MSX Info pages

MSX Floppy drives

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 .

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.

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