drvsel,mfm->cylinder,drive->tracks);
+#endif
     if (mfm->cylinder < drive->tracks)
-	drive->current_cylinder = mfm->cylinder;
+	drive->curcyl = mfm->cylinder;
       else
-	drive->current_cylinder = drive->tracks-1;
+	drive->curcyl = drive->tracks-1;
 }
 
 
@@ -461,145 +538,138 @@ static void
 do_callback(void *priv)
 {
     mfm_t *mfm = (mfm_t *)priv;
-    mfm_drive_t *drive = &mfm->drives[mfm->drive_sel];
+    mfm_drive_t *drive = &mfm->drives[mfm->drvsel];
     off64_t addr;
 
     mfm->callback = 0;
     if (mfm->reset) {
-	mfm->status = STAT_READY | STAT_DSC;
+#if MFM_DEBUG
+	pclog("WD1003(%d) reset\n", mfm->drvsel);
+#endif
+	mfm->status = STAT_READY|STAT_DSC;
 	mfm->error = 1;
 	mfm->secount = 1;
 	mfm->sector = 1;
 	mfm->head = 0;
 	mfm->cylinder = 0;
-	drive->cfg_spt = 0;	/* we need new parameters after reset! */
+
+	drive->steprate = 0x0f;		/* default steprate */
+	drive->cfg_spt = 0;		/* need new parameters */
+
 	mfm->reset = 0;
+
+	update_status_bar_icon(SB_HDD|HDD_BUS_MFM, 0);
+
 	return;
     }
 
     switch (mfm->command) {
-	case CMD_RESTORE:
-		drive->current_cylinder = 0;
-		mfm->status = STAT_READY | STAT_DSC;
-		irq_raise(mfm);
-		break;
-
 	case CMD_SEEK:
+#if MFM_DEBUG
+		pclog("WD1003(%d) seek, step=%d\n",
+			mfm->drvsel, drive->steprate);
+#endif
 		do_seek(mfm);
-		mfm->status = STAT_READY | STAT_DSC;
+		mfm->status = STAT_READY|STAT_DSC;
 		irq_raise(mfm);
 		break;
 
 	case CMD_READ:
+#if MFM_DEBUG
+		pclog("WD1003(%d) read(%d,%d,%d)\n",
+			mfm->drvsel, mfm->cylinder, mfm->head, mfm->sector);
+#endif
 		do_seek(mfm);
 		if (get_sector(mfm, &addr)) {
 			mfm->error = ERR_ID_NOT_FOUND;
-			mfm->status = STAT_READY | STAT_DSC | STAT_ERR;
+			mfm->status = STAT_READY|STAT_DSC|STAT_ERR;
 			irq_raise(mfm);
 			break;
 		}
 
-		hdd_image_read(drive->hdc_num, addr, 1,(uint8_t *)mfm->buffer);
+		hdd_image_read(drive->hdc_num, addr, 1, (uint8_t *)mfm->buffer);
 
 		mfm->pos = 0;
-		mfm->status = STAT_DRQ | STAT_READY | STAT_DSC;
+		mfm->status = STAT_DRQ|STAT_READY|STAT_DSC;
 		irq_raise(mfm);
-		update_status_bar_icon(SB_HDD | HDD_BUS_MFM, 1);
+		update_status_bar_icon(SB_HDD|HDD_BUS_MFM, 1);
 		break;
 
 	case CMD_WRITE:
+#if MFM_DEBUG
+		pclog("WD1003(%d) write(%d,%d,%d)\n",
+			mfm->drvsel, mfm->cylinder, mfm->head, mfm->sector);
+#endif
 		do_seek(mfm);
 		if (get_sector(mfm, &addr)) {
 			mfm->error = ERR_ID_NOT_FOUND;
-			mfm->status = STAT_READY | STAT_DSC | STAT_ERR;
+			mfm->status = STAT_READY|STAT_DSC|STAT_ERR;
 			irq_raise(mfm);
 			break;
 		}
 
 		hdd_image_write(drive->hdc_num, addr, 1,(uint8_t *)mfm->buffer);
 
-		irq_raise(mfm);
+		mfm->status = STAT_READY|STAT_DSC;
 		mfm->secount = (mfm->secount - 1) & 0xff;
 		if (mfm->secount) {
-			mfm->status = STAT_DRQ | STAT_READY | STAT_DSC;
+			/* More sectors to do.. */
+			mfm->status |= STAT_DRQ;
 			mfm->pos = 0;
 			next_sector(mfm);
-			update_status_bar_icon(SB_HDD | HDD_BUS_MFM, 1);
+			update_status_bar_icon(SB_HDD|HDD_BUS_MFM, 1);
 		} else {
-			mfm->status = STAT_READY | STAT_DSC;
-			update_status_bar_icon(SB_HDD | HDD_BUS_MFM, 0);
+			update_status_bar_icon(SB_HDD|HDD_BUS_MFM, 0);
 		}
+		irq_raise(mfm);
 		break;
 
 	case CMD_VERIFY:
+#if MFM_DEBUG
+		pclog("WD1003(%d) verify(%d,%d,%d)\n",
+			mfm->drvsel, mfm->cylinder, mfm->head, mfm->sector);
+#endif
 		do_seek(mfm);
 		mfm->pos = 0;
-		mfm->status = STAT_READY | STAT_DSC;
+		mfm->status = STAT_READY|STAT_DSC;
 		irq_raise(mfm);
-		update_status_bar_icon(SB_HDD | HDD_BUS_MFM, 1);
+		update_status_bar_icon(SB_HDD|HDD_BUS_MFM, 1);
 		break;
 
 	case CMD_FORMAT:
+#if MFM_DEBUG
+		pclog("WD1003(%d) format(%d,%d)\n",
+			mfm->drvsel, mfm->cylinder, mfm->head);
+#endif
 		do_seek(mfm);
 		if (get_sector(mfm, &addr)) {
 			mfm->error = ERR_ID_NOT_FOUND;
-			mfm->status = STAT_READY | STAT_DSC | STAT_ERR;
+			mfm->status = STAT_READY|STAT_DSC|STAT_ERR;
 			irq_raise(mfm);
 			break;
 		}
 
 		hdd_image_zero(drive->hdc_num, addr, mfm->secount);
 
-		mfm->status = STAT_READY | STAT_DSC;
+		mfm->status = STAT_READY|STAT_DSC;
 		irq_raise(mfm);
-		update_status_bar_icon(SB_HDD | HDD_BUS_MFM, 1);
+		update_status_bar_icon(SB_HDD|HDD_BUS_MFM, 1);
 		break;
 
 	case CMD_DIAGNOSE:
-		mfm->error = 1; /*No error detected*/
-		mfm->status = STAT_READY | STAT_DSC;
-		irq_raise(mfm);
-		break;
-
-	case CMD_SET_PARAMETERS: /* Initialize Drive Parameters */
-		/*
-		 * NOTE:
-		 *
-		 * We currently just set these parameters, and never
-		 * bother to check if they "fit within" the actual
-		 * parameters, as determined by the image loader.
-		 *
-		 * The difference in parameters is OK, and occurs
-		 * when the BIOS or operating system decides to use
-		 * a different translation scheme, but either way,
-		 * it SHOULD always fit within the actual parameters!
-		 *
-		 * We SHOULD check that here!!  --FvK
-		 */
-		if (drive->cfg_spt == 0) {
-			drive->cfg_spt = mfm->secount;
-			drive->cfg_hpc = mfm->head+1;
-			pclog("WD1003(%d) parameters: tracks=%d, spt=%i, hpc=%i\n",
-				mfm->drive_sel,drive->tracks,
-				drive->cfg_spt,drive->cfg_hpc);
-		} else {
-			/*
-			 * For debugging the weirdness that happens
-			 * while trying to install Microport SysV/AT,
-			 * which issues several calls with changing
-			 * parameters.  --FvK
-			 */
-			pclog("WD1003(%d) parameters: tracks=%d,spt=%i,hpc=%i (IGNORED)\n",
-				mfm->drive_sel,drive->tracks,drive->cfg_spt,drive->cfg_hpc);
-		}
-		mfm->status = STAT_READY | STAT_DSC;
+#if MFM_DEBUG
+		pclog("WD1003(%d) diag\n", mfm->drvsel);
+#endif
+		drive->steprate = 0x0f;
+		mfm->error = 1;
+		mfm->status = STAT_READY|STAT_DSC;
 		irq_raise(mfm);
 		break;
 
 	default:
 		pclog("WD1003(%d) callback on unknown command %02x\n",
-					mfm->drive_sel, mfm->command);
-		mfm->status = STAT_READY | STAT_ERR | STAT_DSC;
+					mfm->drvsel, mfm->command);
+		mfm->status = STAT_READY|STAT_ERR|STAT_DSC;
 		mfm->error = ERR_ABRT;
 		irq_raise(mfm);
 		break;
@@ -614,6 +684,7 @@ loadhd(mfm_t *mfm, int c, int d, const wchar_t *fn)
 
     if (! hdd_image_load(d)) {
 	drive->present = 0;
+
 	return;
     }
 
@@ -638,14 +709,16 @@ mfm_init(void)
     c = 0;
     for (d=0; d<HDC_NUM; d++) {
 	if ((hdc[d].bus == HDD_BUS_MFM) && (hdc[d].mfm_channel < MFM_NUM)) {
-		pclog("WD1003(%d): (%S) on disk %d\n", c, hdc[d].fn, d);
 		loadhd(mfm, hdc[d].mfm_channel, d, hdc[d].fn);
-		c++;
-		if (c >= MFM_NUM)  break;
+
+		pclog("WD1003(%d): (%S) geometry %d/%d/%d\n", c, hdc[d].fn,
+			(int)hdc[d].tracks, (int)hdc[d].hpc, (int)hdc[d].spt);
+
+		if (++c >= MFM_NUM) break;
 	}
     }
 
-    mfm->status = STAT_READY | STAT_DSC;	/* drive is ready */
+    mfm->status = STAT_READY|STAT_DSC;		/* drive is ready */
     mfm->error = 1;				/* no errors */
 
     io_sethandler(0x01f0, 1,
@@ -657,6 +730,8 @@ mfm_init(void)
 
     timer_add(do_callback, &mfm->callback, &mfm->callback, mfm);	
 
+    update_status_bar_icon(SB_HDD|HDD_BUS_MFM, 0);
+
     return(mfm);
 }
 
@@ -674,6 +749,8 @@ mfm_close(void *priv)
     }
 
     free(mfm);
+
+    update_status_bar_icon(SB_HDD|HDD_BUS_MFM, 0);
 }