MSX floppy drives

MSX Floppy disks

Replacing a broken drive, add a second drive, use a PC floppy disk drive.

Floppy disk drives are, next to powersupplies and keyboards, the most volatile MSX hardware components.In the past, getting replacement drives was possible, although expensive. Many types with all kind of connectors were used. A good example is the drive in the TurboR: a very special type and connector.
The 360 Kb and 720 Kb floppy drive is nowadays very rare and very expensive compared to the HD 1.44 Mb floppy drives used in PC’s. To fix a faulty floppy drive with another secondhand 360 Kb or 720kB or with a new PC drive you need some information.

Here are some articles that may help you:

Modification guides (in dutch alas) written by Bas Kornalijnslijper.
Inbouw 720 kB diskdrive in Philips VG 8235/00
Inbouw 720 kB diskdrive in Philips VG 8235/20
Reparatie Diskdrive Philips NMS 8245
Diskdrive vervangen Philips NMS 8245
Diskdrive vervangen Philips NMS 8250/55/80
Philips VY 0010 ombouwen naar 720 kB
Diskdrive vervangen Sony HB-F700P/D/F/S
Diskdrive vervangen Sony HBD-30W
Diskdrive vervangen Sony HB-F1XD(J) & HB-F1XV
Diskdrive vervangen Sanyo Wavy PHC-70FD(2)
Diskdrive repareren Panasonic FS-A1F & FS-A1FM
Diskdrive vervangen Panasonic FS-FD1A
Reparatie Panasonic diskdrive
Reparatie Enkelzijdige diskdrive
Modificatie Dubbelzijdige diskdrive

Replace a MSX turboR Diskdrive with a PC Drive. by Erik Luppes
Replace a Panasonic FS-A1F Diskdrive with a PC Drive by Erik Luppes

Add a second drive to the turboR, repair etc (tested working instructions)
Replace the belt in a turboR
(belt is 48mmX3mm,
Part N° DFWV75C0009
Part Name: Round Belt, Rubbor, 3mm
Item N° S01-4-Y2000 (FW-U1P501J)
MatsuhitaElectric)
The belt in the Phips VG8235 and NMS8245 is the type label BF60 in dutch electronic shops.

Portugese description and circuit diagram how to place a PC drive in a turboR by Luciano Sturaro.

Add a second drive to the SVI.738 X’Press german
Add a second drive to HB-F700P/D and Philips MSX in dutch , in english
Add a second drive to the HBD-50
Floppy configuration guide
How to replace the drive in a VG8245 (by Ag0ny, from www.aamsx.org)
Connect a PC floppy drive to a Sany Wavyy 70FDD (spanish version)
Connect a PC floppy drive to a Sany Wavyy 70FDD (english version)
Connect a 3 inch drive to a SVI 738 Xpress

Add a Teac PC drive to the Yamaha FDD-051
Replace the drive in the NMS8245 with a PC floppy disk drive
Replace a MSX floppy disk drive with a PC floppy disk drive
Replace the drive in the NMS8245 with a PC floppy disk drive
Replace a MSX floppy disk drive with a PC floppy disk drive (based on information by Hans Oranje)
Replace the main floppy drive in the NMS8250 with a PC drive (picture)

Floppy Disk Drives

Here are the specs of some 5.25 and 3.5 inch floppy disk drives ripped out of a PDF document. Made by Rene van Belzen

Written by Avatar, adapted, enhanced and corrected by HansO. Use at your own risk!

Here is a table with info about all pins configuration known. Below are the instructions to put a PC drive on the Sanyo Wavy70FD2. With this information, you will be able to put ANY common PC drive on ANY MSX. Some MSX uses different configurations which is the case of Philips, SpectraVideo and turbo R. In the MSX-Faq and others sites you will find information about those adaptations, then, I will not repeat them here. If your MSX have a 34-pin cable, just follow the Sanyo adaptation below. You will be warned in what aspects the Sanyo adaptations differs from others MSX 34-pins adaptations. Almost aways, you just need to plug the MSX pin to the PC pin that have the same function. Your user or service manual manual must show you your pin configuration. It’s not hard! Read all text below and you will learn how to help yourself.

Pin

VG8230 NMS8245

Internal Connector

VG8230 NMS8245

Floppy Connector

SVI 738

turbo R

PC Laptop 26

MSX 34-pins

Computer Connector

MSX 34-pins

Floppy Connector

PC 34-pins

Floppy Connector

Sanyo Wavy 70FD2

Internal Connector

Pin

1

Index

Not connected

+12V

+5V

+5V MSX=Power Supply

In Use *

Gnd

Gnd

Not connected

1

2

Direction

Not connected

+5V

+5V

Index MSX=8

Disk Change *

Reserved

Density 1

Not connected

2

3

Step

Return

+5V

Not connected

+5V

Gnd

Gnd

Gnd

Not connected

3

4

Write Data

In Use

Index

+5V

Drive Select 0 MSX=10

Not connected

Reserved

Density 2

Not connected

4

5

Write Gate

Return

Drive Select 1

+5V

+5V

Gnd

Gnd

Gnd

Not connected

5

6

Disk Select 0

Drive Select 3

Direction

Ready

Disk Change MSX=Not used

Disk Select 3 *

Drive Select 3

Reserved

Not connected

6

7

Disk Select 1

Return

Step

Gnd

Reserved

Gnd

Gnd

Gnd

+5V

7

8

Side Select ***

Index

Write Data

Gnd

Ready MSX=34

Index

Index

Index

Index

8

9

Not connected

Return

Write Gate

Side Selection

Media MSX=Not used

Gnd

Gnd

Gnd

+5V

9

10

Motor On

Drive Select 0

Track 0

Gnd

Motor On MSX=16

Disk Select 0

Disk Select 0

Disk Select 0

Disk Select 0

10

11

Gnd

Return

Write Protected

Read Data

Density Select MSX=Not used

Gnd

Gnd

Gnd

+5V

11

12

Track 0

Drive Select 1

Read Data

Write Protected

Direction MSX=18

Disk Select 1

Disk Select 1

Disk Select 1

Disk Select 1

12

13

Write Protected

Return

Side Select

Track 0

In Use MSX=Not used

Gnd

Gnd

Gnd

Gnd

13

14

Read Data

Drive Select 2

+12V

Write Gate

Step MSX=20

Disk Select 2 *

Disk Select 2

Reserved

Not connected

14

15

None

Return

+12V

Gnd

0V MSX=Power supply

Gnd

Gnd

Gnd

Gnd

15

16

None

Motor On

+5V

Write Data

Write Data MSX=22

Motor On

Motor On

Motor On

Motor On

16

17

None

Return

Drive Select 0

Gnd

0V

Gnd

Gnd

Gnd

Gnd

17

18

None

Direction

Motor On

Step

Write Gate MSX=24

Direction

Direction

Direction

Direction

18

19

None

Return

Ready

Direction

0V

Gnd

Gnd

Gnd

Gnd

19

20

None

Step

Gnd

Motor On

Track 0 MSX=26

Step

Step

Step

Step

20

21

None

Return

Gnd

Not connected

0V

Gnd

Gnd

Gnd

Gnd

21

22

None

Write Data

Gnd

Drive Selection

Write Protected MSX=28

Write Data

Write Data

Write Data

Write Data

22

23

None

Return

Gnd

Index

0V

Gnd

Gnd

Gnd

Gnd

23

24

None

Write Gate

Gnd

Disk Change ?

Read Data MSX=30

Write Gate

Write Gate

Write Gate

Write Gate

24

25

None

Return

Gnd

None

0V

Gnd

Gnd

Gnd

Gnd

25

26

None

Track 0

None

t

Side 1 Select MSX=32

Track 0

Track 0

Track 0

Track 0

26

27

None

Return

None

None

None

Gnd

Gnd

Gnd

Gnd

27

28

None

Write Protected

None

None

None

Write Protected

Write Protected

Write Protected

Write Protected

28

29

None

Return

None

None

None

Gnd

Gnd

Gnd

Not connected

29

30

None

Read Data

None

None

None

Read Data

Read Data

Read Data

Read Data

30

31

None

Return

None

None

None

Gnd

Gnd

Gnd

Not connected

31

32

None

Head Select ***

None

None

None

Side Select **

Side 1 Select

Side 1 Select

Side 1 Select

32

33

None

Return

None

None

None

Gnd

Gnd

Gnd

Not connected

33

34

None

Ready

None

None

None

Ready

Ready

Disk Change

Ready

34

* Normally not used

** Only for double sided drives

*** Only for NMS8245

PC drive for Sanyo Wavy 70FD2

Now, let’s see how we can adapt a normal PC drive on Sanyo Wavy 70FD2. This can be extended to all MSX typesIn Sanyo, pins 7, 9 and 11 are +5V. For others MSXes these pins are Gnd, there you must take +5V from the power supply.

What you will need:

  • One PC flat cable for 3.5″ drives;
  • One PC power connector for 3.5″ drives;
  • Some isolator adhesive tape;
  • This table;
  • Patience;
  • And, of course, a PC 3.5″ floppy drive or two, if you wish have A: and B: units.

For SANYO users ONLY:

  • Get the PC flat cable and isolate the pins 7, 9 and 11 the red wire is pin 1;
  • Get the PC flat cable and isolate pin 13;
  • Get the PC powerconnector and plug the pins 7, 9 and 11 to the red wire;
  • Get the PC powerconnector and plug the pin 13 to the black wire next to the red;
  • If you wish, cut off the other black and yellow wires from power connector. They won’t be useful

For turbo R users:

It is hard to find the right drive, because you need both a disk change signal and a ready signal, for example: a Teac drive with *lots* of jumpers.
You can fake either signal, but performance will suffer. Still better than a broken drive though. The disk change signal can be faked by returning “changed” at all times connect to gnd. This is correct, but it disables the caching flushed every I/O action. The ready signal can be faked by connecting it to a “disk inserted” sensor. If your drive does not have such a sensor, use the HD hole sensor, since MSX disks are DD and don’t have a hole there, thus pressing down the sensor. The drawback of this faking is that seeking from one track to the next becomes slower and more noisy. notes by Maarten ten Huurne.

For VG8235

This MSX computer has a diskrom only suited for a single sided drive. To make use of a doublesided drive, including the PC type, you need to replace the diskrom with the rom from a VG8245, see the manual how and where.
Also you need to add the side selection signal, not present at the internal drive A but available at the connector for the external drive B. Connect pin 32 of drive A to pin 32 of the external connector for drive B. Again, see the VG8235 service manual!

Notes by Toby

Pin 6 of the turbo R drive connector holds the ready signal. Ground this when a disk is inserted. Most drives have a suitable sensor. Make sure you check it goes to ground, not 5V when a disk is inserted. If so, connect the ready pin to this sensor. My drive had an optical sensor which went high on disk insert, so I had to place a small switch instead. It has worked fine for some time now. Check to see if pin 6 also holds the ready signal on your WSX. My guess is that it does…

I really don’t know if the WSX also has the ‘disk changed’ function the turbo R has. If it does it is most likely on pin 24 as well. If the WSX has it too, try either grounding it for a quick’n’dirty fix or ground it whenever there is NO disk inserted. If you need to place a switch like I did, make sure it has a dual throw ? so you can connect the ‘disk changed’ pin to the opposite side of the switch.

I think you’re not supposed to leave the pins ‘open’ at any time and are supposed to hook them up to a resistor and 5V+ or something, but I really don’t know the exact science behind it. I just left them hanging anyways; not how it’s supposed to be, but hey… Anyways, that’s how I solved the problem. Seemed to have worked just fine. The drive doesn’t work as neatly as the real Turbo-R drive did, but it does the trick and all software seems to work okay. Anyways, good luck..

For all users

  • See if your Floppy drive have some jumper. If yes, search for one RDY or Ready jumper and set it to Ready position different from its actual position. This is needed because PC doesn’t have a Ready function, which indicates that exists a disk on drive. If your drive doesn’t have jumpers, just connect the pin 34 onto any odd pin connected Gnd. This will always send a Ready signal to the computer even if drive is NOT ready.
  • The PC drive is always set to DS1: which is the B: drive. If the drive is started at boot but doesn’t work like A: drive, you will have to plug WIRE 10 on PIN 12 and WIRE 12 on PIN 10. This is not needed if you wish to use the drive as B:. Alternatively some PC drives have solder jumpers, default to DS1 but changeble to DS0.

That’s all!

Here are some things that could happen

  • The drive spinned up but the MSX does not boot the inserted disk. Solution: the drive was plugged in B: channel. Changing the pins 10 and 12 solves the problem. And thus, this is not a problem if you really want the PC drive as a B: unit!
  • The drive was started, the MSX tries to boot, but says that there is no disk on drive disk offline.
    Solution: Send Gnd trough pin 34. this can be done in the cable and is best that way: maybe someday you would want to plug this drive on a PC again, and a PC with Ready signal only works for read and only under Windows!
    Alternative: some PC drives Samsung, Teac allow to change the function of pin 34 from the default PC “Disk Changed” to the MSX default “READY”. Open the floppy drive and look at the printed circuit for solder jumpers or SMD resistors and strings like RDY.
  • HD disks doesn’t work. Solution: remember: you are using a HD PC drive!!! You must cover the HD hole in HD disks using a adhesive tape. Now a question: would be possible to MSX read a 1.44Mb disk? Maybe if we do an “upgrade” to DOS kernel…
  • If your MSX does not turn on, and if it doesn’t provide a power connector like Sanyo, is almost certain that the +5V are wired wrong in the data cable causing a short circuit. In this case, look careful at your drive connector to see what pin has +5V. I discover this by scanning my main board, then I saw a red cable coming from MSX power supply, and I just follow the path of that wire which is connected to pins 7, 9 and 11. Maybe you could also find it this way.