NEC floppy troubles..

[ggn]

Hi all,

I purchased recently a NEC FD1231H floppy drive to replace the one that died on my STE. Although I have done this several times in the past, I have some problems with this.

I know that I have to change the jumper that has drive select 1 to drive select 0. I have even de-soldered and re-soldered zero resistance resistors on some floppies.

The problem is that I can't seem to locate these on this floppy

It has some jumpers on board, but these are just labeled J1, J2, etc.

I have e-mailed NEC about it but still haven't received a reply from them.

Anyone can help? I might be able to produce a photo of the floppy if it can help further.

George

[simbo]

Hi ggn

as you have only a few jumpers
take a note of them and start swapping


however if you cut the daft cable and header off the ataris board and replace it with a floppy header socket

any pc drive will work
that supports the format type {720K+}

then use a standard pc cable as per pc
{twisted cable to floppy other end to the main board}

this sometimes screws up the external drive

http://www.msc-ge.com/frame/prodsearch/ ... D/306.html


at this link your going to find the datasheet for the drive

good luck and may the force be with you


youll notice i used google search string note the use of ++ arithmetic functions to narrow the field

http://www.google.co.uk/search?hl=en&q= ... heet&meta=

NEC FD1231H ++ datasheet

also remember there are a few - models for this floppy

like NEC FD1231H-302

so check this out and use the exact one

in this case i think its just
does it have a front
is it white grey black etc etc models
and the electronics it uses are the same

but watchout for 2.88mb types
some series have these - model types also

sometimes like this link i notice it is a cut down datasheet
but notice the request info button
perhaps you can add an email address and ask for the full thing and not an extract

[ggn]

Hi Simbo,

-The thought of jumper (de/re)soldering came to me. Maybe I'll try it.

-Replace the floppy cable? I'm scared

-From the first link I Identified the floppy as FD1231H-305. Now what?

-I'll re-send some requests on NEC and see what happens.

Thanks

George

[simbo]

ye sorry for the dodge datasheet just ssems page ten is there

boho

i also placed a request with the american nec site to double up the chances of help

i think the best thing is to look for another lsi drive that uses a similar electronics

in ataris i have found only sony and teac drives as standards
but nec should work

ill have an hour and check around the ftp's seeif i can dig some data

if you look on the vezz site {files seems awl wonder what happened}

i also backedup a complete set of them so again ill look thru the projects see if i can find the data

sounds like a drive i have seen used before

dont worry and dont take no for an answer

if i dont get an answer from email i look for a telephone number and check timezones then phone

its very often mail boxes like there is stuffed with spam and etc so
you may never ever get even an answer from nec

keep looking and please post results so the valuble info can be added to the topic sticky

tia

[simbo]

http://www.nec.se/upload/I-notes/

found this link ill post others

similar drive




older drives

http://www.nec.se/templates/Page.asp?id=2278


i would send these guys an email also

[ijor]

-Replace the floppy cable? I'm scared

Then just make a short extension (and twisted) cable. IMHO this is the better solution, because you can use the same cable with any other PC drive.

[Greenious]

Another alternative is to use a multimeter or similar tool to find out where pin 12 & 14 of the contact meet up in a cluster that looks like jumpers.

Pin 14 is drive select 0 (the one that should be active)
Pin 12 is drive select 1 (active default on PC)

Pin 2 is density select. Might be necessary to look at this one aswell to enable HD/DD mode correctly.

[simbo]

sorry for my crap post but i am honestly not shure of floppy disks replacements with hd drives

never used this approch just used a 030 and be done with it

appart from this maybe kiss the floppy goodbye for ever
and use a smart card is overall the best approch
they are so cheep

you can get a 8mb card for as little as 50p {1euro}

i think someone should bridge the floppy to usb port
using a pic 16F672 or similar usb enabled chip
or bridge asci to smart direct is better
and a worthwhile tool instead of the middle ide

or direct connect it to the floppy controller

i kinda like the smart card idea its maybe just as hard to fit as hd/dd mod kit and trying to find info on floppys is sometimes hard...



http://www.techadvice.com/help/Products ... drives.asp

examples of dollar types for use in pc land
can be used via ide to usb adapter

soldering a 40 pin turnpin socket direct to the dma chip is enought
to get access without too much work in asci rear sockets land
and use the floppy via the hard disk instead rewriting the boot sequence

would be enought to boot the machine from hdd{smart} and if a smart floppy is inplace boot from this instead however still via asci instead of the floppy

still ill miss the tune my version of cubase plays as it loads up...

a new version of tos is needed or a patch

not so hard to make up using steem or similar


maybe link w2 is all you need instead of drive surgery
look at the schematic of the stfm or w300 w301 in ste

and its back to fiting a socket into the atari and getting rid of the straight cable

its actualy easy to do {not hard}
there is a full explination how to do this in the faq's in the stickys

again for the hd mod its just a matter of switching the atari floppy controller clock from 8 to 16mhz

{via the hd/dd select as usual with 74 series logic}

if you use the twisted cable inside you can cut the spare bit of
this way
1} no drive surgery
2} no screwed up external port
3} simplified hd disk mod

the only then remaining problem is the external drive
most external drive units contain a teac or sony crapo drive
replacing this also with a pc type 144/720k switchable
will yield a hd dd external one also
and maybe a jumper will need changed on it to change its ident
from a to b
and this can be done on the fly {power on } no need to power down for this change {provided you know what jumper it is
{usualy j1 or j2 but dont quote me}

with heinsight i dont even think this will need changed


i added a 'change internal floppy header for a socket' method
to the simbo faq's





as a final point about multimeters /dmm's

DONT use the continuity check to find pins
{beeeeep for a resistance under 20R}

as excessive current used for this test
that most meters will shunt thru the gear

could easily cook the lsi on the drive etc....

instead use the diode check range
{no beep but fully safe on delicate gates}

[stimpy]

The switching of those pins listed by Greenious should work if the drive doesn't have them.

I think a PIC can't act as a master for USB, I could be wrong though.

I've never had trouble getting a PC drive to work on ST's apart from many don't provide the jumpers. I usualy cut the tracks and switch the wires over. A PC floppy drive is worth nothing these days.

[simbo]

ye it should work ok however a permanant solution is far better
without touching the drives lsi interface
as this will also affect the external drive socket

i agree that a floppy disk /drive is worthless so why bother using it at all
and is redundant technologie that any magnet can wipe sticky fingers damage
and disk that crunch all you work up


ill stick to smart cards personaly

as for pic if you look at many free c compiler's

youll see most makers even mplab {microchip}
has drivers for mastering a bus

if this is a problem youll find any device MUST act also as a master

it matters not

there is no need of bus controller just interface to usb from dma
usb is in essance extended i2c

fdtd chips can also be used to interface to any mcu
then to the dma controller by passing the wd floppy controller
that wasnt designed for high density and gets hot and bothered at 16 mhz



and use the floppy slot as the card slot instead

a much better idea and more friendly to the pc these days

someone just needs to add a sensible project around it as a wrapper
draw up a circuit and make the code avalible

its ataris fault for not doing the header correctly in the first place

the main problem comes with the destruction {eventualy will happen} of the WD floppy controller it will take out the DMA controller also

and then you have a big problem

a nicer solution is direct bus access via the dma chip
cut off the WD controller and save the future grief finding parts

smart to be smart stupid is the floppy

smart is far more complient as images are fully avalible and can be used in hardware as well as steem and others
making it easier to use there image file software version's

that will be better debugged with time

[ggn]

-Replace the floppy cable? I'm scared

Then just make a short extension (and twisted) cable. IMHO this is the better solution, because you can use the same cable with any other PC drive.

How can I do that? I have some PC floppy twisted cables, can I do something to it? Is there something like an adaptor for daisy chaning the cable on my ST to this cable? Or do I have to make it myself (hotwiring 35 or so pins? )?

George

[ijor]

-Replace the floppy cable? I'm scared

Then just make a short extension (and twisted) cable. IMHO this is the better solution, because you can use the same cable with any other PC drive.

How can I do that? I have some PC floppy twisted cables, can I do something to it? Is there something like an adaptor for daisy chaning the cable on my ST to this cable? Or do I have to make it myself (hotwiring 35 or so pins? )?

Well, you can't use a PC cable directly, which would require at least a gender changer.

You don't have to make it yourself. Just have it done by somebody else.

[ggn]

I had a small idea for the "gender changer": I de-soldered the floppy conntector from an old (dead) floppy drive. Will this act as one and can I plug in two floppy cables at both ends (one is the st's and the other the floppy cable from the pc)???

George

[simbo]

yes

what you need to do is plug the two 'cables' together

but first study the two drives in an atari post
it works
two drives on a normal pc cable with NO jumper changed on floppy at all

you need to modify the cable and if you can be bothered turn the
st pcb out and add the link below

with ste
you only need add a link between pins 10 and 14
on the underside of the floppy header

then also modify the cable

all the details are here

http://www.atari-forum.com/viewtopic.ph ... 7&start=30


as a point for a general note

just about any drive will work with this method {later pc ones}

many suppliers sell for about 10-15 euros, a drive does hd and dd disks.

however i think this mod moves the goal posts for the nec drives you have


and i dont see further problems provided you follow the mod for ste

and put any jumpers on the drives you changed back where they were

[Lando_C]

Hey I just made the two-internal-drives-on-a-pc-cable mod.

If your original floppy cable is OK, then all you need is the genderchanger, and a standard PC floppy cable, and it *should* work, on an STE. You need the motor on signal for drive B, though, as Simbo says.

In the STF and -FM you need to do this:

(or cut at the header of the PC cable if you want your atari to be easy to restore to original), and wire up the signals correctly,


* cut cable 10 and wire it to pin 16 (together with cable 16)
wire pin 12 to pin 10 on the backside of the motherboard.
wire pin 14 to the external port's drive select B pin on the backside of the mobo (which one, 5 or 6 depende on your motherboard version)

you can wire on the front of the mobo, if you dont want to lift it out of the metal backing, but then you wire 14 to the appropriate bridge in the bridge bank (the row of 0-ohm resistors) near the floppy external port.)

[simbo]

hi
to add its an ste


no need of extra drive signal {ste has both of them at the floppy header}

just pins 10 - 14 underside of the pcb {floppy header}

cut 10 wire and move also to 16

i think this is cool at last we solved this problem

[ggn]

A small question before I do the actual mod: Is it ok to hotwire the pins for ste or is a pullup/pulldown resistor needed just in case?

(question coming from my brother who didn't allow me to do the mod because he was afraid I might even fry the ste!)

George

[simbo]

just to clarify to others


do this mod to a standard pc twist cable if you intend to use a gender changer instead of replacing the header on the pcb with a socket




snip wires 10 and 14 about 2 inches from the plug to the board {or gender changer adapter} end of the header

{ not the floppy ends }

wire 10 gets connected as well to wire 16 solder it on to it

wire 14 gets connected to the old wire 10 {plug end}

old wire 14 {plug end} dosnt get used



problem solved no pcb mod needed
{ste only .......... stf stfm still needs drive 1 signal
tapped from pin 5 or 6 of the external floppy socket as per other posts about dual drives on stf etc...}

[ggn]

Well, I just tried it and it didn't work

To be more precise, here's what I did (Note: I have an STE):

a) De-soldered a floppy connector from a dead drive and baptised it "gender changer" The one end has a socket (which the floppy cable was meant to be plugged) and the other has the pins that were originally soldered to the floppy's motherboard. Let's call the socketed side "A" and the other "B"

b) From side "A" I counted 5 wires from the upper left. That, from schematics I saw, appears to be pin 10. Then I went in side "B" and cut this pin. What remained from the pin would be stuck in the floppy cable that goes there.

c) Same thing again: went to side "A", loated pin 14 (7th wire from up left) and cut it on side "B"

d) Took 2 small pieces of wire

e) I soldered the first piece with what was left from pin 10 and pin 16 on side "B" (8th from the up left corner, always looking at side "A")

f) I soldered the second piece with what was left from pin 14 and pin 10 on side "B"

g) Connected everything. That is, I took the STE's floppy cable, connected to side "A" of the gender changer, took a PC twisted floppy cable, connected one end to side "B" and slid in the cut pins in the proper places, and the twisted side went to the floppy.

After giving power to the floppy I switched on. Nada The drive LED doesn't even blink.

Ummm, help?

I'll try to take some snapshots if my description above was confusing.

(Note, I have an old floppy that is wired up ok. When I connect this to the STE's floppy cable and give power, the head works as it should. So I assume that the cable is ok).

George

[simbo]

others seem to have no issues doing this

[ggn]

Hmm, judging by the schematic, I have a feeling I soldered the plug upside-down

What plug is being shown there? The male, or female?

Also, where is pin 1 located? Bottom right?

George
(hardware _is_ rocket science to me )

[simbo]

pin 1 is the bottom right of the picture with a 1 beside it

the order of the wires shown there are 2 4 6 8 10 12 ...

this view show's the socket on the st as if you had one inplace
{it is the correct pinout for a dil used for a 34 pin header also the top left of the socket show is pin 34}

the red wire on any drive cable is and should be pin 1

the cable goes red =1 then 2 3 4 5 6 7 8.... from the red wire to the other end

i hope you solve it would be nice to get a success post

dont worry its just a snag every job has them
be patient and soldier thru
download the picture can help and magnify in windows picture viewer
as i say